Table 2.
Age- and multivariate-adjusted race/ethnicity-stratified hazard ratios of late-life depression incidence among 29,771 older women in the Nurses’ Health Study, 2000-2012
| Age-adjusted model a | Multivariate-adjusted model a, b | |||||
|---|---|---|---|---|---|---|
| White | Black | White | Black | Interaction | ||
| HR (95% CI) | HR (95% CI) | HR (95% CI) | HR (95% CI) | p-value c | ||
| #cases/person-years | 6,807/338,807 | 52/3,253 | 6,807/338,807 | 52/3,253 | ||
| Crude incidence rate (per 1000 person-years) | 20.1 | 16.0 | 20.1 | 16.0 | ||
| Demographic Factors | ||||||
| RN or associate degree | 1.09 (1.03-1.15) | 1.19 (0.65-2.17) | 1.01 (0.96-1.07) | 1.22 (0.62-2.40) | 0.13 | 0.718 |
| Living alone | 0.94 (0.88-0.99) | 0.59 (0.29-1.19) | 0.90 (0.84-0.96) | 0.91 (0.39-2.11) | 1.71 | 0.191 |
| Lower census-tract household income (<40K per year) | 0.97 (0.90-1.05) | 0.94 (0.50-1.78) | 0.92 (0.85-0.99) | 0.87 (0.42-1.82) | 1.25 | 0.264 |
| Born in South | 1.13 (1.03-1.22) | 0.52 (0.27-0.98) | 1.11 (1.02-1.21) | 0.46 (0.23-0.92) | 3.66 | 0.056 |
| Psycho-social Factors | ||||||
| Social network index at bottom 3 quintiles | 1.10 (1.05-1.15) | 0.62 (0.34-1.14) | 1.10 (1.05-1.16) | 0.64 (0.32-1.30) | 1.50 | 0.222 |
| Subjective social status at bottom 5 ladders | 1.31 (1.21-1.41) | 1.25 (0.57-2.74) | 1.17 (1.08-1.26) | 1.17 (0.49-2.81) | 0.0003 | 0.961 |
| No caregiving to children or grandchildren | 1.03 (0.97-1.08) | 0.87 (0.47-1.62) | 1.07 (1.02-1.13) | 0.72 (0.36-1.47) | 0.74 | 0.391 |
| Any caregiving to ill relatives | 1.22 (1.15-1.28) | 1.22 (0.63-2.35) | 1.22 (1.15-1.29) | 1.10 (0.52-2.32) | 0.04 | 0.834 |
| Lifestyle/Behavioral Factors | ||||||
| Current smoking | 1.24 (1.12-1.36) | 3.30 (1.22-8.91) | 1.17 (1.06-1.29) | 2.38 (0.80-7.08) | 3.49 | 0.062 |
| Lack of regular physical activity (<1 hour/week) | 1.40 (1.33-1.47) | 1.84 (0.94-3.59) | 1.20 (1.14-1.27) | 1.49 (0.69-3.20) | 0.40 | 0.530 |
| Heavy/binge drinking (largest number ≥ 3 drinks/day) | 1.10 (1.02-1.18) | 0.39 (0.05-3.00) | 1.12 (1.04-1.21) | 0.39 (0.05-3.26) | 0.83 | 0.362 |
| Health/Medical Factors | ||||||
| Obesity (body mass index ≥ 30 kg/m2) | 1.19 (1.12-1.26) | 1.14 (0.62-2.12) | 0.97 (0.91-1.03) | 0.92 (0.43-1.96) | 0.09 | 0.763 |
| Medical comorbidity (≥2 chronic conditions) | 1.62 (1.51-1.73) | 0.30 (0.07-1.28) | 1.40 (1.30-1.50) | 0.26 (0.06-1.19) | 5.15 | 0.024 |
| Difficulty falling or staying asleep | 1.76 (1.68-1.85) | 2.11 (1.16-3.82) | 1.62 (1.54-1.70) | 1.71 (0.90-3.28) | 0.40 | 0.528 |
| Excessive sleep (≥9 hours/day) | 1.27 (1.17-1.37) | 0.44 (0.10-1.96) | 1.25 (1.15-1.36) | 0.38 (0.08-1.88) | 0.97 | 0.324 |
| Significant physical or functional limitation | 1.75 (1.66-1.85) | 2.79 (1.32-5.87) | 1.39 (1.31-1.48) | 1.93 (0.82-4.56) | 1.82 | 0.178 |
| Bodily pain (moderate or worse) | 1.77 (1.68-1.86) | 2.38 (1.30-4.38) | 1.42 (1.35-1.50) | 1.57 (0.77-3.19) | 2.27 | 0.132 |
a
The hazard ratios and 95% confidence intervals are stratum-specific by race. Individual with a risk factor are compared to individuals without that risk factor, within each race/ethnic group.
b
Multivariate-adjusted model adjusted for all covariates listed in the table simultaneously
c
p for interaction was calculated using a Wald χ2 test with 1 degree of freedom from the multivariate-adjusted model