The association of frailty with chronic kidney disease in older adults using the ASPirin in reducing events in the elderly cohort

Frailty and chronic kidney disease (CKD) both increase with age and are prevalent in older adults. However, studies in older adults examining the relationship between frailty and milder impairments of kidney function are relatively sparse. We examined the cross-sectional association of baseline estimated glomerular filtration rate (eGFR), albuminuria and CKD ([eGFR 3.0 mg/mmol]) with prefrailty and frailty in the ASPirin in Reducing Events in the Elderly (ASPREE) trial cohort of healthy older participants. Univariate logistic regression models measured the unadjusted odds ratios (OR) and 95% confidence intervals (CI) for prevalent combined prefrailty and frailty (respectively defined as presence of 1-2 or 3+ of 5 modified fried criteria) for the association between CKD, eGFR, albuminuria and other potential risk factors. Multivariable models calculated OR for prefrailty-frailty adjusted for potential confounders and either CKD, (i) eGFR and albuminuria measured as either continuous variables; (ii) or categorical variables; (iii). Of 17 759 eligible participants, 6934 were classified as prefrail, 389 were frail. CKD, eGFR and albuminuria were all associated with combined prefrailty-frailty on univariate analysis. In the multivariable modelling, neither CKD (reduced eGFR and/or albuminuria), nor eGFR (either continuous or categorical variables) were associated with prefrailty-frailty. However, albuminuria, either as a continuous variable (OR [95% CI] 1.07 [1.04-1.10]; p < .001), or categorical variable (OR 1.21 [1.08-1.36]; p = .001) was consistently associated with prefrailty-frailty. The complex relationship between albuminuria (which may be a biomarker for vascular inflammation), ageing, progressive CKD and frailty requires further investigation.