Healthy eating and all-cause mortality among Chinese aged 80 years or older

Abstract

Abstract Background There is little evidence of the influence of dietary patterns on mortality risk among adults 80 years or older (“oldest-old”). We evaluated the association between the Simplified Healthy Eating index (SHE-index) and mortality among Chinese oldest-old. Methods Population-based cohort study from the Chinese Longitudinal Healthy Longevity Survey (CLHLS 1998–2014, n = 35 927), conducted in 22 Chinese provinces, were pooled for analysis. The first seven waves of the CLHLS (1998, 2000, 2002, 2005, 2008–09, 2011–12, and 2013–2014) were utilized, with follow-up to the last wave (2018) (range 0–21 years). The SHE-index was collected in each wave, and was constructed from intake frequency of nine dietary variables, with a higher score indicating better diet quality. Cox proportional hazards model with dietary patterns as a time-varying exposure was employed to analyze the relationship between SHE-index and mortality. Results At baseline, the median age of all participants was 92 years (25th percentile, 85 years; 75th percentile, 100 years). In multivariable models, the hazard ratios (95% confidence intervals) for SHE-index quartile 2, quartile 3 and quartile 4 versus quartile1 were 0.91 (0.88, 0.93), 0.89 (0.86, 0.92) and 0.82 (0.78, 0.85), respectively. Results were generally consistent for men and women and in a large number of sensitivity analyses. Conclusions Healthier eating patterns were associated with a significant reduction in the risk of all-cause mortality among Chinese oldest-old, lending support to the importance of life-long adherence to healthy diet into advanced old age.