Table 2.
Characteristics of the study population of depressed older adults (N = 283)
| Course of Depression | ||||||
|---|---|---|---|---|---|---|
| Total study population | Remitted depression (n = 53) | Intermittent depression (n = 57) | Chronic depression (n = 173) | χ2 (df) or F (df between; df within)a | P‐Value | |
| Demographic characteristics | ||||||
| Female gender, n (%) | 186 (65.7%) | 31 (58.5%) | 37 (64.9%) | 118 (68.2%) | χ2 = 1.72 (2) | .42 |
| Age, years, mean (SD) | 70.4 (7.2) | 68.3 (6.3)b | 71.8 (7.6)b | 70.5 (7.3) | F = 3.32 (2; 282) | .04 |
| Educational level | χ2 = 7.69 (4) | .10 | ||||
| Basic, n (%) | 54 (19.1%) | 5 (9.4%) | 9 (15.8%) | 40 (23.1%) | ||
| Intermediate, n (%) | 162 (57.2%) | 38 (71.7%) | 33 (57.9%) | 91 (52.6%) | ||
| High, n (%) | 67 (23.7%) | 10 (18.9%) | 15 (26.3%) | 42 (24.3%) | ||
| Psychological variables | ||||||
| DSM‐IV diagnosis at baseline | χ2 = 14.74 (6) | .02 | ||||
| Minor depression, n (%) | 10 (3.5%) | 2 (3.8%) | 4 (7.0%) | 4 (2.3%) | ||
| Major depression, n (%) | 200 (70.7%) | 44 (83.0%) | 43 (75.4%) | 113 (65.3%) | ||
| Dysthymia, n (%) | 5 (1.8%) | 0 (0.0%) | 2 (3.5%) | 3 (1.7%) | ||
| Double diagnosis, n (%) | 68 (24.0%) | 7 (13.2%) | 8 (14.0%) | 53 (30.6%) | ||
| DSM‐IV diagnosis at follow‐up, n (%) | 163 (57.6%) | 15 (28.3%) | 28 (49.1%) | 120 (69.4%) | χ2 = 30.12 (2) | < .001 |
| Severity of depressive symptoms, IDS score, mean (SD) | 29.5 (12.9) | 21.7 (13.1)c | 20.8 (9.7)d | 34.7 (10.9)c , d | F = 49.21 (2; 279) | < .001 |
| Somatic and lifestyle variables | ||||||
| Antidepressant use, n (%) | 209 (73.9%) | 45 (84.9%) | 40 (70.2%) | 124 (71.7%) | χ2 = 4.18 (2) | .12 |
| Functional limitations, WHO‐DAS score, mean (SD) | 31.9 (15.7) | 24.6 (14.4)e | 25 (13.4)f | 36.4 (15.2)e , f | F = 20.72 (2; 277) | < .001 |
| Number of chronic diseases, mean (SD) | 2.1 (1.5) | 1.5 (1.3)g | 1.9 (1.3) | 2.4 (1.6)g | F = 9.26 (2; 281) | < .001 |
| Cognitive status, MMSE score, mean (SD) | 28.0 (1.7) | 28.2 (1.5) | 28.1 (1.4) | 27.9 (1.8) | F = 0.73 (2; 281) | .48 |
| Lifestyle factors | ||||||
| Physical exercise, IPAQ score, mean (SD) | 2604.7 (2518.1) | 2479.7 (2062.8) | 3065.1 (2895.0) | 2498.6 (2513.3) | F = 0.95 (2; 235) | .39 |
| Sleep duration, hours | χ2 = 10.99 (4) | .03 | ||||
| 9 hours or more, n (%) | 56 (19.8%) | 9 (17.0%) | 14 (24.6%) | 33 (19.1%) | ||
| 7–8 hours, n (%) | 112 (39.6%) | 25 (47.2%) | 29 (50.9%) | 58 (33.5%) | ||
| 6 hours or less, n (%) | 115 (40.6%) | 19 (35.8%) | 14 (24.6%) | 82 (47.4%) | ||
| Alcohol use, AUDIT score | χ2 = 3.70 (4) | .45 | ||||
| Non‐drinker, n (%) | 100 (35.5%) | 16 (30.2%) | 16 (28.1%) | 68 (39.5%) | ||
| Moderate drinker, n (%) | 126 (44.7%) | 24 (45.3%) | 29 (50.9%) | 73 (42.4%) | ||
| At‐risk drinker, n (%) | 56 (19.9%) | 13 (24.5%) | 12 (21.1%) | 31 (18.0%) | ||
| BMI | χ2 = 13.50 (4) | .01 | ||||
| Underweight, n (%) | 12 (4.3%) | 2 (2.8%) | 0 (0.0%) | 10 (5.8%) | ||
| Overweight, n (%) | 158 (56.0%) | 21 (39.6%) | 31 (54.4%) | 106 (61.6%) | ||
| Normal weight, n (%) | 112 (39.7%) | 30 (56.6%) | 26 (45.6%) | 56 (32.6%) | ||
| Smoking status | χ2 = 6.91 (4) | .14 | ||||
| Never smoker, n (%) | 89 (31.7%) | 17 (32.7%) | 17 (30.4%) | 55 (31.8%) | ||
| Past smoker, n (%) | 126 (44.8%) | 29 (55.8%) | 27 (48.2%) | 70 (40.5%) | ||
| Current smoker, n (%) | 66 (23.5%) | 6 (11.5%) | 12 (21.4%) | 48 (27.7%) | ||
| Composite lifestyle index, mean (SD) | 10.4 (1.7) | 10.9 (1.8)h | 10.6 (1.7) | 10.4 (1.7)h | F = 3.78 (2; 282) | .02 |
Abbreviations: AUDIT, Alcohol Use Disorders Identification Test; BMI, body mass index; DSM‐IV, Diagnostic and Statistical Manual of Mental Disorders, fourth edition; IDS, Inventory of Depressive Symptomatology; IPAQ, International Physical Activity Questionnaire; MDD, major depressive disorder; N, number of participants; SD, standard deviation; WHO‐DAS, World Health Organization Disability Assessment Schedule.
P‐value for categorical variables: Pearson's χ 2 test; for continuous variables: analysis of variance. Post‐hoc analyses showed a significant difference between:
remitted and intermittent depression for age, P = .03;
remitted and chronic depression for depression severity score, P < .001;
intermittent and chronic depression for depression severity, P < .001;
remitted and chronic depression for functional limitations, P < .001;
intermittent and chronic depression for functional limitations, P < .001;
remitted and chronic depression for number of chronic diseases, P < .001;
remitted and chronic depression for composite lifestyle index, P = .003.