Table 2.
Hazard ratios (95% confidence intervals) for frailty according to quintiles of plant‐based diet indices among women aged ≥60 y in the Nurses' Health Study
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | Per 10‐unit increase | P value for trend | |
|---|---|---|---|---|---|---|---|
| Healthful plant‐based diet index (hPDI) | |||||||
| Participants, n | 18 447 | 17 131 | 16 277 | 15 677 | 14 702 | ||
| Person‐years | 234 952 | 229 290 | 236 452 | 239 952 | 235 756 | ||
| Frailty cases | 2779 | 2672 | 2687 | 2584 | 2188 | ||
| Age‐adjusted | Ref. 1.0 | 0.93 (0.89, 0.98) | 0.87 (0.83, 0.92) | 0.80 (0.75, 0.84) | 0.65 (0.61, 0.68) | 0.78 (0.75, 0.80) | <0.001 |
| Multivariable Model 1 | Ref. 1.0 | 0.94 (0.90, 1.00) | 0.88 (0.83, 0.93) | 0.81 (0.77, 0.86) | 0.70 (0.66, 0.74) | 0.81 (0.78, 0.83) | <0.001 |
| Multivariable Model 2 | Ref. 1.0 | 0.96 (0.91, 1.02) | 0.92 (0.87, 0.97) | 0.86 (0.81, 0.91) | 0.77 (0.72, 0.81) | 0.85 (0.82, 0.88) | <0.001 |
| Unhealthful plant‐based diet index (uPDI) | |||||||
| Participants, n | 17 225 | 16 705 | 16 211 | 15 978 | 16 115 | ||
| Person‐years | 239 041 | 230 904 | 238 420 | 231 686 | 236 350 | ||
| Frailty cases | 2166 | 2352 | 2628 | 2667 | 3097 | ||
| Age‐adjusted | Ref. 1.0 | 1.07 (1.01, 1.14) | 1.15 (1.09, 1.22) | 1.15 (1.09, 1.22) | 1.30 (1.23, 1.38) | 1.14 (1.11, 1.17) | <0.001 |
| Multivariable Model 1 | Ref. 1.0 | 1.10 (1.03, 1.16) | 1.20 (1.13, 1.27) | 1.21 (1.14, 1.28) | 1.39 (1.31, 1.47) | 1.18 (1.15, 1.22) | <0.001 |
| Multivariable Model 2 | Ref. 1.0 | 1.06 (1.00, 1.12) | 1.14 (1.08, 1.21) | 1.13 (1.06, 1.20) | 1.24 (1.17, 1.32) | 1.12 (1.08, 1.15) | <0.001 |
Note: The multivariable Model 1 was adjusted for age (months), calendar time (4‐year intervals), body mass index (<25.0, 25.0–29.9, and ≥30.0 kg/m2) at baseline, socio‐economic status, smoking status (never, past and current; 1–14, 15–24, and ≥25 cigarettes per day), alcohol intake (0, 1.0–4.9, 5.0–14.9 or ≥15.0 g/day), energy intake (quintiles of kcal/day), margarine intake, and medication use (aspirin, postmenopausal hormone therapy, diuretics, β‐blockers, calcium channel blockers, ACE inhibitors, other blood pressure medication, statins and other cholesterol lowering drugs, insulin, and oral hypoglycaemic medication). The multivariable Model 2 was adjusted for Model 1 + physical activity.