Background: Cross-sectional studies suggest an association between functional status and chronic kidney disease (CKD). Whether physical function deteriorates with progression of CKD is unknown.
Methods: To determine associations among CKD, physical function, and sexual function in women, we conducted cross-sectional and longitudinal analyses of 2,761 women enrolled in the Heart and Estrogen/Progestin Replacement Study. Physical and sexual function were evaluated using the Duke Activity Status Index (DASI) and the Sexual Problems Scale of the Medical Outcomes Study, respectively. Glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease regression equation. In addition to analyses across the spectrum of GFR, CKD was categorized as mild (estimated GFR, 45 to 60 mL/min/1.73 m2), moderate (estimated GFR, 30 to 44 mL/min/1.73 m2), and severe (estimated GFR, <30 mL/min/1.73 m2) according to a modification of recently established classification guidelines.
Results: Mean age of study participants was 67 +/- 7 years, and mean estimated GFR was 61 +/- 14 mL/min/1.73 m2. In unadjusted analyses, mean baseline DASI score was 10 points lower in women with an estimated GFR less than 30 mL/min/1.73 m2 than in women with an estimated GFR of 60 mL/min/1.73 m2 or greater (P < 0.0001). Estimated GFR remained significantly associated with DASI score after multivariable adjustment. In longitudinal analyses, a decline in estimated GFR was associated with a significant decline in DASI score independent of baseline estimated GFR and other factors. There were no significant associations between estimated GFR and psychosocial aspects of sexual function.
Conclusion: CKD is associated with impaired physical function, and a decline in estimated GFR is associated with a decline in physical function.