Association between frailty status and risk of chronic lung disease: an analysis based on two national prospective cohorts

Background

The association between the frailty index (FI) and the risk of chronic lung diseases (CLDs) remains unexplored, warranting further research.

Methods and materials

This study investigated the relationship between FI and CLD risk using data from the China Health and Retirement Longitudinal Study (CHARLS) and English Longitudinal Study of Ageing (ELSA), comprising a combined sample of 9642 individuals. Propensity score weighting was used to ensure similar distribution of covariates across FI groups. The Wilcoxon rank-sum test was used to analyze differences in FI scores between groups with and without CLD. Kaplan–Meier curves and Cox regression analysis were employed to explore the association between frailty status and CLD incidence, with sensitivity analyses conducted for validation.

Results

Higher FI scores were significantly associated with increased CLD risk in both cohorts (p < .05). Kaplan–Meier survival and Cox regression analyses indicated that frail individuals have a significantly elevated risk of CLD compared to robust individuals, particularly in certain subgroups (e.g., female) within the CHARLS cohort (p < .05). The ELSA cohort yielded similar results (p < .05), affirming FI as a strong predictor of CLD. Additional risk factors identified included age, smoking, and unmarried status (p < .05). Frail individuals consistently exhibited the highest risk in both cohorts (CHARLS HR = 1.54, p = .003; ELSA HR = 6.64, p < .001). The sensitivity analysis did not substantially alter the significant associations.

Conclusion

These findings emphasize the critical role of frailty in the development of CLD, suggesting that targeted interventions could reduce CLD risk.