Association between changes of frailty status/frailty components status and rapid loss of kidney function in middle-...

Frailty and its components are proposed to associate with kidney function, but little attention is paid to the significance of changes in their status on rapid loss of kidney function. This study aimed to investigate the association between changes in frailty and its components status with rapid loss of renal function.

This study used data from China Health and Retirement Longitudinal Study (CHARLS). Frailty status was measured using the Fried frailty phenotype (FP) scale, including five components: slowness, weakness, exhaustion, inactivity, and shrinking. Frailty status was further classified into three levels: robust (0 component), prefrail (1-2 components) and frail (3-5 components). Changes in frailty status were assessed by frailty status at baseline and 4- year follow-up. Rapid loss of kidney function was defined as a rate of estimate glomerular filtration rate(eGFR) decline ≥ 4 ml/min per 1.73 m²per year. Logistic regression models were performed to assess the association between changes in frailty status and its components status with rapid eGFR decline.

A total of 2705 participants were included with 316 (11.68%) participants categorized as rapid eGFR decline during the 4-year follow-up. Compared with baseline prefrail participants who progressed to frail, prefrail participants who maintained prefrail or recovered to robust status had decreased risks of rapid eGFR decline (stable prefrail status, OR = 0.608, 95% CI: 0.396-0.953; recover to robust, OR = 0.476, 95% CI: 0.266-0.846). In contrast, among baseline robust or frail participants, we did not find changes in frailty status significantly affect the risks of rapid loss of kidney function. Moreover, participants who experienced incident weakness showed the significant relationship with an increased risk of rapid eGFR decline (OR = 1.531, 95% CI: 1.051-2.198) compared to stable non-weakness participants. Other changes of frailty components status did not significantly affect the risks of rapid eGFR decline.

The progression of frailty status increases the risks of rapid eGFR decline among prefrail populations. Preventing weakness, may benefit kidney function.