Copyright 1992 by the American Psychological Association, Inc. 0882-7974/92/S3.00
Psychology and Aging 1992. Vol. 7, No. 3, 367-375
Mental and Physical Health of Spouse Caregivers: The Role of Personality Karen Hooker, Deborah Monahan, Kim Shifren, and Cheryl Hutchinson
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
Syracuse University Although personal resources of caregivers, such as coping skills and social support, have been shown to be important in understanding caregiver stress and health outcomes, personality traits have not previously been considered. The purpose of this study was to examine the association between the personality traits of neuroticism and dispositional optimism and mental and physical health outcomes. It was predicted that personality would have direct effects, and indirect effects through perceived stress, on health outcomes. Participants were spouse caregivers of patients diagnosed with Alzheimer's disease. Results showed that neuroticism and optimism were significantly related to mental and physical health. Furthermore, neuroticism had significant direct effects on all of the health outcomes, and substantial indirect effects, through perceived stress, on mental health outcomes. Optimism showed stronger indirect than direct effects on all health outcomes. These findings demonstrate the importance of including personality of the caregiver in theoretical and empirical models of the caregiving process.
The process of giving care to a person with a dementing illness is universally viewed as highly stressful (e.g., Gatz, Bengtson, & Blum, 1990; George & Gwyther, 1986; Mace & Rabins, 1981; Zarit, Orr, & Zarit, 1985). Results from many studies (see Schulz, Visintainer, & Williamson, 1990, for a review) suggest that the strain of caregiving is responsible for deterioration in caregivers' mental health and possibly their physical health (e.g., Horowitz, 1985; Kiecolt-Glaser et al., 1987; Moritz, Kasl, & Berkman, 1989; Ory et al, 1985; Pruchno & Potashnik, 1989; Vitaliano, Maiuro, Ochs, & Russo, 1989). However, there are great individual differences in the ability of caregivers to cope with what would seem to be objectively similar situations (e.g., Haley, Levine, Brown, & Bartolucci, 1987). In fact, research indicates that there is no direct relationship between level of impairment in the care recipient and the caregiver's reported stress (e.g., George & Gwyther, 1986; Haley et al, 1987; Pagel, Becker, & Coppel, 1985; Zarit, Reever, & Bach-Peterson, 1980). Characteristics of the caregiver, such as coping skills (e.g, Haley et al, 1987; Pruchno & Resch, 1989; Stephens, Morris, Kinney, Ritchie, & Grotz, 1988) and social support (e.g, Clipp & George, 1990; Schulz & Williamson, 1991), seem to be more important than the care recipient's level of impairment in predicting caregiver burden and the health consequences of such perceived stress. From a cognitive phenomenological perspective (e.g, Lazarus & Folkman, 1984), variation in adaptation to what would seem to be objectively similar stresses suggests that people have different interpretations of, and reactions to, stressful situations (e.g, DeLongis, Folkman, & Lazarus, 1988). A person's reaction
to a stressor is thought to be influenced by subjective appraisal of the stressor. Personality has been hypothesized to affect the appraisal process. People assign meaning to a situation through an interactive, constructive process in which personality plays a key role. The process by which subjective appraisal of "the same" stressor results in different appraisals across individuals is not well specified. Studies of the relationships between personality and health are numerous in the personality literature (see Carson, 1989) and the behavioral medicine literature (see Rodin & Salovey, 1989). Although many theoretical and methodological issues remain to be resolved (see Krantz & Hedges, 1987), there is emerging consensus that certain personality characteristics can put one at risk for specific diseases (e.g, hostility has been shown to be predictive of coronary heart disease; Barefoot, Dahlstrom, & Williams, 1983) or disease in general (Barefoot et al, 1987; Friedman & Booth-Kewley, 1987). Research on personality characteristics that make an individual more vulnerable to disease implicate negative emotional states such as hostility and anger (Williams et al, 1988; see Taylor, 1990, for a review). Of the five broad dimensions, or traits, that seem to adequately represent the major domains of personality (Carson, 1989), neuroticism comes the closest to embodying these negative affective states. Increasingly, researchers are also emphasizing the role of positive emotional states in protecting against illness. Examples of personality characteristics shown to enhance health are hardiness (a composite of commitment, control, and challenge; Kobasa, Maddi, & Kahn, 1982) and optimism (e.g, Reker & Wong, 1985; Scheier & Carver, 1987). Scheier et al. (1989) found that dispositional optimism was related to coping efforts and actual physical recovery from coronary artery bypass surgery. It is especially interesting that optimism, a personality variable, predicted "hard" health outcomes, such as new Q-waves on a patient's electrocardiogram, because there is current controversy about the relationship of neuroticism to physical illness. Neuroticism itself is related to inflated symptom reports (e.g.
This research was supported by the All-University Gerontology Center and the Office of Research, Syracuse University. It was completed while the authors were supported by an award from the National Institute of Mental Health (R03 MH46637) to Karen Hooker. Correspondence concerning this article should be addressed to Karen Hooker, Department of Psychology, 430 Huntington Hall, Syracuse University, Syracuse, New York 13244.
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Costa & McCrae, 1985a, 1987; Watson & Pennebaker, 1989). Evidence suggests that neuroticism inflates correlations between stress as measured by life event checklists and self-report inventories of medical conditions (Schroeder & Costa, 1984; but see Maddi, Bartone, & Puccetti, 1987). Thus, Watson & Pennebaker (1989) argued that neuroticism should be considered a "nuisance variable" in health-related research. However, psychologists may want to pause before accepting such an argument. It may be that neuroticism does not have a direct effect on health, but that individuals high in neuroticism truly are more stressed (with the attendant negative health consequences that would be manifested over time) because they are more likely to appraise situations as threatening (cf. Ormel & Wohlfarth, 1991). Although personality of caregivers has not, to our knowledge, been systematically examined, results from existing caregiving studies suggest that personality is indeed a construct worthy of further study in relationship to caregiving. For example, in a study designed to examine caregiver burden, anxiety and hostility subscales of the Brief Symptom Inventory showed elevated levels among caregivers (Anthony-Bergstone, Zarit, & Gatz, 1988). In a study comparing caregivers to noncaregivers, scores on anger-in and anger-out were higher among the caregivers (Vitaliano et al., 1989). Gallagher, Wrabetz, Lovett, Del Maestro, & Rose (1989) found that anger was the most common negative affect among caregivers of Alzheimer's disease (AD) patients. Vitaliano, Russo, Young, Teri, and Maiuro (1991) presented an elegant model of caregiver burden emphasizing vulnerability and resources in which expressed emotion and anger (conceptionalized as vulnerabilities) were related to burden. Both hostility and anger have been linked to physical health outcomes (see Friedman & Booth-Kewley, 1987). Because caregiving may go on for years, damage from daily feelings of hostility and anger might accumulate, resulting in poor health. On the other hand, personality characteristics such as optimism may protect the caregiver from some of the negative consequences of stress. Because little is known about the relationships between personality, stress, and health outcomes among caregivers, the goals of this study were primarily exploratory. We examined the degree to which personality related to overall perceived stress (not caregiver strain per se) and health outcomes. In addition, consistent with a cognitive phenomenological approach (e.g., Lazarus & Folkman, 1984; Pearlin, Mullan, Semple, & Skaff, 1990), we hypothesized that personality characteristics would have indirect effects—through associations with perceived stress—as well as direct effects on mental and physical health outcomes. Thus, we predicted that individuals high in neuroticism or low in dispositional optimism will experience daily life events as more stressful and will have poorer mental and physical health outcomes than individuals who are low in neuroticism or high in dispositional optimism. In studying a group that previous research has shown to be under extreme stress, we are following a theoretical strategy that Baltes (1987) called "testing-the-limits" (p. 611). That is, if there are relationships between personality, stress, and health outcomes, they should be more easily observed in a group for which stress levels are relatively high. In sum, the purposes of this study were (a) to determine
whether the personality characteristics of neuroticism and optimism are associated with physical or mental health among spouse caregivers of dementia patients, and (b) to test the hypothesis that personality characteristics are related both directly, and indirectly through perceived stress, to mental and physical health.
Method Participants Participants for this study were 51 spouse caregivers (26 wives, 25 husbands) of persons who had a confirmed diagnosis of AD or a related dementia. Requirements for participation were that the caregiver and care recipient live in the same household, and that the caregiver consider himself or herself to be in the caregiving role fora minimum of one year. This was to ensure that caregivers had experienced stress associated with their role for some time. Caregivers were recruited from a variety of sources, including the Alzheimer's Disease Assistance Center associated with a medical center, support groups associated with the local chapter of the Alzheimer's Disease and Related Disorders Association (ADRDA), and a local paper targeted toward seniors. The caregivers who participated in the study had a mean age of 68.7 years (SD = 8.7) and were married an average of 43.5 years (SD = 10.3); 98% were White (one woman was Black), most (90.2%) were in their first marriage, and had living children (86.3%). The majority of the sample (55%) was retired, and only 10% were still working full time. The Hollingshead Four-Factor Index (Hollingshead, 1975) was used to determine socioeconomic status (SES). The possible range of scores on this measure is from a low of 8 to a high of 66, and participants had an average score of 44 (SD = 13). The sample was well educated, as the mean number of years of education was 13. They had been caregiving for an average of 4.6 years (SD = 2.7).
Measures Personality. NeuroticismwasoperationalizedbyscoresonFactorN (neuroticism) of the NEO Five Factor Index (NEO-FFI; Costa & McCrae, 1989), a short version of the NEO Personality Inventory (NEO-P1). We chose the short version over the longer version (60 items vs. 181 items) because of time constraints that we had to consider with an older sample of caregivers. Factor N on the NEO-PI contains the facets labeled anxiety, hostility, depression, self-consciousness, impulsiveness, and vulnerability. According to Costa and McCrae (1985b), individuals scoring highly on N can be characterized as "worrying, nervous, emotional, insecure, inadequate, and hypochondriacal" (p. 2), whereas low scorers can be characterized as "calm, relaxed, unemotional, and hardy, secure, and self-satisfied" (p. 2). Factor N on the NEO-FFI is a single index of 12 items that has been found to correlate highly with Factor N from the NEO-PI (r = .89), and, like the longer inventory, the NEO-FFI has been shown to have strong validity and high internal consistencies, and to be free of response set biases. Cronbach's alpha for Factor N in this study was .82, indicating good internal consistency. The second measure of personality was the Life Orientation Test (LOT), which is a measure of dispositional optimism (Scheier & Carver, 1985) with good internal consistency, test-retest reliability, and strong validity. Cronbach's alpha for the LOT in this study was .75. Perceived stress. Overall stress levels were indexed by the Perceived Stress Scale (PSS), a reliable and valid 14-rtem measure designed to be "sensitive to chronic stress deriving from ongoing life circumstances" (Cohen, Karmarck, & Mermelstein, 1983, p. 387). Sample items from this scale are "In the last month, how often have you felt that you were
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PERSONALITY AND CAREGIVING effectively coping with important changes in your life?" and "In the last month, how often have you been able to control the way you spend your time?" Response categories are never (4), almost never (3), sometimes (2), fairly often (1), and very often (0). Cronbach's alpha for the PSS in this study was .89. In accordance with recommendations by George and Gwyther (1986), we assessed stress appraisal with a measure that is not specific to the caregiving situation, so that our results may be compared with results with adults across a wide variety of stressful situations. In addition, it made sense theoretically to examine stress in general, because we were interested in understanding how global personality traits may directly and indirectly affect health. Health outcomes are probably due to overall stress levels, not stress related to a certain class of stressors. However, one would expect that stress related to caregiving would be captured in the measure of general stress. Indeed, the PSS correlated significantly and in the expected direction with variables that could be thought of as directly related to caregiving stress. One of these variables was a health item: "Has your physical health been affected by caring for your spouse?" Respondents answered "yes," "no," or "I don't know" (only two caregivers gave this response). This item correlated significantly, r(49) = -.48, p = .0004 (two-tailed), with the PSS. The other variable consisted of two items pertaining to appraisal of the caregiving situation. The item "In general, the stress of caring for my spouse is something that I view as challenging (stimulating, intriguing, a welcome test of my abilities)" correlated significantly, r(49) = -.42, p = .003 (two-tailed), with the PSS. The item "In general, the stress of caring for my spouse is something that I view as threatening (potentially dangerous either physically or psychologically)" also correlated significantly, r(49) = .34, p = .01 (two-tailed), with the PSS. Thus, the PSS correlated with appraisals of caregiving stress, but was meant to encompass more broadly all of caregivers' current stress. Previous research has shown that there is no relationship between caregivers' stress and functional impairment of the care recipient (e.g., Drinka, Smith, & Drinka, 1987; George & Gwyther, 1986; Haley et al., 1987; Zarit et al., 1980). However, we collected information on the caregivers' reports of their spouses' ability to perform basic (e.g., eating, toileting) and instrumental (e.g., shopping, handling finances) activities of daily living (ADLs) and the caregivers' appraisal of how much help they were providing for each ADL in order to assess the relationship between caregivers' perceived stress and functional impairment in their spouses among individuals in our sample. Mental health. One of the measures of mental health was the Center for Epidemiologic Studies Depression Index (CES-D; Radloff, 1977), a 20-item scale used to assess the overall level of depression experienced in the past week. It is suitable for use in general populations and has strong psychometric properties (Shaw, Vallis, & McCabe, 1985). This measure has been used with older adults (e.g., Himmelfarb & Murrell, 1983) as well as spouse caregivers (e.g., Pruchno & Resch, 1989), and found to have excellent reliability and validity. Possible scores range from 0 to 60, with higher scores indicating greater depressive symptomatology. In this study, Cronbach's alpha for the CES-D was .89. The 10-item Bradburn Affect Balance Scale (Bradburn, 1969) was another indicator of mental health and includes both positive affect and negative affect subscales. Cronbach's alpha for positive affect in this study was .65, and for negative affect it was .61. Following Bradburn, a single score, labeled affect balance, was derived by subtracting negative affect scores from positive affect scores. To avoid negative scores, a constant of 5 is added to each score. Thus affect balance scores can range from 0 to 10, with higher scores representing higher current levels of psychological well-being. Physical health. We used three measures of physical health in this study. One measure was the Current Health Subscale of the Health Perceptions Questionnaire (HPQ) used in the Rand Health Insurance Study (Davies & Ware, 1981). This subscale has good psychometric
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properties and was designed to provide discrimination at the less dysfunctional end of the illness continuum. This nine-item scale is scored so that higher scores indicate better health. An example of an item from this scale is "According to the doctors I've seen, my health is now excellent." Responses are definitely true (5), mostly true (4), don't know (3), mostly false (2), and definitely false (1). Cronbach's alpha for the HPQ subscale in this study was .94. Another measure of physical health was an index created from five items commonly used in health-related research. The items were (a) "In general, would you say your health is excellent, good, fair, or poor?" with responses being excellent (4), good (3), fair (2), or poor (1); (b) "During the past three months how much pain have you had?" with responses being a great deal of pain (1), some pain (2), a little pain (3), or no pain (4); (c) "During the past three months, how much has your health worried or concerned you?" with responses being a great deal (1), somewhat (2), a little (3), or not at all (4); (d) "Do your health problems stand in the way of your doing the things you want?" with responses being not at all (3), a little (2), or a great deal (1); and (e) "Would you say that your health is better, about the same, or not as good as most people your age?" with responses being better (3), same (2), or not as good (1). Responses on all five items were summed to form an index labeled health index, and Cronbach's alpha for this index was .77. These types of questions have been found to be predictive of morbidity and mortality (e.g., Idler & Kasl, 1991; Kaplan & Camacho, 1983). The third measure of physical health wasoneof thesubindicesof the Multilevel Assessment Instrument (MAI; Lawton, Moss, Fulcomer, & Kleban, 1982) and consisted of a checklist of chronic health conditions diagnosed by a doctor (e.g., diabetes, hypertension, heart trouble, and arthritis). Respondents answered "yes" or "no" to 20 chronic conditions listed, and had the opportunity to report any additional conditions that did not appear on the list. The MAI was designed for use with older samples and the validity and reliability of each of its domains and subindices is well documented (Lawton et al., 1982).
Procedure Potential participants were recruited through the various channels described above. If interested in finding out more about our study, they either returned a preaddressed, stamped postcard (if recruited by letter through the Alzheimer's Disease Assistance Center), or they called and left a message on our answering machine (if recruited through the support groups or newspaper advertisements). A member of the research team then called the potential participant and, after briefly describing the study, asked the following questions: (a) Does your spouse have dementia (memory loss)? (b) Has a diagnosis been made? (c) What is the diagnosis? and (d) How long have you been a caregiver? If the caregiver met the requirements for participation and agreed to participate in the study, an interview time was scheduled. Most of the care recipients had a confirmed diagnosis of AD. Only two had other types of dementing illnesses (one had Parkinson's disease, one had encephalitis). Caregivers had the opportunity to be interviewed in their homes (most chose this option), at the university (three participants preferred this option), or at some other public place (e.g., two participants preferred to meet in restaurants). Interviewers were highly trained research assistants (graduate students in clinical and developmental psychology, social work, and upper level undergraduate psychology students), all of whom were women, and the interviews lasted approximately one hour. Participants were paid $10 for their time. To limit the length of the interviews the Bradburn Affect Balance Scale and HPQ (along with other measures not relevant for this study) were left for the caregivers to complete on their own time. The interviewer gave instructions on how to complete the measures (instructions were
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HOOKER, MONAHAN, SHIFREN, AND HUTCHINSON
also printed on the questionnaires), asked that the caregiver try to complete them sometime within the next week, and left a preaddressed stamped envelope for them to mail back. If measures were not received by approximately 10 days after the interview, a follow-up phone call was made to remind caregivers to complete the measures. Compliance with this mail-back procedure was excellent, as only one caregiver (who was subsequently hospitalized) failed to return the measures.
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
Results Previous literature has shown that there is little relation between caregiver burden or stress and functional limitations in the impaired patient. We examined these relationships in our data by correlating scores on the basic ADLs with PSS (r = .00, ns) and instrumental ADLs with PSS (r = .05, ns). In addition, caregivers' appraisals of the amount of help they were providing with basic ADLs and instrumental ADLs were unrelated to scores on the PSS, correlations being r = —.08, ns, and r = .09, ns, respectively. Thus, functional limitations in the impaired spouse and the amount of help provided were not related to stress experienced by the caregiver. To determine whether there were relationships between personality traits and mental and physical health, we examined bivariate correlations between all of the theoretically relevant variables. However, we first performed an analysis to check on the omnibus null hypothesis that all possible population correlations were zero among this set of eight variables. This analysis is particularly important to conduct in exploratory studies in which sample size is relatively small and the number of variables is large (Cohen & Cohen, 1983) to avoid capitalizing on chance. The null hypothesis was rejected, x2(28, N = 51) = 483.8, p < .0001. Thus, individual correlation coefficients can be examined for significance (this test is analogous to using an overall F test to protect against Type I error before examining pairwise comparisons in an analysis of variance design). As shown in Table 1, neuroticism is significantly correlated, in the theoretically expected direction, with perceived stress and all of the mental and physical health variables. Those who have higher neuroticism scores rate themselves as more stressed
and as less physically healthy, have more depressive symptomatology and lower psychological well-being, and report having more chronic health conditions diagnosed by a doctor. Although not relevant for this study, the NEO-FFI factor Extraversion was significantly correlated with CES-D (r = -.37, p < .01), HPQ (r= .31, p < .05), health index (r = .37, p < .01), and number of chronic conditions (r = — .37, p < .01). The NEO-FFI factor Conscientiousness was negatively correlated with number of chronic conditions (r = -.35, p < .01). The NEO-FFI factors of Openness to Experience and Agreeableness were not significantly correlated with any of the mental or physical health measures. Optimism is significantly correlated, in the theoretically expected direction, with perceived stress and the mental health variables, but not with the physical health variables. Those who score highly on a scale of optimism rate themselves as less stressed, have fewer symptoms of depression, and have higher psychological well-being. To test the hypothesis that personality would be related to health outcomes directly, and indirectly through the effect of personality on perceived stress, we conducted path analyses. Figure 1 shows a diagram of the conceptual model being tested. In this study, all of the variables are measured (i.e., there are no latent variables). Therefore, as stated by Loehlin (1987): "So long as all variables are measured one can proceed to solve for the causal paths in a path diagram as beta weights in a series of multiple regression analyses" (p. 14). Cohen and Cohen (1983) described how to obtain partitioning of effects using hierarchical regression analyses. The regression coefficient when the variable first enters the hierarchy is its total effect. The regression coefficient in the final equation is, as always, its direct effect. The difference between the total and direct effects is the (total) indirect effect. . . . The indirect effect can be further partitioned in a hierarchical analysis by determining the change in each coefficient as a new variable is added to the equation. (Cohen & Cohen, 1983, pp. 360-361) Indirect effects can also be calculated as the product of paths. In this study the indirect effects of personality on health can be calculated by multiplying the path coefficient from personality
Table 1 Correlations Between Personality, Perceived Stress, and Mental and Physical Health Measure 1. Neuroticism (NEO-FFI) 2. Optimism (LOT) 3. Perceived stress (PSS) 4. CES-D 5. Bradburn affect balance 6. Current health (HPQ) 7. Health index 8. Number of diagnosed chronic conditions
1 — -.57**** .65**** -.50** — .75**** -.58*** .86**** — -.67**** .37* -.60**** -.57**** -.36" -.39** .15 -.43*** -.47*** -.47*** -.54**** .26
.44***
-.17
.29*
.43**
— .50*** — .35** .71****
—
-.35** -.52*** -.49*** —
Note. Ns ranged from 49 to 51. High scores represent more of the construct represented (e.g., high scores on the CES-D refer to greater depressive symptomatology). NEO-FFI = NEO Five Factor Index (Costa & McCrae, 1989); LOT = Life Orientation Test (Scheier & Carver, 1985); PSS = Perceived Stress Scale (Cohen, Karmarck, & Mermelstein, 1983); CES-D « Center for Epidemiologic Studies Depression Index (Radloff, 1977); HPQ = Health Perceptions Questionnaire (Davies & Ware, 1981). * p < .05 (two-tailed) ** p < .01 (two-tailed) *** p < .001 (two-tailed) **** p < .0001 (two-tailed)
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PERSONALITY AND CAREGIVING PERSONALITY,
MEOTAL HEALTH OR
PHYSICAL HEALTH
PERCEIVED STRESS
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Figure 1. Path model of the relations among personality, perceived stress, and mental or physical health. to stress (beta- 2 in Figure 1) with the path coefficient from stress to health (beta- 3 in Figure 1). Thus, personality variables and perceived stress were regressed on the outcome variables in two series of analyses. In the first series, five analyses were run in which each outcome variable was regressed on neuroticism and perceived stress in order to calculate direct and indirect effects. In the second series, the same analyses were conducted using optimism, rather than neuroticism, in the regressions. The direct and indirect path coefficients for the effect of personality on health outcomes are shown in Table 2. The total effects are, of course, represented in the correlations in Table 1.
cal health outcomes. For the mental health outcomes there were significant direct effects of perceived stress, and thus the indirect effect of neuroticism on mental health through its association with perceived stress was also quite strong. In fact, approximately one half of the total effects of neuroticism on mental health outcomes in the sample were due to indirect effects. In contrast, there were no significant direct effects of perceived stress on physical health outcomes. That is, there were no unique contributions due to perceived stress once neuroticism was partialed out of the equations. Thus, the indirect effects of neuroticism on physical health through perceived stress were also comparatively small. The adjusted percentage of variance explained in each of the five regressions ranged from 16% (for number of chronic conditions) to 79% (for CES-D scores). Neuroticism was significantly related to all of the health outcomes, independently of perceived stress. In addition, there were substantial indirect effects of neuroticism on mental health because of the association of neuroticism with perceived stress. Thus, in addition to the negative association of neuroticism alone on reported health outcomes, individuals who score highly on a neuroticism scale are more likely to perceive themselves as currently being under more stress, which in turn is associated with poor ratings of mental health.
Neuroticism
Optimism
As shown by the path coefficients in Table 2, there is a significant direct effect of neuroticism on all of the mental and physi-
In contrast with the results with neuroticism, the only significant direct effect of optimism on any of the outcomes was in the
Table 2 Path Coefficients for the Analysis of Personality, Perceived Stress, and Mental and Physical Health
Personality scale
Personality to health: 0,
Personality to perceived stress: /32
Perceived stress to health: 0,
Indirect path*— Personality to health through perceived stress: 02 x /33
Adjusted overall R2
Mental Health CES-D Neuroticism Optimism Affect balance Neuroticism Optimism
.32*** -.20*
.65*** -.50***
.65*** .76***
.42 -.38
.79*** .76***
-.32* .09
.65*** -.50***
-.40** -.56***
-.26 .28
.39*** .34***
Physical Health HPQ Neuroticism Optimism Health index Neuroticism Optimism Number of chronic conditions Neuroticism Optimism
-.34* -.04
.65*** -.50***
-.14 -.38*
-.09 .19
.17** .10*
-.41** .04
.65*** -.50***
-.20 -.45**
-.13 .23
.29*** .19**
.43** -.04
.65*** -.50***
.01 .28
.01 -.14
.16** .05
Note. CES-D = Center for Epidemiological Studies Depression Index (Rudloff, 1977); HPQ = Health Perceptions Questionnaire. * Significance levels are not reported for indirect paths (Cohen & Cohen, 1983). * p
Psychology and Aging 1992. Vol. 7, No. 3, 367-375
Mental and Physical Health of Spouse Caregivers: The Role of Personality Karen Hooker, Deborah Monahan, Kim Shifren, and Cheryl Hutchinson
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
Syracuse University Although personal resources of caregivers, such as coping skills and social support, have been shown to be important in understanding caregiver stress and health outcomes, personality traits have not previously been considered. The purpose of this study was to examine the association between the personality traits of neuroticism and dispositional optimism and mental and physical health outcomes. It was predicted that personality would have direct effects, and indirect effects through perceived stress, on health outcomes. Participants were spouse caregivers of patients diagnosed with Alzheimer's disease. Results showed that neuroticism and optimism were significantly related to mental and physical health. Furthermore, neuroticism had significant direct effects on all of the health outcomes, and substantial indirect effects, through perceived stress, on mental health outcomes. Optimism showed stronger indirect than direct effects on all health outcomes. These findings demonstrate the importance of including personality of the caregiver in theoretical and empirical models of the caregiving process.
The process of giving care to a person with a dementing illness is universally viewed as highly stressful (e.g., Gatz, Bengtson, & Blum, 1990; George & Gwyther, 1986; Mace & Rabins, 1981; Zarit, Orr, & Zarit, 1985). Results from many studies (see Schulz, Visintainer, & Williamson, 1990, for a review) suggest that the strain of caregiving is responsible for deterioration in caregivers' mental health and possibly their physical health (e.g., Horowitz, 1985; Kiecolt-Glaser et al., 1987; Moritz, Kasl, & Berkman, 1989; Ory et al, 1985; Pruchno & Potashnik, 1989; Vitaliano, Maiuro, Ochs, & Russo, 1989). However, there are great individual differences in the ability of caregivers to cope with what would seem to be objectively similar situations (e.g., Haley, Levine, Brown, & Bartolucci, 1987). In fact, research indicates that there is no direct relationship between level of impairment in the care recipient and the caregiver's reported stress (e.g., George & Gwyther, 1986; Haley et al, 1987; Pagel, Becker, & Coppel, 1985; Zarit, Reever, & Bach-Peterson, 1980). Characteristics of the caregiver, such as coping skills (e.g, Haley et al, 1987; Pruchno & Resch, 1989; Stephens, Morris, Kinney, Ritchie, & Grotz, 1988) and social support (e.g, Clipp & George, 1990; Schulz & Williamson, 1991), seem to be more important than the care recipient's level of impairment in predicting caregiver burden and the health consequences of such perceived stress. From a cognitive phenomenological perspective (e.g, Lazarus & Folkman, 1984), variation in adaptation to what would seem to be objectively similar stresses suggests that people have different interpretations of, and reactions to, stressful situations (e.g, DeLongis, Folkman, & Lazarus, 1988). A person's reaction
to a stressor is thought to be influenced by subjective appraisal of the stressor. Personality has been hypothesized to affect the appraisal process. People assign meaning to a situation through an interactive, constructive process in which personality plays a key role. The process by which subjective appraisal of "the same" stressor results in different appraisals across individuals is not well specified. Studies of the relationships between personality and health are numerous in the personality literature (see Carson, 1989) and the behavioral medicine literature (see Rodin & Salovey, 1989). Although many theoretical and methodological issues remain to be resolved (see Krantz & Hedges, 1987), there is emerging consensus that certain personality characteristics can put one at risk for specific diseases (e.g, hostility has been shown to be predictive of coronary heart disease; Barefoot, Dahlstrom, & Williams, 1983) or disease in general (Barefoot et al, 1987; Friedman & Booth-Kewley, 1987). Research on personality characteristics that make an individual more vulnerable to disease implicate negative emotional states such as hostility and anger (Williams et al, 1988; see Taylor, 1990, for a review). Of the five broad dimensions, or traits, that seem to adequately represent the major domains of personality (Carson, 1989), neuroticism comes the closest to embodying these negative affective states. Increasingly, researchers are also emphasizing the role of positive emotional states in protecting against illness. Examples of personality characteristics shown to enhance health are hardiness (a composite of commitment, control, and challenge; Kobasa, Maddi, & Kahn, 1982) and optimism (e.g, Reker & Wong, 1985; Scheier & Carver, 1987). Scheier et al. (1989) found that dispositional optimism was related to coping efforts and actual physical recovery from coronary artery bypass surgery. It is especially interesting that optimism, a personality variable, predicted "hard" health outcomes, such as new Q-waves on a patient's electrocardiogram, because there is current controversy about the relationship of neuroticism to physical illness. Neuroticism itself is related to inflated symptom reports (e.g.
This research was supported by the All-University Gerontology Center and the Office of Research, Syracuse University. It was completed while the authors were supported by an award from the National Institute of Mental Health (R03 MH46637) to Karen Hooker. Correspondence concerning this article should be addressed to Karen Hooker, Department of Psychology, 430 Huntington Hall, Syracuse University, Syracuse, New York 13244.
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Costa & McCrae, 1985a, 1987; Watson & Pennebaker, 1989). Evidence suggests that neuroticism inflates correlations between stress as measured by life event checklists and self-report inventories of medical conditions (Schroeder & Costa, 1984; but see Maddi, Bartone, & Puccetti, 1987). Thus, Watson & Pennebaker (1989) argued that neuroticism should be considered a "nuisance variable" in health-related research. However, psychologists may want to pause before accepting such an argument. It may be that neuroticism does not have a direct effect on health, but that individuals high in neuroticism truly are more stressed (with the attendant negative health consequences that would be manifested over time) because they are more likely to appraise situations as threatening (cf. Ormel & Wohlfarth, 1991). Although personality of caregivers has not, to our knowledge, been systematically examined, results from existing caregiving studies suggest that personality is indeed a construct worthy of further study in relationship to caregiving. For example, in a study designed to examine caregiver burden, anxiety and hostility subscales of the Brief Symptom Inventory showed elevated levels among caregivers (Anthony-Bergstone, Zarit, & Gatz, 1988). In a study comparing caregivers to noncaregivers, scores on anger-in and anger-out were higher among the caregivers (Vitaliano et al., 1989). Gallagher, Wrabetz, Lovett, Del Maestro, & Rose (1989) found that anger was the most common negative affect among caregivers of Alzheimer's disease (AD) patients. Vitaliano, Russo, Young, Teri, and Maiuro (1991) presented an elegant model of caregiver burden emphasizing vulnerability and resources in which expressed emotion and anger (conceptionalized as vulnerabilities) were related to burden. Both hostility and anger have been linked to physical health outcomes (see Friedman & Booth-Kewley, 1987). Because caregiving may go on for years, damage from daily feelings of hostility and anger might accumulate, resulting in poor health. On the other hand, personality characteristics such as optimism may protect the caregiver from some of the negative consequences of stress. Because little is known about the relationships between personality, stress, and health outcomes among caregivers, the goals of this study were primarily exploratory. We examined the degree to which personality related to overall perceived stress (not caregiver strain per se) and health outcomes. In addition, consistent with a cognitive phenomenological approach (e.g., Lazarus & Folkman, 1984; Pearlin, Mullan, Semple, & Skaff, 1990), we hypothesized that personality characteristics would have indirect effects—through associations with perceived stress—as well as direct effects on mental and physical health outcomes. Thus, we predicted that individuals high in neuroticism or low in dispositional optimism will experience daily life events as more stressful and will have poorer mental and physical health outcomes than individuals who are low in neuroticism or high in dispositional optimism. In studying a group that previous research has shown to be under extreme stress, we are following a theoretical strategy that Baltes (1987) called "testing-the-limits" (p. 611). That is, if there are relationships between personality, stress, and health outcomes, they should be more easily observed in a group for which stress levels are relatively high. In sum, the purposes of this study were (a) to determine
whether the personality characteristics of neuroticism and optimism are associated with physical or mental health among spouse caregivers of dementia patients, and (b) to test the hypothesis that personality characteristics are related both directly, and indirectly through perceived stress, to mental and physical health.
Method Participants Participants for this study were 51 spouse caregivers (26 wives, 25 husbands) of persons who had a confirmed diagnosis of AD or a related dementia. Requirements for participation were that the caregiver and care recipient live in the same household, and that the caregiver consider himself or herself to be in the caregiving role fora minimum of one year. This was to ensure that caregivers had experienced stress associated with their role for some time. Caregivers were recruited from a variety of sources, including the Alzheimer's Disease Assistance Center associated with a medical center, support groups associated with the local chapter of the Alzheimer's Disease and Related Disorders Association (ADRDA), and a local paper targeted toward seniors. The caregivers who participated in the study had a mean age of 68.7 years (SD = 8.7) and were married an average of 43.5 years (SD = 10.3); 98% were White (one woman was Black), most (90.2%) were in their first marriage, and had living children (86.3%). The majority of the sample (55%) was retired, and only 10% were still working full time. The Hollingshead Four-Factor Index (Hollingshead, 1975) was used to determine socioeconomic status (SES). The possible range of scores on this measure is from a low of 8 to a high of 66, and participants had an average score of 44 (SD = 13). The sample was well educated, as the mean number of years of education was 13. They had been caregiving for an average of 4.6 years (SD = 2.7).
Measures Personality. NeuroticismwasoperationalizedbyscoresonFactorN (neuroticism) of the NEO Five Factor Index (NEO-FFI; Costa & McCrae, 1989), a short version of the NEO Personality Inventory (NEO-P1). We chose the short version over the longer version (60 items vs. 181 items) because of time constraints that we had to consider with an older sample of caregivers. Factor N on the NEO-PI contains the facets labeled anxiety, hostility, depression, self-consciousness, impulsiveness, and vulnerability. According to Costa and McCrae (1985b), individuals scoring highly on N can be characterized as "worrying, nervous, emotional, insecure, inadequate, and hypochondriacal" (p. 2), whereas low scorers can be characterized as "calm, relaxed, unemotional, and hardy, secure, and self-satisfied" (p. 2). Factor N on the NEO-FFI is a single index of 12 items that has been found to correlate highly with Factor N from the NEO-PI (r = .89), and, like the longer inventory, the NEO-FFI has been shown to have strong validity and high internal consistencies, and to be free of response set biases. Cronbach's alpha for Factor N in this study was .82, indicating good internal consistency. The second measure of personality was the Life Orientation Test (LOT), which is a measure of dispositional optimism (Scheier & Carver, 1985) with good internal consistency, test-retest reliability, and strong validity. Cronbach's alpha for the LOT in this study was .75. Perceived stress. Overall stress levels were indexed by the Perceived Stress Scale (PSS), a reliable and valid 14-rtem measure designed to be "sensitive to chronic stress deriving from ongoing life circumstances" (Cohen, Karmarck, & Mermelstein, 1983, p. 387). Sample items from this scale are "In the last month, how often have you felt that you were
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PERSONALITY AND CAREGIVING effectively coping with important changes in your life?" and "In the last month, how often have you been able to control the way you spend your time?" Response categories are never (4), almost never (3), sometimes (2), fairly often (1), and very often (0). Cronbach's alpha for the PSS in this study was .89. In accordance with recommendations by George and Gwyther (1986), we assessed stress appraisal with a measure that is not specific to the caregiving situation, so that our results may be compared with results with adults across a wide variety of stressful situations. In addition, it made sense theoretically to examine stress in general, because we were interested in understanding how global personality traits may directly and indirectly affect health. Health outcomes are probably due to overall stress levels, not stress related to a certain class of stressors. However, one would expect that stress related to caregiving would be captured in the measure of general stress. Indeed, the PSS correlated significantly and in the expected direction with variables that could be thought of as directly related to caregiving stress. One of these variables was a health item: "Has your physical health been affected by caring for your spouse?" Respondents answered "yes," "no," or "I don't know" (only two caregivers gave this response). This item correlated significantly, r(49) = -.48, p = .0004 (two-tailed), with the PSS. The other variable consisted of two items pertaining to appraisal of the caregiving situation. The item "In general, the stress of caring for my spouse is something that I view as challenging (stimulating, intriguing, a welcome test of my abilities)" correlated significantly, r(49) = -.42, p = .003 (two-tailed), with the PSS. The item "In general, the stress of caring for my spouse is something that I view as threatening (potentially dangerous either physically or psychologically)" also correlated significantly, r(49) = .34, p = .01 (two-tailed), with the PSS. Thus, the PSS correlated with appraisals of caregiving stress, but was meant to encompass more broadly all of caregivers' current stress. Previous research has shown that there is no relationship between caregivers' stress and functional impairment of the care recipient (e.g., Drinka, Smith, & Drinka, 1987; George & Gwyther, 1986; Haley et al., 1987; Zarit et al., 1980). However, we collected information on the caregivers' reports of their spouses' ability to perform basic (e.g., eating, toileting) and instrumental (e.g., shopping, handling finances) activities of daily living (ADLs) and the caregivers' appraisal of how much help they were providing for each ADL in order to assess the relationship between caregivers' perceived stress and functional impairment in their spouses among individuals in our sample. Mental health. One of the measures of mental health was the Center for Epidemiologic Studies Depression Index (CES-D; Radloff, 1977), a 20-item scale used to assess the overall level of depression experienced in the past week. It is suitable for use in general populations and has strong psychometric properties (Shaw, Vallis, & McCabe, 1985). This measure has been used with older adults (e.g., Himmelfarb & Murrell, 1983) as well as spouse caregivers (e.g., Pruchno & Resch, 1989), and found to have excellent reliability and validity. Possible scores range from 0 to 60, with higher scores indicating greater depressive symptomatology. In this study, Cronbach's alpha for the CES-D was .89. The 10-item Bradburn Affect Balance Scale (Bradburn, 1969) was another indicator of mental health and includes both positive affect and negative affect subscales. Cronbach's alpha for positive affect in this study was .65, and for negative affect it was .61. Following Bradburn, a single score, labeled affect balance, was derived by subtracting negative affect scores from positive affect scores. To avoid negative scores, a constant of 5 is added to each score. Thus affect balance scores can range from 0 to 10, with higher scores representing higher current levels of psychological well-being. Physical health. We used three measures of physical health in this study. One measure was the Current Health Subscale of the Health Perceptions Questionnaire (HPQ) used in the Rand Health Insurance Study (Davies & Ware, 1981). This subscale has good psychometric
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properties and was designed to provide discrimination at the less dysfunctional end of the illness continuum. This nine-item scale is scored so that higher scores indicate better health. An example of an item from this scale is "According to the doctors I've seen, my health is now excellent." Responses are definitely true (5), mostly true (4), don't know (3), mostly false (2), and definitely false (1). Cronbach's alpha for the HPQ subscale in this study was .94. Another measure of physical health was an index created from five items commonly used in health-related research. The items were (a) "In general, would you say your health is excellent, good, fair, or poor?" with responses being excellent (4), good (3), fair (2), or poor (1); (b) "During the past three months how much pain have you had?" with responses being a great deal of pain (1), some pain (2), a little pain (3), or no pain (4); (c) "During the past three months, how much has your health worried or concerned you?" with responses being a great deal (1), somewhat (2), a little (3), or not at all (4); (d) "Do your health problems stand in the way of your doing the things you want?" with responses being not at all (3), a little (2), or a great deal (1); and (e) "Would you say that your health is better, about the same, or not as good as most people your age?" with responses being better (3), same (2), or not as good (1). Responses on all five items were summed to form an index labeled health index, and Cronbach's alpha for this index was .77. These types of questions have been found to be predictive of morbidity and mortality (e.g., Idler & Kasl, 1991; Kaplan & Camacho, 1983). The third measure of physical health wasoneof thesubindicesof the Multilevel Assessment Instrument (MAI; Lawton, Moss, Fulcomer, & Kleban, 1982) and consisted of a checklist of chronic health conditions diagnosed by a doctor (e.g., diabetes, hypertension, heart trouble, and arthritis). Respondents answered "yes" or "no" to 20 chronic conditions listed, and had the opportunity to report any additional conditions that did not appear on the list. The MAI was designed for use with older samples and the validity and reliability of each of its domains and subindices is well documented (Lawton et al., 1982).
Procedure Potential participants were recruited through the various channels described above. If interested in finding out more about our study, they either returned a preaddressed, stamped postcard (if recruited by letter through the Alzheimer's Disease Assistance Center), or they called and left a message on our answering machine (if recruited through the support groups or newspaper advertisements). A member of the research team then called the potential participant and, after briefly describing the study, asked the following questions: (a) Does your spouse have dementia (memory loss)? (b) Has a diagnosis been made? (c) What is the diagnosis? and (d) How long have you been a caregiver? If the caregiver met the requirements for participation and agreed to participate in the study, an interview time was scheduled. Most of the care recipients had a confirmed diagnosis of AD. Only two had other types of dementing illnesses (one had Parkinson's disease, one had encephalitis). Caregivers had the opportunity to be interviewed in their homes (most chose this option), at the university (three participants preferred this option), or at some other public place (e.g., two participants preferred to meet in restaurants). Interviewers were highly trained research assistants (graduate students in clinical and developmental psychology, social work, and upper level undergraduate psychology students), all of whom were women, and the interviews lasted approximately one hour. Participants were paid $10 for their time. To limit the length of the interviews the Bradburn Affect Balance Scale and HPQ (along with other measures not relevant for this study) were left for the caregivers to complete on their own time. The interviewer gave instructions on how to complete the measures (instructions were
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HOOKER, MONAHAN, SHIFREN, AND HUTCHINSON
also printed on the questionnaires), asked that the caregiver try to complete them sometime within the next week, and left a preaddressed stamped envelope for them to mail back. If measures were not received by approximately 10 days after the interview, a follow-up phone call was made to remind caregivers to complete the measures. Compliance with this mail-back procedure was excellent, as only one caregiver (who was subsequently hospitalized) failed to return the measures.
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Results Previous literature has shown that there is little relation between caregiver burden or stress and functional limitations in the impaired patient. We examined these relationships in our data by correlating scores on the basic ADLs with PSS (r = .00, ns) and instrumental ADLs with PSS (r = .05, ns). In addition, caregivers' appraisals of the amount of help they were providing with basic ADLs and instrumental ADLs were unrelated to scores on the PSS, correlations being r = —.08, ns, and r = .09, ns, respectively. Thus, functional limitations in the impaired spouse and the amount of help provided were not related to stress experienced by the caregiver. To determine whether there were relationships between personality traits and mental and physical health, we examined bivariate correlations between all of the theoretically relevant variables. However, we first performed an analysis to check on the omnibus null hypothesis that all possible population correlations were zero among this set of eight variables. This analysis is particularly important to conduct in exploratory studies in which sample size is relatively small and the number of variables is large (Cohen & Cohen, 1983) to avoid capitalizing on chance. The null hypothesis was rejected, x2(28, N = 51) = 483.8, p < .0001. Thus, individual correlation coefficients can be examined for significance (this test is analogous to using an overall F test to protect against Type I error before examining pairwise comparisons in an analysis of variance design). As shown in Table 1, neuroticism is significantly correlated, in the theoretically expected direction, with perceived stress and all of the mental and physical health variables. Those who have higher neuroticism scores rate themselves as more stressed
and as less physically healthy, have more depressive symptomatology and lower psychological well-being, and report having more chronic health conditions diagnosed by a doctor. Although not relevant for this study, the NEO-FFI factor Extraversion was significantly correlated with CES-D (r = -.37, p < .01), HPQ (r= .31, p < .05), health index (r = .37, p < .01), and number of chronic conditions (r = — .37, p < .01). The NEO-FFI factor Conscientiousness was negatively correlated with number of chronic conditions (r = -.35, p < .01). The NEO-FFI factors of Openness to Experience and Agreeableness were not significantly correlated with any of the mental or physical health measures. Optimism is significantly correlated, in the theoretically expected direction, with perceived stress and the mental health variables, but not with the physical health variables. Those who score highly on a scale of optimism rate themselves as less stressed, have fewer symptoms of depression, and have higher psychological well-being. To test the hypothesis that personality would be related to health outcomes directly, and indirectly through the effect of personality on perceived stress, we conducted path analyses. Figure 1 shows a diagram of the conceptual model being tested. In this study, all of the variables are measured (i.e., there are no latent variables). Therefore, as stated by Loehlin (1987): "So long as all variables are measured one can proceed to solve for the causal paths in a path diagram as beta weights in a series of multiple regression analyses" (p. 14). Cohen and Cohen (1983) described how to obtain partitioning of effects using hierarchical regression analyses. The regression coefficient when the variable first enters the hierarchy is its total effect. The regression coefficient in the final equation is, as always, its direct effect. The difference between the total and direct effects is the (total) indirect effect. . . . The indirect effect can be further partitioned in a hierarchical analysis by determining the change in each coefficient as a new variable is added to the equation. (Cohen & Cohen, 1983, pp. 360-361) Indirect effects can also be calculated as the product of paths. In this study the indirect effects of personality on health can be calculated by multiplying the path coefficient from personality
Table 1 Correlations Between Personality, Perceived Stress, and Mental and Physical Health Measure 1. Neuroticism (NEO-FFI) 2. Optimism (LOT) 3. Perceived stress (PSS) 4. CES-D 5. Bradburn affect balance 6. Current health (HPQ) 7. Health index 8. Number of diagnosed chronic conditions
1 — -.57**** .65**** -.50** — .75**** -.58*** .86**** — -.67**** .37* -.60**** -.57**** -.36" -.39** .15 -.43*** -.47*** -.47*** -.54**** .26
.44***
-.17
.29*
.43**
— .50*** — .35** .71****
—
-.35** -.52*** -.49*** —
Note. Ns ranged from 49 to 51. High scores represent more of the construct represented (e.g., high scores on the CES-D refer to greater depressive symptomatology). NEO-FFI = NEO Five Factor Index (Costa & McCrae, 1989); LOT = Life Orientation Test (Scheier & Carver, 1985); PSS = Perceived Stress Scale (Cohen, Karmarck, & Mermelstein, 1983); CES-D « Center for Epidemiologic Studies Depression Index (Radloff, 1977); HPQ = Health Perceptions Questionnaire (Davies & Ware, 1981). * p < .05 (two-tailed) ** p < .01 (two-tailed) *** p < .001 (two-tailed) **** p < .0001 (two-tailed)
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PERSONALITY AND CAREGIVING PERSONALITY,
MEOTAL HEALTH OR
PHYSICAL HEALTH
PERCEIVED STRESS
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Figure 1. Path model of the relations among personality, perceived stress, and mental or physical health. to stress (beta- 2 in Figure 1) with the path coefficient from stress to health (beta- 3 in Figure 1). Thus, personality variables and perceived stress were regressed on the outcome variables in two series of analyses. In the first series, five analyses were run in which each outcome variable was regressed on neuroticism and perceived stress in order to calculate direct and indirect effects. In the second series, the same analyses were conducted using optimism, rather than neuroticism, in the regressions. The direct and indirect path coefficients for the effect of personality on health outcomes are shown in Table 2. The total effects are, of course, represented in the correlations in Table 1.
cal health outcomes. For the mental health outcomes there were significant direct effects of perceived stress, and thus the indirect effect of neuroticism on mental health through its association with perceived stress was also quite strong. In fact, approximately one half of the total effects of neuroticism on mental health outcomes in the sample were due to indirect effects. In contrast, there were no significant direct effects of perceived stress on physical health outcomes. That is, there were no unique contributions due to perceived stress once neuroticism was partialed out of the equations. Thus, the indirect effects of neuroticism on physical health through perceived stress were also comparatively small. The adjusted percentage of variance explained in each of the five regressions ranged from 16% (for number of chronic conditions) to 79% (for CES-D scores). Neuroticism was significantly related to all of the health outcomes, independently of perceived stress. In addition, there were substantial indirect effects of neuroticism on mental health because of the association of neuroticism with perceived stress. Thus, in addition to the negative association of neuroticism alone on reported health outcomes, individuals who score highly on a neuroticism scale are more likely to perceive themselves as currently being under more stress, which in turn is associated with poor ratings of mental health.
Neuroticism
Optimism
As shown by the path coefficients in Table 2, there is a significant direct effect of neuroticism on all of the mental and physi-
In contrast with the results with neuroticism, the only significant direct effect of optimism on any of the outcomes was in the
Table 2 Path Coefficients for the Analysis of Personality, Perceived Stress, and Mental and Physical Health
Personality scale
Personality to health: 0,
Personality to perceived stress: /32
Perceived stress to health: 0,
Indirect path*— Personality to health through perceived stress: 02 x /33
Adjusted overall R2
Mental Health CES-D Neuroticism Optimism Affect balance Neuroticism Optimism
.32*** -.20*
.65*** -.50***
.65*** .76***
.42 -.38
.79*** .76***
-.32* .09
.65*** -.50***
-.40** -.56***
-.26 .28
.39*** .34***
Physical Health HPQ Neuroticism Optimism Health index Neuroticism Optimism Number of chronic conditions Neuroticism Optimism
-.34* -.04
.65*** -.50***
-.14 -.38*
-.09 .19
.17** .10*
-.41** .04
.65*** -.50***
-.20 -.45**
-.13 .23
.29*** .19**
.43** -.04
.65*** -.50***
.01 .28
.01 -.14
.16** .05
Note. CES-D = Center for Epidemiological Studies Depression Index (Rudloff, 1977); HPQ = Health Perceptions Questionnaire. * Significance levels are not reported for indirect paths (Cohen & Cohen, 1983). * p
