Dietary Patterns, Metabolic Risk and Survival in Older Adults

Abstract

Background: Recent evidence suggests that older adults' diets can appreciably impact their health. Dietary patterns may better capture the multifaceted effects of diet on health than individual nutrients or foods.

Objectives: The purpose of this study was to identify the dietary patterns of a cohort of older adults, and examine relationships with body composition, insulin sensitivity, systemic inflammation, and survival. The influence of a polymorphism in the peroxisome proliferator-activated receptor-γ (PPAR-γ) gene was considered.

Design: The Health, Aging and Body Composition (Health ABC) Study is a prospective cohort study of 3075 older adults. Participants' body composition, genetic variation, glucose metabolism, systemic inflammation, and vital status were evaluated in detail. Food intake was assessed with a modified Block food frequency questionnaire (FFQ), and dietary patterns were derived by cluster analysis.

Results: Six clusters were identified, including a 'Healthy foods' cluster characterized by higher intake of lowfat dairy products, fruit, whole grains, poultry, fish and vegetables. An interaction was found between dietary pattern and PPAR-γ Pro12Ala genotype in relation to body composition. While Pro homozygotes in the 'Healthy foods' cluster did not differ significantly in body composition from those in other clusters, men with the Ala allele in the 'Healthy foods' cluster had significantly lower adiposity than those in other clusters. The 'Healthy foods' cluster had lower fasting insulin and HOMA-IR values than the 'High-fat dairy products' and 'Breakfast cereal' clusters, while no differences were found in fasting or 2-hour glucose. With respect to inflammation, the 'Healthy foods' cluster had lower levels of IL-6 than the 'High-fat dairy products' and 'Sweets and desserts' clusters, and did not differ in CRP or TNF-α. The 'Healthy foods' cluster also had a lower risk of mortality than the 'High-fat dairy products' and 'Sweets and desserts' clusters, and more years of healthy life and more optimal nutritional status than the other clusters.

Conclusion: A dietary pattern consistent with current guidelines to consume relatively high amounts of vegetables, fruit, whole grains, poultry, fish and lowfat dairy products may reduce the metabolic risk and improve the nutritional status, quality of life and survival of older adults.