Association between sarcopenia and frailty in elderly patients with chronic kidney disease

Frailty and sarcopenia are prevalent in chronic kidney disease (CKD) populations and could increase the risk for adverse health outcomes. Few studies assess the correlation between frailty, sarcopenia and CKD in non-dialysis patients. Therefore, this study aimed to determine frailty-associated factors in elderly CKD stage I-IV patients, expected to early identify and intervene in the frailty of elderly CKD patients.

A total of 774 elderly CKD I-IV patients (>60 years of age) recruited from 29 clinical centers in China between March 2017 and September 2019 were included in this study. We established a Frailty Index (FI) model to evaluate frailty risk and verified the distributional property of FI in the study population. Sarcopenia was defined according to the criteria of the Asian Working Group for Sarcopenia 2019. Multinomial logistic regression analysis was used to assess the associated factors for frailty.

Seven hundred seventy-four patients (median age 67 years, 66.0% males) were included in this analysis, with a median estimated glomerular filtration rate of 52.8 mL/min/1.73 m² . The prevalence of sarcopenia was 30.6%. The FI exhibited a right-skewed distribution. The age-related slope of FI was 1.4% per year on a logarithmic scale (r²  = 0.706, 95% CI 0.9, 1.8, P < 0.001). The upper limit of FI was around 0.43. The FI was related to mortality (HR = 1.06, 95% CI 1.00, 1.12, P = 0.041). Multivariate multinomial logistic regression analysis showed that sarcopenia, advanced age, CKD stage II-IV, low level of serum albumin and increased waist-hip ratio were significantly associated with high FI status, while advanced age and CKD stage III-IV were significantly associated with for median FI status. Moreover, the results from the subgroup were consistent with the leading results.

Sarcopenia was independently associated with an increased risk for frailty in elderly CKD I-IV patients. Patients with sarcopenia, advanced age, high CKD stage, high waist-hip ratio and low serum albumin level should be assessed for frailty.