Table 2.
Baseline characteristics of Women’s Health Initiative (WHI) participants, by optimism score tertiles1
| Characteristic | Optimism score tertiles
|
P trend2 | ||
|---|---|---|---|---|
| 1: 6–22 (n = 57,998) | 2: 23–25 (n = 55,557) | 3: 26–30 (n = 39,435) | ||
| Age (y), mean ± SD | 63.3 ± 7.3 | 63.3 ± 7.1 | 62.8 ± 7.1 | < 0.001 |
| Waist circumference (cm), mean ± SD | 87.6 ± 14.3 | 86.1 ± 13.6 | 85.2 ± 13.4 | < 0.001 |
| BMI (kg/m2), mean ± SD | 28.4 ± 6.2 | 27.8 ± 5.8 | 27.5 ± 5.7 | < 0.001 |
| Energy intake (kcal), mean ± SD | 1644 ± 673 | 1641 ± 624 | 1649 ± 623 | 0.310 |
| Physical activity (MET-hr/wk), mean ±SD | 11.1 ± 13.1 | 12.7 ± 13.6 | 14.2 ± 14.6 | < 0.001 |
| Race/ethnicity, % | < 0.001 | |||
| American Indian or Alaskan Native | 0.54 | 0.33 | 0.35 | |
| Asian or Pacific Islander | 3.61 | 2.18 | 1.44 | |
| Black or African American | 8.88 | 7.64 | 8.49 | |
| Hispanic/Latina | 5.21 | 2.82 | 2.49 | |
| Non-Hispanic white | 80.4 | 86.0 | 86.4 | |
| Other | 1.35 | 1.00 | 0.89 | |
| Education, % | < 0.001 | |||
| ≤ High school diploma | 29.3 | 19.8 | 13.9 | |
| Any post-secondary education | 38.5 | 38.8 | 35.7 | |
| ≥ College graduate | 32.2 | 41.3 | 50.4 | |
| Marital status, % | < 0.001 | |||
| Never married | 4.79 | 4.25 | 4.12 | |
| Divorced or separated | 16.8 | 14.6 | 16.0 | |
| Widowed | 18.8 | 16.4 | 15.0 | |
| Married | 58.1 | 63.2 | 63.1 | |
| Marriage-like relationship | 1.59 | 1.57 | 1.83 | |
| Family income, % | < 0.001 | |||
| < $20,000 | 22.2 | 13.5 | 10.7 | |
| $20,000 to < $35,000 | 26.8 | 24.1 | 20.9 | |
| $35,000 to < $50,000 | 19.7 | 21.8 | 20.4 | |
| $50,000 to < $75,000 | 17.5 | 21.0 | 22.7 | |
| ≥ $75,000 | 13.8 | 19.6 | 25.3 | |
| Smoking, % | < 0.001 | |||
| Never | 50.2 | 50.6 | 51.9 | |
| Past | 41.4 | 43.2 | 42.3 | |
| Current | 8.35 | 6.17 | 5.79 | |
| Religious service/church attendance, % | < 0.001 | |||
| Not at all in the past month | 35.9 | 32.3 | 32.5 | |
| Once in the past month | 9.48 | 8.82 | 8.75 | |
| 2–3 times in the past month | 12.5 | 12.4 | 11.9 | |
| Once a week | 29.5 | 31.1 | 30.0 | |
| 2–6 times a week | 11.6 | 14.2 | 15.5 | |
| Every day | 1.10 | 1.22 | 1.42 | |
| History of diabetes mellitus treatment, % | 5.57 | 3.74 | 3.12 | < 0.001 |
| Hormone therapy use, % | < 0.001 | |||
| Never | 34.7 | 32.4 | 31.6 | |
| Past | 24.5 | 22.7 | 21.7 | |
| Current | 40.7 | 44.9 | 46.8 | |
| Hypertension, % | < 0.001 | |||
| Never hypertensive | 62.9 | 66.7 | 70.6 | |
| Currently untreated hypertensive | 9.02 | 7.72 | 7.24 | |
| Currently treated hypertensive | 28.0 | 25.5 | 22.1 | |
| High cholesterol requiring pills, % | 15.5 | 13.6 | 12.0 | < 0.001 |
| Depression score (short CES-D/DIS) | < 0.001 | |||
| Low (< 0.009) | 63.6 | 79.7 | 85.3 | |
| Medium (0.009–0.06) | 17.3 | 13.2 | 10.7 | |
| High (> 0.06) | 19.2 | 7.07 | 3.98 | |
Tertile 1 represents the least-optimistic scores, whereas tertile 3 represents the most-optimistic scores
P values calculated from linear (continuous variables), logistic (binary variables), or multinomial logistic (categorical variables) regression models with the variable of interest as a function of optimism tertile
The proportion of missing data for each baseline characteristic was as follows: age (0%), waist circumference (0.4%), BMI (0.9%), energy intake (0%), physical activity (4.6%), race/ethnicity (0.2%), education (0.7%), marital status (0.4%), family income (6.4%), smoking (1.1%), religious service/church attendance (0.2%), history of diabetes mellitus treatment (0.1%), hormone therapy use (2.9%), hypertension (5.4%), and high cholesterol requiring pills (5.8%), depression score (2.3%).