Alternative Healthy Eating Index and mortality over 18 y of follow-up: results from the Whitehall II cohort

Abstract

Background: Indexes of diet quality have been shown to be associated with decreased risk of mortality in several countries. It remains unclear if the Alternative Healthy Eating Index (AHEI), designed to provide dietary guidelines to combat major chronic diseases, is related to mortality risk.

Objective: We aimed to examine the association between adherence to the AHEI and cause-specific mortality over 18 y of follow-up in a British working population.

Design: Analyses are based on 7319 participants (mean age: 49.5 y; range: 39-63 y; 30.3% women) from the Whitehall II Study. Cox proportional hazards regression models were performed to analyze associations of the AHEI (scored on the basis of intake of 9 components: vegetables, fruit, nuts and soy, white or red meat, trans fat, polyunsaturated or saturated fat, fiber, multivitamin use, and alcohol) with mortality risk.

Results: After potential confounders were controlled for, participants in the top compared with the bottom third of the AHEI score showed 25% lower all-cause mortality [hazard ratio (HR): 0.76; 95% CI: 0.61, 0.95] and >40% lower mortality from cardiovascular disease (CVD; HR: 0.58; 95% CI: 0.37, 0.91). Consumption of nuts and soy and moderate alcohol intake appeared to be the most important independent contributors to decreased mortality risk. The AHEI was not associated with cancer mortality or noncancer/non-CVD mortality.

Conclusion: Our findings suggest that the encouragement of adherence to the AHEI dietary recommendations constitutes a valid and clear public health recommendation that would decrease the risk of premature death from CVD.

FIGURE 1.

Survival distribution over 18 y of follow-up as a function of Alternative Healthy Eating Index (AHEI) tertiles (tert) for the 7319 Whitehall II participants. Tertile 1—mean ± SD: 36.5 ± 6.3; median (range): 37.5 (13.5−44.5). Tertile 2—mean ± SD: 50.6 ± 3.1; median (range): 50.5 (45.5−55.5). Tertile 3—mean ± SD: 63.3 ± 5.3; median (range): 62.5 (56.5−85.5). Survival curves were generated with the use of actuarial life table methods with Wilcoxon tests to compare survival between AHEI tertile groups. S(t), survival function.

FIGURE 2.

Associations between Alternative Healthy Eating Index (AHEI) tertiles (T) and all-cause and cause-specific mortality over 18 y of follow-up for the 7319 Whitehall II participants. Cox proportional hazards models were adjusted for sex, age, ethnic group, marital status, occupational grade, smoking habits, total energy intake, physical activity, BMI categories, concentrations of inflammatory markers (C-reactive protein and interleukin-6) categorized in tertiles, metabolic syndrome status, prevalence of cardiovascular disease (CVD), dyslipidemia, hypertension, and prevalence of type 2 diabetes status at baseline. For 7 participants, data on cause of death were missing.