Table 1.
Participants’ characteristics in a random sample at baseline, stratified by depression case status.
| Baseline characteristics | Sample | Depression casesa | Non-depressed individuals | P-value |
|---|---|---|---|---|
| (n=380) | (n=100) | (n=280) | ||
| Age at CTSC, median (IQR) | 64.9 (60.3 - 69.2) | 63.6 (58.8 - 66.9) | 65.3 (60.7 - 69.5) | 0.01b |
| Sex, n (%) | 0.73 | |||
| Male | 188 (49.5) | 48 (48.0) | 140 (50.0) | |
| Female | 192 (50.5) | 52 (52.0) | 140 (50.0) | |
| Race/ethnicity, n (%) | 0.98 | |||
| Non-Hispanic white | 297 (78.2) | 78 (78.0) | 219 (78.2) | |
| Black | 40 (10.5) | 11 (11.0) | 29 (10.4) | |
| Othersd | 43 (11.3) | 11 (11.0) | 32 (11.4) | |
| Education, n (%) | 0.49 | |||
| ≤college degree | 182 (48.0) | 51 (51.0) | 131 (47.0) | |
| Post-college education | 197 (52.0) | 49 (49.0) | 148 (53.1) | |
| Income, n (%) | 0.18 | |||
| <$50,000 | 77 (23.3) | 25 (28.4) | 52 (21.4) | |
| $50,000+ | 254 (76.7) | 63 (71.6) | 191 (78.6) | |
| BMI, kg/m2, median (IQR) | 27.5 (24.4 – 30.6) | 28.2 (25.1 - 31.6) | 27.3 (24.4 – 29.9) | 0.05b |
| PA,e MET-hours/week, median (IQR) | 21.5 (8.0 - 38.0) | 18.3 (7.2 - 30.6) | 21.7 (8.2 - 40.6) | 0.07b |
| Alcohol use, n (%) | 0.13 | |||
| Rare/never | 69 (19.3) | 25 (26.3) | 44 (16.7) | |
| Monthly | 32 (8.9) | 7 (7.4) | 25 (9.5) | |
| Weekly | 154 (43.0) | 42 (44.2) | 112 (42.6) | |
| Daily | 103 (28.8) | 21 (22.1) | 82 (31.2) | |
| Smoking use, n (%) | 0.03 | |||
| Never | 197 (52.1) | 42 (42.0) | 155 (55.8) | |
| Past | 163 (43.1) | 50 (50.0) | 113 (40.7) | |
| Current | 18 (4.8) | 8 (8.0) | 10 (3.6) | |
| History of hypertension,f n (%) | 177 (47.0) | 49 (49.5) | 128 (46.0) | 0.55 |
| History of diabetes,g n (%) | 44 (11.6) | 18 (18.2) | 26 (9.3) | 0.02 |
| History of high cholesterol, n (%) | 140 (36.8) | 42 (42.0) | 98 (35.0) | 0.21 |
| PHQ-9 score, median (IQR) | 1.0 (0.0 - 2.0) | 1.0 (0.0 - 3.0) | 0.0 (0.0 - 2.0) | 0.001b |
| SSRI users, n (%) | 18 (4.8) | 12 (12.0) | 6 (2.2) | <0.001 |
| Serum BDNF, ng/mL, mean (SD) | 36.3 (7.5) | 37.4 (7.2) | 36.0 (7.5) | 0.11c |
| Randomization to vitamin D3 group, n (%) | 0.95 | |||
| Active | 189 (49.7) | 50 (50.0) | 139 (49.6) | |
| Placebo | 191 (50.3) | 50 (50.0) | 141 (50.4) | |
| Randomization to omega-3s group, n (%) | 0.95 | |||
| Active | 191 (50.3) | 50 (50.0) | 141 (50.4) | |
| Placebo | 189 (49.7) | 50 (50.0) | 139 (49.6) |
Abbreviation: BDNF, brain-derived neurotrophic factor; BMI, body mass index; PA, physical activity; PHQ, patient health questionnaire; CTSC, clinical and translational science center; IQR, interquartile range.
Depression cases include current, past, or recurrent major depressive disorder, current or past major depressive episodes and dysthymia.
Wilcoxon-rank sum test was performed.
Two-sample t-test was performed.
Others race/ethnicity group included Hispanics, Asians and Other (Native Hawaiian or other Pacific Islander, multiple race, unknown race, or unknown ethnicity).
Leisure-time physical activities include walking or hiking; jogging; running; bicycling; aerobic exercise/aerobic dance/exercise machines; lower intensity exercise/yoga/stretching/toning; tennis/squash/racquetball; lap swimming; weight lifting/strength training; other exercise.
Ever diagnosed with high blood pressure or ever use of anti-hypertensive medication
Ever diagnosed with diabetes or current use of anti-diabetic medication.