TABLE 5.
Mean differences in slopes of cognitive decline over 3 cognitive interviews by quintiles of dietary ferric-reducing antioxidant power (FRAP) scores1
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | P for trend2 | |
| n | 3202 | 3202 | 3202 | 3202 | 3202 | |
| FRAP score (mmol/d)3 | 7.5 (6.3–8.5) | 9.9 (9.2–10.6) | 11.5 (10.2–12.2) | 12.8 (10.7–14.1) | 12.9 (10.8–15.6) | |
| TICS | ||||||
| Model 14 | 0.005 | 0.04 (0.00, 0.08)6 | 0.03 (−0.01, 0.07) | 0.03 (−0.01, 0.07) | 0.03 (−0.01, 0.07) | 0.3 |
| Model 27 | 0.00 | 0.03 (−0.01, 0.07) | 0.03 (−0.01, 0.07) | 0.02 (−0.02, 0.06) | 0.02 (−0.02, 0.06) | 0.6 |
| Global | ||||||
| Model 14 | 0.00 | 0.01 (0.00, 0.01) | 0.00 (0.00, 0.01) | 0.00 (−0.01, 0.01) | 0.01 (0.00, 0.01) | 0.3 |
| Model 27 | 0.00 | 0.00 (0.00, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (0.00, 0.01) | 0.5 |
| Verbal | ||||||
| Model 14 | 0.00 | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.8 |
| Model 27 | 0.00 | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 0.00 (−0.01, 0.01) | 1.0 |
TICS, Telephone Interview of Cognitive Status. Dietary FRAP scores were averaged from 1980 until the initial cognitive interview. Results were obtained from multivariable-adjusted mixed linear regression models that included terms for continuous time, exposure, and covariates and interaction terms for exposure and each covariate with continuous time.
Calculated in separate multivariable-adjusted mixed linear regression models by using the median intake of each quintile as a continuous variable.
All values are medians; interquartile ranges in parentheses.
Adjusted for age (continuous) and education (registered nurse, bachelor's degree, and graduate degree).
Mean difference (all such values); reference.
Mean difference; 95% CI in parentheses (all such values).
Adjusted for age, education, antidepressant use (yes or no), smoking (never, former, or current), physical activity (in quintiles, missing), BMI (in kg/m2; <22, 22–24, 25–29, ≥30, or missing), vitamin E supplement use (yes, no, or missing), vitamin C supplement use (yes, regular; yes, seasonal; no; or missing), multivitamin supplement use (yes, no, or missing), high blood pressure (yes or no), myocardial infarction (yes or no), and type 2 diabetes (yes or no).