Diet quality and frailty among older adults with chronic kidney disease

Frailty is common among older adults with chronic kidney disease (CKD), but its association with overall diet quality remains insufficiently characterized. We examined associations of the Healthy Eating Index-2015 (HEI-2015) total and component scores with frailty and explored variation across clinically relevant subgroups. This cross-sectional study included adults aged 60 years or older with CKD from the 2005–2018 National Health and Nutrition Examination Survey. HEI-2015 scores were calculated from two 24-hour dietary recalls, and frailty was defined using a 49-item frailty index. Survey-weighted logistic regression and restricted cubic spline models were fitted. Component and subgroup analyses were exploratory; multiple imputation was used in a sensitivity analysis. Among 2,409 participants, representing approximately 12.0 million older U.S. adults with CKD, 1,059 were frail (weighted prevalence, 39.44%). In the primary adjusted model ( n = 2,159), each 10-point increase in HEI-2015 score was associated with lower odds of frailty (OR, 0.85; 95% CI, 0.76–0.94; P = 0.003). The highest versus lowest quartile had an OR of 0.56 (95% CI, 0.39–0.81; P = 0.002; P for trend = 0.007). In exploratory component analyses, each 1-point increase in the whole-grains score (OR, 0.96; 95% CI, 0.93–1.00), seafood and plant proteins score (OR, 0.93; 95% CI, 0.87–0.98), and sodium score, reflecting lower sodium intake per unit of energy (OR, 0.95; 95% CI, 0.91–0.99), was associated with lower odds of frailty. Restricted cubic spline analysis supported an inverse association without evidence of nonlinearity (P for overall = 0.004; P for nonlinearity = 0.266). The association differed by age (P for interaction = 0.005) but not by sex or CKD stage. Multiple-imputation analyses supported the overall inverse association. Higher HEI-2015 scores were associated with lower odds of frailty among older adults with CKD. Diet quality may complement assessment of energy and protein intake and individualized nutrient management. Prospective studies are needed to clarify temporality and validate the exploratory findings.