What is the clinical evidence from this study?

Study design: Observational. Population: Frailty (n=6104). Intervention: Dietary index for gut microbiota (DI-GM) vs. Lowest DI-GM quintile. Primary outcome: Risk of frailty (OR 0.68, 95% CI 0.54-0.86, p=0.001).

December 5, 2025Journal of Translational Medicine1 citationsOpen Access

Associations of dietary intake for gut microbiota with frailty risk and mortality in older adults

DGDa GanNanchang University YSYuyang ShiNanchang University YZYunya ZhuFirst Affiliated Hospital of Gannan Medical University

Key Result

Older adults in the highest quintile of the dietary index for gut microbiota had a 32% reduced risk of frailty compared to those in the lowest quintile (OR 0.68).

Study Design

Type

Observational (n=6,104)

Structured PICO

Does a higher dietary index for gut microbiota reduce the risk of frailty and mortality in older adults?

Population

6,104 adults aged 65 and older from the US NHANES cohort were evaluated to determine the association between a dietary index for gut microbiota and the risk of frailty.

Exposure

Highest quintile of Dietary Index for Gut Microbiota (DI-GM) score, calculated based on the intake of 13 dietary components associated with a favorable gut microbiota profile.

Comparator

Lowest quintile of Dietary Index for Gut Microbiota (DI-GM) score.

Outcome

Risk of frailty (cross-sectional) and all-cause mortality, cardiovascular disease (CVD) mortality, and cancer mortality in frail participants over a median 5.3 years follow-up.hard clinical

A diet promoting a healthy gut microbiota is associated with a lower risk of frailty in older adults and reduced all-cause and cardiovascular mortality among those who are already frail.

Main Result

Odds Ratio: 0.68 (95% CI 0.54–0.86)

p-value: p=0.001

Limitations

Observational design cannot establish causality or rule out unmeasured confounders
Potential reverse causality as frail individuals may consume less food
Self-reported dietary data and covariates are subject to recall and social desirability biases
DI-GM may not include all relevant dietary components associated with gut microbiota
Frailty index definition relied on questionnaire surveys
Lack of direct high-throughput sequencing to validate gut microbiota taxa or metabolites

Abstract

OBJECTIVE: The associations between a diet that associated with a healthy gut microbiota and the risk of frailty, as well as mortality in older adults with frailty, remains unclear. Therefore, this study aimed to examine the associations of dietary index for gut microbiota (DI-GM) with frailty risk, as well as the all-cause mortality and cause-specific mortality in frail participants. METHODS: A total of 6,104 participants aged 65 and older from six cycles of the National Health and Nutrition Examination Survey (2007–2018) were included in this study. DI-GM was calculated based on the intake of 13 dietary components, with a higher score reflecting a diet that associated with a more favorable gut microbiota profile. Frailty was assessed using the 48-item frailty index, and participants with a frailty index exceeding 0.21 were classified as having frailty. Mortality status and cause of death were determined through linkage to the National Death Index records until December 31, 2019. Weighted multivariable logistic regression was conducted to investigate the associations between DI-GM and the risk of frailty. Weighted multivariable Cox proportional hazards regression models were used to examine the associations of DI-GM with all-cause mortality, cardiovascular disease (CVD) mortality, and cancer mortality in frail participants. RESULTS: Compared with participants in the lowest DI-GM quintile, those in the highest quintile were associated with a 32% (95% confidence interval CI: 14% to 46%) reduced risk of frailty. Over a median 5.3 years follow-up, 778 deaths occurred among participants with frailty, including 258 deaths due to cardiovascular disease and 139 deaths due to cancer. The hazard ratios and 95% CI for all-cause mortality, CVD mortality, and cancer mortality were 0.73 (0.57, 0.93), 0.59 (0.36, 0.97), and 1.41 (0.76, 2.62), respectively, when comparing the extreme DI-GM quintiles. CONCLUSION: DI-GM was inversely associated with the risk of frailty in older adults. Additionally, a higher DI-GM was associated with a reduced risk of all-cause mortality and CVD mortality in individuals with frailty. Diet linked to a healthy gut microbiota might be associated with a reduced risk of frailty in older adults and a decreased risk of premature mortality in individuals with frailty.

问 AI

Bookmark

View Full Paper