197
Psychfurry Research, 38: 197-200 Elsevier
Weight Change “Disinhibition” Variables
in Depression: Is Mediated
Influence by Body
Albert J. Stunkard, Madelyn H. Fernstrom, Ellen Frank, and David J. Kupfer
R. Arlen
of Mass
and Other
Price, Emily Buss,
Received January 29, 1991; revised version received June 17, 1991; accepted July 14, 1991. Abstract. The direction of weight change (gain or loss) in depression has recently been found to be a stable characteristic of patients across depressive episodes. A search for determinants of the direction of weight change revealed two candidates: the body mass index (BMI) (weight in kilograms/ height in meters squared) and a psychological variable, “disinhibition” ofdietary restraint. The present study, of 68 patients with a history of recurrent depression, found a significant correlation between BMI and weight change; in other words, heavier persons were more likely to gain weight if depressed. There was also a correlation between “disinhibition” and weight change. “Disinhibition” correlated with BMI and, when controlled for BMI, age and sex, the correlation between “disinhibition” and weight change fell to insignificance. We conclude that BMI along with age and sex mediated the correlation between “disinhibition” and weight change.
Key Words.
Depression,
weight change,
body mass index, disinhibition.
and extent of weight change during depression has recently been found to be a stable patient characteristic with a high degree of concordance across depressive episodes (Stunkard et al., 19904. It can therefore be regarded as a potential marker or characteristic of subtypes of depression. Efforts to establish the determinants of the direction and extent of weight change in depression have included two psychometric measures: dietary “restraint,” a measure that discriminates dieting, weight-conscious individuals from nondieters (Herman and Polivy, 1980), and “disinhibition” of such dietary restraint (Stunkard and Messick, 1985). Polivy and Herman (1976) reported that college students who scored high on their Restraint Scale recalled gaining weight during depressive moods, while those who scored low on the Restraint Scale recalled losing weight during depressive moods. Zielinsky (1978) also noted that patients who scored high on the Restraint Scale reported that they gained weight when they were depressed. A more recent psychometric assessment of eating behavior by
The direction
Albert J. Stunkard, M.D., is Professor of Psychiatry, Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA. Madelyn H. Fernstrom, Ph.D., is Associate Professor of Psychiatry and Epidemiology, Department of Psychiatry, University bf Pittsburgh School of Medicine, Pittsburgh, PA. R. Arlen Price, Ph.D., is Associate Professor of Psychology in Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA. Emily Buss, B.A., is Research Assistant to Dr. Stunkard, University of Pennsylvania School of Medicine, Philadelphia, PA. Ellen Frank, Ph.D., is Associate Professor of Psychology in Psychiatry, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA. David J. Kupfer, M.D., is Professor and Chairman, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA. (Reprint requests to Dr. A.J. Stunkard, 133 S. 36th St., Philadelphia, PA 19104-3246, USA). 0165-1781/91/$03.50
@ 1991 Elsevier Scientific Publishers Ireland Ltd.
198 Stunkard and Messick (1985) defined three factors: dietary “restraint,” “disinhibition” of this restraint, and “hunger.” In 1986 Weissenburger et al. found that scores on the “disinhibition” factor showed a correlation (0.35, p < 0.001) with measured weight change in 109 patients during the course of severe, medically diagnosed depressions. The relationship of “disinhibition” to weight change during depression was reexamined in the present study, which also assessed the influence of body weight and other variables.
Methods The data for the present analysis were obtained from 68 patients enrolled in the Pittsburgh Study of Maintenance Therapy of Depression (Frank and Kupfer, 1985). These patients had suffered from at least three episodes of depression severe enough to require medical attention, without comorbidity and with a minimum score of 15 on the Hamilton Rating Scale for Depression (Hamilton, 1960) and a minimum score of 7 on the Raskin scale (Raskin et al., 1969). Information collected from each patient, before any use of antidepressant medication, included body mass index (BMI = weight in kilograms/ height in meters squared), age, duration of depression, and “disinhibition”as measured on the Eating Inventory (Stunkard and Messick, 1985). In addition, patients were interviewed for about half an hour according to a semistructured schedule (available on request). In this interview, they were asked about the direction and magnitude (in pounds) of weight change during their depressive episodes. Patients completed a IO-cm visual analogue scale that measured the intensity of their appetite when they were depressed. Measured weight changes, available for 22 patients, corresponded closely to reported weight changes. Only data from the most recent episode of depression were used in the analyses presented here. Linear regression residuals were computed to adjust correlations for BMI. Pearson product-moment correlations of these data were then performed to identify variables associated with the direction and extent of weight change, both before and after control for BMI, age, age squared, and gender.
Results of weight change was correlated with BMI (r = 0.30, p < 0.05). Table 1 presents the correlation between the variables of interest, both unadjusted (above the main diagonal) and after adjustment for BMI, age, and gender (below the main diagonal). The high correlation of appetite with weight change (0.76,~ < 0.000 1 before
The extent
Table 1. Correlation
matrix of weight change and related variables Appetite
Duration
Disinhibition
Weight change
0.322 -
0.07
0.483
0.301
Appetite
0.18
0.34’
0.763
Duration
0.18
0.20
Disinhibition
0.341
0.19
0.19 -
Weight change
0.653
0.19
0.12
Body Mass Index
-
Note. Above the main diagonal are the unadjusted correlations. Below thediagonal Body Mass Index. age, age squared, and sex. 1. p < 0.05. 2. p < 0.01. 3. p < 0.0001.
0.352 arecorrelations
adjusted for
199 correction; 0.65, p < 0.0001 after correction) provides a measure of the internal consistency of the findings of the study. The significant correlations of BMI with appetite and “disinhibition,” as well as weight change, suggests the importance of this variable in the relationships depicted in Table 1. The correlations between severity of depression and weight change (r = -0.20) and appetite (r = -0.08) did not reach statistical significance. Before control for BMI, age, and sex, “disinhibition”showed a correlation with weight change of 0.35 @ < 0.01). Control for these variables produced one major change: the correlation between “disinhibition” and weight change fell dramatically, from a significant 0.35 to a nonsignificant 0.12. The correlations between appetite and both “disinhibition” and weight change were not affected by the controls, and remained statistically significant.
Discussion Both patient care and research are placing increasing demands on psychiatric nosology. A key requirement of a diagnosis is its stability over time and across clinical episodes. A blow to diagnosis in depression was the finding that there is no greater consistency of the diagnosis of endogenous depression from one episode to the next than would be expected by chance (Young et al., 1987). In these circumstances, the finding of stability of weight change across depressive episodes (Stunkard et al., 1990~) takes on added importance. A search for the determinants of the direction of weight change in depression had suggested that a psychometric measure, “disinhibition” of dietary restraint, might serve this role. In the Weissenburger et al. (1986) study of 109 severely depressed persons, the correlation between “disinhibition” and weight loss was 0.35 (p < O.OOl), identical to 0.35 (p < 0.01) of the present study. This correlation had been interpreted as indicating that “disinhibition” determines the direction and extent of weight change in depression. The introduction of controls for BMI and other variables in the present study revealed a more complex relationship. Correlation between “disinhibition” and weight change was mediated by the correlation of each with BMI, age, and sex. If not disinhibition, what determines the direction and extent of weight change in depression? BMI is a candidate with strong intuitive appeal, correlating 0.30 with weight change, but this relationship is clearly a weak one, accounting for no more than 9% of the variance. Genetic influences may well contribute to the direction of weight change, as they do to the BMI (Stunkard et al., 1986,19906; Priceet al., 1991), and we are currently investigating this possibility. Whatever its determinants, direction of weight change in depression appears to be a potential marker or characteristic of subtypes of depression. Acknowledgment. This study was supported in part by grants from the John D. and Catherine T. MacArthur Foundations; by National lnstitute of Mental Health research grants MH-29618, MH-31050, and MH-41644; and by a Research Scientist Award to Dr. Stunkard.
200 References Frank, E., and Kupfer, D.J. Maintenance treatment of unipolar depression: Pharmacology and psychotherapy. In: Kemali, D., and Racagni, G., eds. Chronic Treatments in Neuropsychiatry. New York: Raven Press, 1985. pp. 139-151. Hamilton, M. A rating scale for depression. Journal of Neurology, Neurosurgery and Psychiatry, 23:X-62, 1960. Herman, C.P., and Polivy, J. Restrained eating. In: Stunkard, A.J., ed. Obesity. Philadelphia: Saunders, 1980. pp. 208-225. Polivy, J., and Herman, C.P. Clinical depression and weight change: A complex relation. Journal of Abnormal Psychology, 85:338-340, 1976. Price, R.A.; Ness, R.; and Laskarzewski, P. Common major gene inheritance of extreme overweight. Human Biology, 621747-765, 199 1. Raskin, A.; Schuherbrandt, J.; Reatig, N.; and McKeon, J.J. Replication of factors of psychopathology in interview, ward behavior, and self-report ratings of hospitalized depressives. Journal of Nervous and Mental Disease. 148:87-98, 1969. Stunkard, A.J.; Fernstrom, M.H.; Price, R.A.; Frank, E.; and Kupfer, D.J. Direction of weight change in recurrent depression: Consistency across episodes. Archives of General Psychiatry, 47:857-860, 1990a. Stunkard, A.J.; Harris, J.R.; Pedersen, N.L.; and McClearn, G.E. The body-mass index of twins who have been reared apart. New England Journal of Medicine, 322: 1483-1487, 19906. Stunkard, A.J., and Messick, S. The Three-Factor Eating Questionnaire to measure dietary restraint, disinhibition and hunger. Journal of Psychosomatic Research, 29:71-83, 1985. Stunkard, A.J.; Sorensen, T.I.A.; Hanis, C.; Teasdale, T.W.; Chakraborty, R.; Schull, W.J.; and Schulsinger, F. An adoption study of human obesity. New England Journal qf Medicine. 314:193-198, 1986. Weissenburger, J.; Rush, A.J.; Giles, D.E.; and Stunkard, A.J. Weight change in depression. Psychiatry Research, 17:275-283. 1986. Young, M.A.; Keller, M.B.; Lavori, P.B.; Scheffner, W.A.; Fawcett, J.A.; Endicott, J.; and Hirschfeld, R.M.A. Lack of stability of the endogenous subtype in consecutive episodes of major depression. Journal of Affective Disorders, 12: I39- 149, 1987. Zielinsky, J.J. Depressive symptomatology: Deviation from a personal norm. Journal of Community Psychology, 6: I63- 168, 1978.
Psychfurry Research, 38: 197-200 Elsevier
Weight Change “Disinhibition” Variables
in Depression: Is Mediated
Influence by Body
Albert J. Stunkard, Madelyn H. Fernstrom, Ellen Frank, and David J. Kupfer
R. Arlen
of Mass
and Other
Price, Emily Buss,
Received January 29, 1991; revised version received June 17, 1991; accepted July 14, 1991. Abstract. The direction of weight change (gain or loss) in depression has recently been found to be a stable characteristic of patients across depressive episodes. A search for determinants of the direction of weight change revealed two candidates: the body mass index (BMI) (weight in kilograms/ height in meters squared) and a psychological variable, “disinhibition” ofdietary restraint. The present study, of 68 patients with a history of recurrent depression, found a significant correlation between BMI and weight change; in other words, heavier persons were more likely to gain weight if depressed. There was also a correlation between “disinhibition” and weight change. “Disinhibition” correlated with BMI and, when controlled for BMI, age and sex, the correlation between “disinhibition” and weight change fell to insignificance. We conclude that BMI along with age and sex mediated the correlation between “disinhibition” and weight change.
Key Words.
Depression,
weight change,
body mass index, disinhibition.
and extent of weight change during depression has recently been found to be a stable patient characteristic with a high degree of concordance across depressive episodes (Stunkard et al., 19904. It can therefore be regarded as a potential marker or characteristic of subtypes of depression. Efforts to establish the determinants of the direction and extent of weight change in depression have included two psychometric measures: dietary “restraint,” a measure that discriminates dieting, weight-conscious individuals from nondieters (Herman and Polivy, 1980), and “disinhibition” of such dietary restraint (Stunkard and Messick, 1985). Polivy and Herman (1976) reported that college students who scored high on their Restraint Scale recalled gaining weight during depressive moods, while those who scored low on the Restraint Scale recalled losing weight during depressive moods. Zielinsky (1978) also noted that patients who scored high on the Restraint Scale reported that they gained weight when they were depressed. A more recent psychometric assessment of eating behavior by
The direction
Albert J. Stunkard, M.D., is Professor of Psychiatry, Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA. Madelyn H. Fernstrom, Ph.D., is Associate Professor of Psychiatry and Epidemiology, Department of Psychiatry, University bf Pittsburgh School of Medicine, Pittsburgh, PA. R. Arlen Price, Ph.D., is Associate Professor of Psychology in Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA. Emily Buss, B.A., is Research Assistant to Dr. Stunkard, University of Pennsylvania School of Medicine, Philadelphia, PA. Ellen Frank, Ph.D., is Associate Professor of Psychology in Psychiatry, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA. David J. Kupfer, M.D., is Professor and Chairman, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA. (Reprint requests to Dr. A.J. Stunkard, 133 S. 36th St., Philadelphia, PA 19104-3246, USA). 0165-1781/91/$03.50
@ 1991 Elsevier Scientific Publishers Ireland Ltd.
198 Stunkard and Messick (1985) defined three factors: dietary “restraint,” “disinhibition” of this restraint, and “hunger.” In 1986 Weissenburger et al. found that scores on the “disinhibition” factor showed a correlation (0.35, p < 0.001) with measured weight change in 109 patients during the course of severe, medically diagnosed depressions. The relationship of “disinhibition” to weight change during depression was reexamined in the present study, which also assessed the influence of body weight and other variables.
Methods The data for the present analysis were obtained from 68 patients enrolled in the Pittsburgh Study of Maintenance Therapy of Depression (Frank and Kupfer, 1985). These patients had suffered from at least three episodes of depression severe enough to require medical attention, without comorbidity and with a minimum score of 15 on the Hamilton Rating Scale for Depression (Hamilton, 1960) and a minimum score of 7 on the Raskin scale (Raskin et al., 1969). Information collected from each patient, before any use of antidepressant medication, included body mass index (BMI = weight in kilograms/ height in meters squared), age, duration of depression, and “disinhibition”as measured on the Eating Inventory (Stunkard and Messick, 1985). In addition, patients were interviewed for about half an hour according to a semistructured schedule (available on request). In this interview, they were asked about the direction and magnitude (in pounds) of weight change during their depressive episodes. Patients completed a IO-cm visual analogue scale that measured the intensity of their appetite when they were depressed. Measured weight changes, available for 22 patients, corresponded closely to reported weight changes. Only data from the most recent episode of depression were used in the analyses presented here. Linear regression residuals were computed to adjust correlations for BMI. Pearson product-moment correlations of these data were then performed to identify variables associated with the direction and extent of weight change, both before and after control for BMI, age, age squared, and gender.
Results of weight change was correlated with BMI (r = 0.30, p < 0.05). Table 1 presents the correlation between the variables of interest, both unadjusted (above the main diagonal) and after adjustment for BMI, age, and gender (below the main diagonal). The high correlation of appetite with weight change (0.76,~ < 0.000 1 before
The extent
Table 1. Correlation
matrix of weight change and related variables Appetite
Duration
Disinhibition
Weight change
0.322 -
0.07
0.483
0.301
Appetite
0.18
0.34’
0.763
Duration
0.18
0.20
Disinhibition
0.341
0.19
0.19 -
Weight change
0.653
0.19
0.12
Body Mass Index
-
Note. Above the main diagonal are the unadjusted correlations. Below thediagonal Body Mass Index. age, age squared, and sex. 1. p < 0.05. 2. p < 0.01. 3. p < 0.0001.
0.352 arecorrelations
adjusted for
199 correction; 0.65, p < 0.0001 after correction) provides a measure of the internal consistency of the findings of the study. The significant correlations of BMI with appetite and “disinhibition,” as well as weight change, suggests the importance of this variable in the relationships depicted in Table 1. The correlations between severity of depression and weight change (r = -0.20) and appetite (r = -0.08) did not reach statistical significance. Before control for BMI, age, and sex, “disinhibition”showed a correlation with weight change of 0.35 @ < 0.01). Control for these variables produced one major change: the correlation between “disinhibition” and weight change fell dramatically, from a significant 0.35 to a nonsignificant 0.12. The correlations between appetite and both “disinhibition” and weight change were not affected by the controls, and remained statistically significant.
Discussion Both patient care and research are placing increasing demands on psychiatric nosology. A key requirement of a diagnosis is its stability over time and across clinical episodes. A blow to diagnosis in depression was the finding that there is no greater consistency of the diagnosis of endogenous depression from one episode to the next than would be expected by chance (Young et al., 1987). In these circumstances, the finding of stability of weight change across depressive episodes (Stunkard et al., 1990~) takes on added importance. A search for the determinants of the direction of weight change in depression had suggested that a psychometric measure, “disinhibition” of dietary restraint, might serve this role. In the Weissenburger et al. (1986) study of 109 severely depressed persons, the correlation between “disinhibition” and weight loss was 0.35 (p < O.OOl), identical to 0.35 (p < 0.01) of the present study. This correlation had been interpreted as indicating that “disinhibition” determines the direction and extent of weight change in depression. The introduction of controls for BMI and other variables in the present study revealed a more complex relationship. Correlation between “disinhibition” and weight change was mediated by the correlation of each with BMI, age, and sex. If not disinhibition, what determines the direction and extent of weight change in depression? BMI is a candidate with strong intuitive appeal, correlating 0.30 with weight change, but this relationship is clearly a weak one, accounting for no more than 9% of the variance. Genetic influences may well contribute to the direction of weight change, as they do to the BMI (Stunkard et al., 1986,19906; Priceet al., 1991), and we are currently investigating this possibility. Whatever its determinants, direction of weight change in depression appears to be a potential marker or characteristic of subtypes of depression. Acknowledgment. This study was supported in part by grants from the John D. and Catherine T. MacArthur Foundations; by National lnstitute of Mental Health research grants MH-29618, MH-31050, and MH-41644; and by a Research Scientist Award to Dr. Stunkard.
200 References Frank, E., and Kupfer, D.J. Maintenance treatment of unipolar depression: Pharmacology and psychotherapy. In: Kemali, D., and Racagni, G., eds. Chronic Treatments in Neuropsychiatry. New York: Raven Press, 1985. pp. 139-151. Hamilton, M. A rating scale for depression. Journal of Neurology, Neurosurgery and Psychiatry, 23:X-62, 1960. Herman, C.P., and Polivy, J. Restrained eating. In: Stunkard, A.J., ed. Obesity. Philadelphia: Saunders, 1980. pp. 208-225. Polivy, J., and Herman, C.P. Clinical depression and weight change: A complex relation. Journal of Abnormal Psychology, 85:338-340, 1976. Price, R.A.; Ness, R.; and Laskarzewski, P. Common major gene inheritance of extreme overweight. Human Biology, 621747-765, 199 1. Raskin, A.; Schuherbrandt, J.; Reatig, N.; and McKeon, J.J. Replication of factors of psychopathology in interview, ward behavior, and self-report ratings of hospitalized depressives. Journal of Nervous and Mental Disease. 148:87-98, 1969. Stunkard, A.J.; Fernstrom, M.H.; Price, R.A.; Frank, E.; and Kupfer, D.J. Direction of weight change in recurrent depression: Consistency across episodes. Archives of General Psychiatry, 47:857-860, 1990a. Stunkard, A.J.; Harris, J.R.; Pedersen, N.L.; and McClearn, G.E. The body-mass index of twins who have been reared apart. New England Journal of Medicine, 322: 1483-1487, 19906. Stunkard, A.J., and Messick, S. The Three-Factor Eating Questionnaire to measure dietary restraint, disinhibition and hunger. Journal of Psychosomatic Research, 29:71-83, 1985. Stunkard, A.J.; Sorensen, T.I.A.; Hanis, C.; Teasdale, T.W.; Chakraborty, R.; Schull, W.J.; and Schulsinger, F. An adoption study of human obesity. New England Journal qf Medicine. 314:193-198, 1986. Weissenburger, J.; Rush, A.J.; Giles, D.E.; and Stunkard, A.J. Weight change in depression. Psychiatry Research, 17:275-283. 1986. Young, M.A.; Keller, M.B.; Lavori, P.B.; Scheffner, W.A.; Fawcett, J.A.; Endicott, J.; and Hirschfeld, R.M.A. Lack of stability of the endogenous subtype in consecutive episodes of major depression. Journal of Affective Disorders, 12: I39- 149, 1987. Zielinsky, J.J. Depressive symptomatology: Deviation from a personal norm. Journal of Community Psychology, 6: I63- 168, 1978.
