Nutritional Status is Associated With Preserved Kidney Function in Patients With Autosomal Dominant Polycystic Kidney Disease

Objective: Malnutrition is a common complication in autosomal dominant polycystic kidney disease (ADPKD). We examined whether nutritional status is associated with the preservation of kidney function, using a cohort of typical ADPKD. Methods: We enrolled ambulatory ADPKD patients in 9 tertiary medical centers in Korea from May 2019 to December 2021. We excluded patients who were aged less than 18 years, who had known end-stage kidney disease at the time of enrollment, who had a diagnosis of atypical ADPKD, and who were Tolvaptan users. The primary outcome was an estimated glomerular filtration rate (eGFR) decline >3 mL/min/1.73 m², based on nutritional status assessed by subjective global assessment (SGA). We also evaluated an eGFR decline >1 mL/min/1.73 m², an increase in urine protein–creatinine ratio (UPCR) > 0, and an increase in UPCR >0.3 as secondary outcomes, based on SGA after the 1-year follow-up. A logistic regression (LR) model was used to calculate the odds ratio (OR) for the primary outcome. Because there were differences in several baseline variables, such as Mayo classification, serum hemoglobin, serum creatinine, and UPCR between SGA groups, we matched propensity scores. Results: In total, 805 patients were prospectively enrolled. Among them, 236 patients who had 1-year follow-up data and typical imaging findings were analyzed to evaluate the effect of nutritional status on kidney function. SGA was used to assess the nutritional status. The mean age was 45.0 ± 13.3 years, and 49.6% of the patients were female. The mean eGFR was 81.9 mL/min/1.73 m². Among the 236 patients, 91 (38.6%) experienced a 1-year eGFR decline >3 mL/min/1.73 m². When a multivariable LR was applied, SGA 3-6 was identified as a significant factor related to a 1-year eGFR decline >3 mL/min/1.73 m² (adjusted OR = 1.22 [1.04-1.43]; P =.017). Despite matching propensity scores, the 1-year eGFR decline >3 mL/min/1.73 m² was still higher in the SGA 3-6 group regardless of proteinuria. Conclusion: Good nutritional status is associated with better-preserved kidney function in non-obese typical ADPKD patients who do not take Tolvaptan.