Short Reports

Rena R. Wing, PhD Marsha D. Marcus, PhD Elaine H. Blair, PhD Leonard H. Epstein, PhD Lisa R. Burton, BS

Depressive Symptomatology in Obese Adults With Type II Diabetes This study compared depressive symptomatology in 32 obese subjects with type II (non-insulin-dependent) diabetes (16 men, 16 women) and their obese nondiabetic spouses. All subjects completed the Beck Depression Inventory (BDI) before participation in a behavioral weight-loss program. Diabetic subjects reported significantly more depressive symptomatology than their overweight nondiabetic spouses (10.6 ± 6.4 vs. 7.5 ± 6.2, P < 0.04). Diabetic subjects scored higher than their spouses on 15 of 20 BDI items, with significant differences in feelings of being punished, perceived appearance, and interest in sex. Mean BDI score in the diabetic spouses was similar to that observed in the first 123 diabetic subjects to enter the weight-loss program (BDI 11.2 ± 6.9). Further studies are needed to determine whether diabetic subjects differ from age-, sex-, and weight-matched nondiabetic individuals in clinical depression and depressive symptomatology. Diabetes Care 13:170-72, 1990

ecent studies suggest that individuals with diabetes report significant levels of depressive symptomatology (1). However, there have been no studies to date comparing depressive symptomatology in diabetic and nondiabetic control subjects. The purpose of this study was to compare depressive symptomatology in obese type II (non-insulin-dependent) diabetic subjects and their nondiabetic spouses of comparable age, weight, and sex distribution.

R 170

RESEARCH DESIGN AND METHODS Thirty-two obese type II diabetic subjects (16 men, 16 women) were compared with their obese nondiabetic spouses. These subjects, referred to as the spouse sample, agreed to participate in a behavioral weight-loss program with their spouses. To obtain a sample with an equal number of men and women, 32 diabetic subjects were randomly selected from a total sample of 36 diabetic subjects participating with their spouses. As shown in Table 1, diabetic subjects and spouses did not differ significantly in age, weight, or percentage overweight. To determine the generalizability of these results, depressive symptomatology was also assessed in a separate cohort of 123 type II diabetic subjects (34 men, 89 women). These subjects were the first 123 subjects to be recruited to our behavioral weight-loss program for adults with diabetes (referred to as the general sample). The general sample was similar to diabetic subjects in the spouse sample in age, weight, and HbA, but had lower fasting glucose levels, a larger proportion of women, and differed in the distribution of subjects on diet, oral medication, and insulin. The spouse and general samples were recruited by newspaper advertisements and physician referrals. Subjects were required to be 30-70 yr of age, to be s:20% above ideal body weight, and to meet the National Diabetes Data Group criteria for type II diabetes. All subjects who were willing to attend group meetings weekly

DIABETES CARE, VOL. 13, N O . 2, FEBRUARY 1990

SHORT REPORTS

TABLE 1 Characteristics of subjects and overall BDI scores Spouse sample

Nondiabetic 32 16/16 M/F (n) 50.8 ± 8.8 Age (yr) 92.2 ± 14.0 Weight (kg) 5.7 ± 0.5 FBG (mM) 6.7 ± 0.5 HbA, (%) Years since diagnosis Percent overweight 40 ± 21 Percent on diet/oral insulin 7.5 ± 6.2 BDI total score Percent of subjects 12.5 with BDI S16 n

Type II diabetic

Genera sample

16/16 52.1 ± 7.7 99.6 ± 20.9 12.4 ± 4.4t 10.1 ± 2.3t 5.7 ± 5.4 51 ± 25

123 34/89* 53.5 dt 8.0 98.0 dt 17.6 10.6 dt 3.5* 9.8 dt 2.0 6.5 dt 5.8 60 dt 27

28/44/28 10.6 ± 6.4*

21/60/19* 11.2 : t 6.9

32

21.8

: >4

Values are means ± SD. BDI, Beck Depression Inventory; FBG, fasting blood glucose. *P < 0.05 compared with diabetic subjects in spouse sample. tP < 0.001, *P < 0.05, compared with nondiabetic spouses.

for 20 wk and to deposit $85 for participation in the program were accepted. Depressive symptomatology was assessed before entry into the behavioral weight-loss program with the Beck Depression Inventory (BDI), a widely used self-report instrument that assesses the severity of neurovegetative, cognitive, and affective symptoms of depression (2). The question on the BDI related to recent weight change was excluded from analysis. Paired t tests were used to compare diabetic subjects and their spouses and unpaired t tests to compare the general and spouse samples. x2-Tests were used to compare the frequency of moderate or severe depression.

RESULTS Diabetic subjects in the spouse sample reported significantly higher levels of depressive symptomatology at baseline than did their nondiabetic spouses (10.6 ± 6.4 vs. 7.5 ± 6.2, P < 0.04). Seven (21.8%) diabetic subjects reported moderate or severe depression (BDI ^16) compared to four (12.5%) of the nondiabetic spouses (NS). Because the BDI assesses somatic components of depression as well as cognitive and affective components, and because some of the somatic components (e.g., decreased interest in sex and difficulty sleeping) might be related to diabetes, differences between diabetic subjects and nondiabetic spouses were assessed for each item of the BDI (Table 2). Diabetic subjects had higher mean scores than their spouses on 15 of 20 BDI items, with significant differences in feelings of being punished, perceived appearance, and interest in sex.

DIABETES CARE, VOL. 13, NO. 2, FEBRUARY 1990

Results from the general sample confirm the findings reported above. Again, subjects reported substantial depressive symptomatology (average BDI score 11.2 ± 6.9), with 24% of the subjects reporting moderate or severe depressive symptomatology (BDI 5:16). These results did not differ significantly from those reported for diabetic subjects in the spouse sample.

DISCUSSION

T

his study suggests that overweight diabetic subjects report more depressive symptomatology than their overweight nondiabetic spouses. Although caution should be used in interpreting the itemby-item comparison, because some comparisons could be significant by chance alone, it appears that the difference in total BDI scores was due not only to differences in neurovegetative symptoms that may be secondary to diabetes (such as decreased interest in sex) but also to differences in cognitive symptoms of depression and greater dissatisfaction with physical appearance, symptoms that are less likely to be due to diabetes. In addition, the BDI scores of diabetic subjects in the spouse sample did not differ significantly from scores of diabetic subjects in the larger general sample, indicating the generalizability of these findings. In both the spouse and general sample, >20% of the diabetic subjects reported moderate or severe depressive symptomatology (BDI >16). Given evidence for assortative mating and the fact that

TABLE 2 Scores on individual items of Beck Depression Inventory (BDI) of diabetic subjects and their spouses BDI item Feel sad Discouraged about future Feel like failure Get satisfaction out of things Feel guilty Feel I'm being punished Feel disappointed in self Critical of self Thoughts of killing self Crying Feel irritated Lost interest in others Decision making Perceived appearance Effort to work Ability to sleep Feel tired Appetite Worry about health Interest in sex

Diabetic subjects 0.22 0.28 0.41 0.59 0.19 0.37 0.62 0.62 0.09 0.22 0.81 0.31 0.66 1.06 0.81 0.75 1.16 0.00 0.63 0.78

± ± ± ± ± dt dt dt dt dt dt dt dt dt dt d: ± ± ± ±

0.49 0.52 0.61 0.56 0.47 0.79 0.71 0.61 0.30 0.61 0.64 0.53 0.79 1.04 0.60 0.88 0.57 0.00 0.71 0.91

Spouses 0.25 ± 0.31 ± 0.19 ± 0.44 ± 0.19 ± 0.06 :t 0.53 :t 0.37 dt 0.00 dt 0.19 dt 0.59 dt 0.47 dt 0.38 dt 0.44 dt 0.69 dt 0.66 dt 0.91 dt 0.06 dt 0.41 ± 0.34 ±

0.51 0.59 0.47 0.62 0.40 0.25 0.62 0.49 0.00 0.40 0.61 0.62 0.61 0.62 0.74 0.79 0.64 0.25 0.61 0.70

P

0.11

0.04 0.09 0.08 0.11 0.11 0.01

0.04

Values are means ± SD.

171

SHORT REPORTS

living with a depressed person can be distressing, the use of spouses as a control group may have underestimated the differences between diabetic and nondiabetic subjects (3,4). Therefore, further studies comparing overweight type II diabetic subjects with age-, sex-, and weight-matched unrelated individuals would be of interest. In addition, this study used only the BDI and examined depressive symptomatology but not clinical depression. Previous studies have shown that major depression occurs frequently in adults with type I (insulin-dependent) and type II diabetes, and these depressions tend to run a chronic course (1,5,6). Therefore, it would be interesting to compare diabetic and nondiabetic subjects with multiple measures of depression and to compare the prevalence of both current and lifetime history of depression. This would help determine whether the differences observed in this study represent clinically significant differences. Finally, it is important to determine the variables related to depressive symptomatology in diabetic individuals and the interrelationship between depression and diabetes therapy. Lustman et al. (1) have suggested that the onset of clinical depression in type II diabetic subjects often precedes the development of diabetes and that depression and diabetes may interact at a basic biologic level. Patients with a history of major depression have poorer glycemic control, but there have been no studies to determine whether improvements in glycemic control, produced by intensive insulin therapy or weight loss in obese type II diabetic subjects, would have an impact on depressive symptomatology or whether treating patients for their depression would improve response

to diabetes treatment (5). Such studies are clearly warranted. From the Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania. Address correspondence and reprint requests to Rena R. Wing, PhD, Western Psychiatric Institute and Clinic, 3811 O'Hara Street, Pittsburgh, PA 15213. Received for publication 20 March 1989 and accepted in revised form 4 October 1989.

ACKNOWLEDGMENTS

This research was supported by Grant AM-29757 from the National Institute of Diabetes and Digestive and Kidney Diseases. REFERENCES

1. Lustman PJ, Griffith LS, Glouse RE: Depression in adults with diabetes: results of 5-yr follow-up study. Diabetes Care 11:605-12, 1988 2. Beck AT, Beck RW: Screening depressed subjects in family practice: a rapid technic. Postgrad Med 52:81-85, 1972 3. Merikangas KR, Bromet EJ, Spiker DG: Assortative mating, social adjustment, and course of illness in primary affective disorder. Arch Cen Psychiatry 40:795-800, 1983 4. Coyne JC, Kessler RC, Tal M, Turnbull J, Wortman CB, Greden JF: Living with a depressed person. J Consult Clin Psychol 55:347-52, 1987 5. Lustman PJ, Griffith LS, Clouse RE, Cryer PE: Psychiatric illness in diabetes mellitus: relationship to symptoms and glucose control. / Nerv Merit Dis 174:736-42, 1986 6. Popkin MK, Callies AL, Lentz RD, Colon EA, Sutherland DE: Prevalence of major depression, simple phobia, and other psychiatric disorders in subjects with long-standing type I diabetes mellitus. Arch Cen Psychiatry 45:64-68, 1988

Blood Glucose Area Under the Curve Methodological Aspects To specify the influence of methods used in estimating area under the curve (AUC) and the meaning of total and incremental AUC, 75 glycemic responses to a mixed meal were studied in 75 diabetic patients, 39 with insulin-dependent diabetes mellitus and 36 with non-insulin-dependent diabetes mellitus. AUC was integrated with five computerized methods: polynomial interpolation of third and fourth degree, trapezoidal rule, Simpson's integration, and cubic interpolatory splines. Although these methods gave significantly different results (P < 0.001), a strong correlation was found between estimations of AUC with different methods (r > 0.99, P < 0.001). In addition, variation between methods was