TABLE 4.
Mean differences in initial cognitive function 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 | 0.10 (−0.03, 0.23)6 | 0.12 (−0.01, 0.26) | 0.16 (0.03, 0.30) | 0.11 (−0.02, 0.24) | 0.08 |
Model 27 | 0.00 | 0.06 (−0.07, 0.19) | 0.07 (−0.07, 0.20) | 0.09 (−0.04, 0.22) | 0.06 (−0.07, 0.19) | 0.3 |
Global | ||||||
Model 14 | 0.00 | 0.02 (−0.01, 0.05) | 0.03 (0.00, 0.06) | 0.05 (0.02, 0.09) | 0.04 (0.01, 0.07) | 0.002 |
Model 27 | 0.00 | 0.01 (−0.02, 0.04) | 0.01 (−0.02, 0.04) | 0.03 (0.00, 0.07) | 0.02 (−0.01, 0.06) | 0.05 |
Verbal | ||||||
Model 14 | 0.00 | 0.01 (−0.03, 0.04) | 0.02 (−0.02, 0.06) | 0.05 (0.01, 0.08) | 0.03 (−0.01, 0.06) | 0.03 |
Model 27 | 0.00 | 0.00 (−0.04, 0.04) | 0.00 (−0.03, 0.04) | 0.03 (−0.01, 0.06) | 0.01 (−0.02, 0.05) | 0.2 |
TICS, Telephone Interview of Cognitive Status. Dietary FRAP scores were averaged from 1980 until the initial cognitive interview. Results were obtained from multivariable-adjusted linear regression models.
Calculated in separate multivariable-adjusted 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).