Quality of Life in Autosomal Dominant Polycystic Kidney Disease Patients Treated With Tolvaptan

Abstract

Rationale & Objective: The impact of tolvaptan on health-related quality-of-life (HRQoL) in patients with autosomal dominant polycystic kidney disease (ADPKD) is unknown. To address this knowledge gap, we studied patient-reported HRQoL in patients enrolled in the Bern ADPKD registry. Study Design: Prospective cohort study. Settings & Participants: Inclusion criteria were age 18 years or older, clinical diagnosis of ADPKD, and informed consent. The main exclusion criterion was need for kidney replacement therapy. Outcome: HRQoL was assessed using the standardized Kidney Disease Quality of Life Short Form (KDQOL-SF) questionnaire at start of the study (baseline) and after 1 year (follow-up). The KDQOL-SF has 2 parts: a generic 36-Item Health Survey instrument with 8 subscores and 2 summary scores and a kidney disease–specific instrument to assess health concerns. Higher scores indicate better HRQoL. The influence of tolvaptan treatment on HRQoL and kidney-specific health concerns was analyzed using analysis of covariance, adjusting for HRQoL and health concerns before the start of the study, sex, and age. Results: In 38 of 121 registry patients, tolvaptan treatment was initiated. Within the first 3 months, treatment had to be discontinued in 6 (16%) patients due to aquaretic side effects (n = 4; 11%) or elevated liver enzyme levels (n = 2; 5%), and a dose reduction was necessary in 8 (21%) patients. We included 98 patients (30 with and 68 without tolvaptan treatment) in the analysis for which baseline and 1-year follow-up data were available. At follow-up, and after adjusting for baseline scores, sex, and age, HRQoL and kidney-specific health concerns were not influenced by tolvaptan treatment, except for patient satisfaction, which was increased. Limitations: Observational study design, monocentric study at tertiary referral hospital, almost exclusively white study population, grant support by Otsuka Pharmaceuticals. Conclusions: Our results indicate that tolvaptan does not significantly affect HRQoL in patients with ADPKD who tolerate treatment beyond the first 3 months of therapy. Index Words: ADPKD, tolvaptan, HRQoL, quality of life