title: Association between body composition and frailty among prevalent hemodialysis patients: a US Renal Data System special study.
abstract: Studies of frailty among patients on hemodialysis have relied on definitions that substitute self-reported functioning for measures of physical performance and omit weight loss or substitute alternate criteria. We examined the association between body composition and a definition of frailty that includes measured physical performance and weight loss in a cross-sectional analysis of 638 adult patients receiving maintenance hemodialysis at 14 centers. Frailty was defined as having three of following characteristics: weight loss, weakness, exhaustion, low physical activity, and slow gait speed. We performed logistic regression with body mass index (BMI) and bioelectrical impedance spectroscopy (BIS)-derived estimates of intracellular water (ICW), fat mass, and extracellular water (ECW) as the main predictors, and age, sex, race, and comorbidity as covariates. Overall, 30% of participants were frail. Older age (odds ratio [OR], 1.31 per 10 years; 95% confidence interval [95% CI], 1.14 to 1.50), diabetes (OR, 1.65; 95% CI, 1.13 to 2.40), higher fat mass (OR, 1.18; 95% CI, 1.02 to 1.37), and higher ECW (OR, 1.33; 95% CI, 1.20 to 1.47) associated with higher odds of frailty. Higher ICW associated with lower odds of frailty (OR, 0.80 per kg; 95% CI, 0.73 to 0.87). The addition of BMI data did not change the area under the receiver operating characteristics curve (AUC; AUC=0.66 versus 0.66; P=0.71), but the addition of BIS data did change the AUC (AUC=0.72; P<0.001). Thus, individual components of body composition but not BMI associate strongly with frailty in this cohort of patients receiving hemodialysis.
authors.affiliation: Department of Medicine, Division of Nephrology and.
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Johansen
authors.forename: Lorien S
authors.initials: LS
authors.lastname: Dalrymple
authors.forename: Cynthia
authors.initials: C
authors.lastname: Delgado
authors.forename: George A
authors.initials: GA
authors.lastname: Kaysen
authors.forename: John
authors.initials: J
authors.lastname: Kornak
authors.forename: Barbara
authors.initials: B
authors.lastname: Grimes
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Chertow
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001823:Body Composition; D001834:Body Water; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000453:epidemiology; D017097:Electric Impedance; D005221:Fatigue / Q000453:epidemiology; D005260:Female; D016330:Frail Elderly / Q000706:statistics & numerical data*; D005684:Gait; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D018908:Muscle Weakness / Q000453:epidemiology; D016017:Odds Ratio; D010807:Physical Endurance; D012372:ROC Curve; D006435:Renal Dialysis / Q000706:statistics & numerical data*; D012737:Sex Factors; D014481:United States / Q000453:epidemiology; D015431:Weight Loss