Life table analysis of feline polycystic kidney disease in Japan

Feline polycystic kidney disease (PKD) is an inherited renal disorder observed in various breeds. Analyses of life expectancy and distribution of age at death among cats are not well documented. The current study preliminarily assessed life expectancy, cumulative survival rates, and distribution of age at death in cats with PKD by performing a follow-up investigation. This retrospective cohort study was conducted on 300 cats that tested positive for the feline PKD1 variant (c.10063C >A) in Japan. A life table analysis was performed, and a distribution graph of age at death was generated. The life expectancy at birth was approximately 12.7 years, with a 5- and 10-year cumulative survival rates of 95.1% and 61.3%, respectively. Of the 300 cats, 48 (16.0%) progressed to uremia, and 62 (20.7%) died of renal failure and other causes. The median age at death in 62 cats was 8 years, with the first decile being 5 years. The highest number of deaths was at the age of 7 years. The cumulative survival rate began to decline significantly at the age of 6-7 years. This study first performed a survival analysis of feline PKD and provided an important basis for understanding the patterns of overall mortality associated with this genetic disorder. Our findings emphasized the importance of frequent examination at a young age, with consideration of the remarkable decrease in the cumulative survival rate between the ages of 6 and 7 years.