Patient-Reported Disease Burden Predicts Odds of ADPKD Hospitalization – Renal and Urology News

Disease-specific instruments best capture the burden of autosomal dominant polycystic kidney disease (ADPKD) on patients and predict clinical outcomes, including hospitalization and sick days from work.

The original OVERTURE trial (NCT01430494) included 3409 real-world patients with ADPKD from all ages (12-78 years) and stages of chronic kidney disease (CKD).¹ Each additional 1 mL/m of height-adjusted total kidney volume (htTKV) on MRI was significantly associated with worse outcomes, including lower estimated glomerular filtration rate (eGFR) and 25%, 22%, and 35% increased odds of hypertension, kidney pain, and hematuria, respectively. Greater baseline htTKV also was significantly associated with decreased work productivity and increased health care resource utilization.

The current analysis gauged disease-specific and generic health-related quality of life (HRQoL) using patient-reported outcomes.² The ADPKD-Impact Scale (ADPKD-IS) measured ADPKD-related physical and emotional symptoms and fatigue over the past 2 weeks. The ADPKD-Urinary Impact Scale (ADPKD-UIS) evaluated ADPKD-related daytime and nighttime urinary burden over 1 week.

Worse assessment scores on both of these validated instruments, particularly on the ADPKD-IS physical subscale, strongly predicted a 1.3- to 1.8-fold increased likelihood of hospitalization within 6-18 months, Dorothee Oberdhan, MS, of Otsuka Pharmaceutical Development & Commercialization, Inc. in Rockville, Maryland, and colleagues reported in Kidney Medicine. Worse assessment scores, especially on the ADPKD-IS physical subscale and ADPKD-UIS urgency subscale, also strongly predicted a 1.2- to 1.8-fold increased likelihood of sick days.

The Brief Pain Inventory-Short Form was not very predictive. Instead, the researchers proposed using a disease-specific assessment such as the recently validated ADPKD Pain and Discomfort Scale (ADPKD-PDS), which is under development. The ADPKD-PDS contains 20 items assessing pain severity and interference with daily activities over a 7-day recall period. The international effort including 46 focus groups and 293 adult patients defined 3 distinct types of ADPKD-related pain and discomfort: chronic dull kidney pain, chronic discomfort/fullness, and rare/intermittent sharp kidney pain.³

All of the ADPKD-specific instruments are suitable across CKD stages. The investigators found that patient-reported outcomes substantially worsen in CKD stages G4 or G5.

“Measures of pain, urinary urgency or frequency, and disease-specific physical burden exhibited the strongest associations with medical resource utilization and impact on employment,” Oberdhan’s team wrote. “These findings underscore the utility and importance of a disease-specific PRO measure in ADPKD, as instruments designed for kidney disease in general do not capture burden before end-stage kidney disease in ADPKD.”

Disclosure: This research was supported by Otsuka Pharmaceutical. Please see the original reference for a full list of disclosures.