Depression partially mediates the association between frailty and lower urinary tract symptoms in men: cross-sectional analyses of two large population-based studies.

BACKGROUND

Clinical observations indicate a correlation between frailty and lower urinary tract symptoms (LUTS) in men. We further investigated this relationship via data from two extensive population-based studies.

METHODS

We performed a cross-sectional study via the National Health and Nutrition Examination Survey (NHANES) and the China Health and Retirement Longitudinal Study (CHARLS). Participants lacking exposure variables, outcome variables, and important covariates were not included. The frailty index (FI) was used to evaluate frailty. In CHARLS, LUTS is defined as a previous diagnosis of benign prostatic hyperplasia. In NHANES, the presence of LUTS was defined as 2 or more symptoms, including hesitancy, incomplete emptying and/or nocturia. After taking into account the covariates (demography, chronic diseases, and unhealthy lifestyles), multivariable logistic regression was employed to examine the association between frailty and LUTS. Furthermore, subgroup analysis was conducted to investigate the influence of covariables on the association between frailty and LUTS. The mediating role of depression was ultimately examined.

RESULTS

Finally, our study included 1735 participants from NHANES and 5008 participants from CHARLS. The NHANES findings indicated a positive connection between frailty and LUTS [OR 1.97, 95% CI (1.53, 2.55)] after controlling for all the variables. The link persisted when FI was set as a categorical variable [Q3, 1.78 (1.05, 3.02); Q4, 2.95 (1.76, 4.93)]. The CHARLS findings indicated a positive connection between frailty and LUTS [1.64 (1.21, 2.23)] after controlling for all variables. The connection persisted when FI was designated as a categorical variable [Q2, 1.73 (1.31, 2.28); Q3, 2.15 (1.64, 2.83); Q4, 3.11 (2.36, 4.09)]. Depression partly mediated the relationship between frailty and LUTS (18.20% in NHANES; 19.63% in CHARLS).

CONCLUSIONS

A high FI was correlated with a greater risk of LUTS in both the US and Chinese men. The relationship between frailty and LUTS was partly explained by depression.