Association of changes in plant-based diet consumption with all-cause mortality among older adults in China: a prospective study from 2008 to 2019.

ABSTRACT

OBJECTIVES: To examine the association of changes in plant-based diet consumption with all-cause mortality among older adults in China. DESIGN: Cohort study. SETTING: This cohort study of 11 years used data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), a long-term, nationwide survey covering 23 provinces in China. PARTICIPANTS: A total of 7843 older participants aged ≥60 years were included in this study. MEASUREMENTS Changes in plant-based diets consumption (2008-2011) were assessed by 3 graded plant-based diet indices, including an overall plant-based diet index (PDI), a healthful plant-based diet index (hPDI), and an unhealthful plant-based diet index (uPDI). The main outcome was all-cause mortality. Multivariable-adjusted Cox proportional-hazards models were fitted to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) of mortality for changes in PDI, hPDI, and uPDI. RESULTS: A total of 7843 participants (mean [SD] age, 82.2 [10.9] years; 3588 [45.7%] men) were included in this study. During a median (IQR) of 9 (5-10) years of follow-up, 3749 deaths were documented. Compared with older adults whose plant-based diet indices were relatively stable, older adults with the greatest decrease (quintile 1) in PDI, hPDI, and uPDI had respectively 32% (95% CI, 19%-47%) higher, 21% (95% CI, 9%-33%) higher, and 10% (95% CI, 4%-21%) lower risk of death. Compared with older adults whose diet indices were relatively stable, older adults with the greatest increase (quintile 5) in uPDI had a 13% higher risk of death (95% CI, 1%-21%), while no significant associations of the increased PDI and hPDI with all-cause mortality were observed. CONCLUSION: Maintaining the consumption of overall and healthful plant-based diets, and decreasing the consumption of an unhealthful plant-based diet can be beneficial in preventing or delaying premature death among Chinese older adults.