Impact of Chinese visceral adiposity index on all-cause mortality risk in community-dwelling older adults: a prospective cohort study.

BACKGROUNDS

Whether excess visceral fat tissue increases the risk of death in older individuals remains controversial.

AIMS

To investigate the association between the Chinese Visceral Adiposity Index (CVAI) and all-cause mortality risk in older Chinese individuals.

METHODS

This cohort study utilized data of individuals aged ≥ 65 years in 2014 to 2018 wave from the Chinese Longitudinal Healthy Longevity Survey database. Older individuals in the 2014 wave were included and followed up in 2018. CVAI was calculated based on age, body size, and blood lipid parameters, with higher values indicating increased visceral fat. Survival status was determined from official death certificates, local primary healthcare providers, or the family members of participants. Kaplan-Meier survival curve and log-rank test were employed to analyze cumulative mortality risk through CVAI tertiles (tertile 1: CVAI index < 97.34; tertile 2: 97.43 ≤ CVAI index < 132.21; and tertile 3: CVAI index ≥ 132.21). A Cox proportional hazards regression model was used to assess the relationship between the CVAI groups and all-cause mortality risk. Additionally, a sensitivity analysis was performed by excluding participants who died within the first year of follow-up. A subgroup analysis was performed based on age and sex, and a restricted cubic spline plot was created to analyze the dose-response relationship between CVAI and mortality risk.

RESULTS

A total of 1414 individuals were included, and the mean age of the participants was 84.6 (standard deviation: 10.9) years, of which 46.4% were women and 32.8% were died during a median follow-up time of 36.4 months. In the multivariable adjusted Cox regression model, we observed a significantly lower risk of mortality in the CVAI tertile 2 and 3 groups than in the tertile 1 group. The hazard ratios (HR) of the tertile 2 and 3 groups were 0.68 (95% CI, approximately 0.52-0.89) and 0.63 (95% CI, approximately 0.48-0.82), respectively. Subgroup analysis revealed that the protective effect of higher CVAI levels on mortality was more pronounced in participants aged 65-79 years and in women.

CONCLUSION

Our study established a linear relationship between CVAI and mortality risk among community-dwelling older adults, with higher CVAI levels associated with a lower risk of all-cause mortality. These findings highlight the potential importance of visceral adiposity in predicting mortality risk in community-dwelling older adults.