Dietary patterns in relation to quality-adjusted life years in the EPIC-NL cohort

Abstract

Background. Dietary patterns have been associated with the incidence or mortality of individual non-communicable diseases, but their association with disease burden has received little attention. Objective. The aim of our study was to relate dietary patterns to health expectancy using quality-adjusted life years (QALYs) as outcome parameter. Methods. Data from the EPIC-NL study were used, a prospective cohort study of 33,066 healthy men and women aged 20-70 years at recruitment A lifestyle questionnaire and a validated food frequency questionnaire were administered at study entry (1993-1997). Five dietary patterns were studied: three a priori patterns (the modified Mediterranean Diet Score (mMDS), the WHO-based Healthy Diet Indicator (HDI) and the Dutch Healthy Diet index (DHD-index)) and two a posteriori data-based patterns. QALYs were used as a summary health measure for healthy life expectancy, combining a person's life expectancy with a weight reflecting loss of quality of life associated with having chronic diseases. Results. The mean QALYs of the participants were 74.9 (standard deviation 4.4).A higher mMDS and HDI were associated with a longer life in good health. Participants who had a high mMDS score (6-9) had 0.17 [95% CI, 0.05; 030] more QALYs than participants with a low score (0-3), equivalent to two months longer life in good health. Participants with a high HDI score also had more QALYs (0.15 [95% CI, 0.03; 0.27]) than participants with a low HDI score. Conclusion. A Mediterranean-type diet and the Healthy Diet Indicator were associated with approximately 2 months longer life in good health. (C) 2015 Elsevier Inc All rights reserved.