Frailty and frailty progression in relation to the risk of benign prostatic hyperplasia/lower urinary tract symptoms among Chinese middle-aged and older men: a prospective cohort study.

Abstract

Background: Frailty and benign prostatic hyperplasia/lower urinary tract symptoms (BPH/LUTS) are age-related conditions, but their longitudinal relationship remains unclear. This study investigated associations between frailty index (FI) trajectories, baseline frailty status, and incident BPH/LUTS in Chinese middle-aged and older men.

Methods: Data from three waves (2011-2015) of the China Health and Retirement Longitudinal Study (CHARLS) were analyzed. Group-based trajectory modeling identified FI trajectories. Multivariable logistic regression examined associations of baseline frailty status (robust, prefrail, frail) and FI trajectories with incident BPH/LUTS. Incremental predictive value of trajectories beyond baseline status was quantified using net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

Results: Among 4,449 men, four distinct FI trajectories were identified. Compared to the Persistently Low trajectory, Moderately Increasing and High-Increasing trajectories showed significantly higher BPH/LUTS risk (ORs: 2.01 [1.38-2.99] and 2.82 [1.79-4.45]; p-trend < 0.001). Baseline prefrail and frail status were also associated with elevated risk (ORs: 1.47 [1.13-1.90] and 1.67 [1.10-2.49], respectively). Dynamic frailty trajectories demonstrated improved risk reclassification over baseline assessment alone (continuous NRI: 0.284, p < 0.001; IDI: 0.011, p = 0.001).

Conclusions: Both baseline frailty status and dynamic FI trajectories were independently associated with BPH/LUTS risk. Longitudinal trajectories exhibited stronger associations and greater predictive value, highlighting the importance of monitoring frailty progression for improved risk stratification and targeted prevention.