INCREASED PREVALENCE AND HIGHER 1-YEAR MORTALITY OF PATIENT HOSPITALIZED FOR AORTIC STENOSIS WITH COMORBID CHRONIC KIDNEY DISEASE IN THE PROVINCE OF QUEBEC, CANADA

Abstract

Abstract Objective: Development of aortic stenosis is associated with valvular calcifications which are highly prevalent in chronic kidney disease (CKD). The objective of this study was to evaluate the temporal trends in the prevalence and 1-year mortality of patients hospitalized for aortic stenosis according to comorbid CKD status in the province of Quebec, between 2000–2017. Design and method: Using the Quebec Integrated Chronic Disease Surveillance System, we identified patients aged 20 years and older with incident aortic stenosis using International Classification of Diseases diagnostic codes versions 9 and 10, in the hospital discharge database. We subsequently combined hospital discharges and physician billing claims databases to identify patients with comorbid CKD in the two years prior to aortic stenosis’ diagnosis. Three subgroups of CKD were considered: 1) non-CKD, 2) pre-dialysis and 3) dialysis. The distribution of the 2016–2017 aortic stenosis population was used for age-standardization of prevalence, 1-year all-cause and cardiovascular mortality. Results: We included 108 780 patients with incident aortic stenosis (females: 51.8%; mean age (±SD): 76.4 ± 11.7; comorbid CKD status: 80 768 non-CKD; 26 809 pre-dialysis; 1 203 dialysis). During the study period, the age-standardized prevalence of non-CKD patients decreased by 14% (80.72% [95% CI 77.56–83.99] to 69.56% [95% CI 67.23–71.94]; Figure 1). Inversely, the age-standardized prevalence of pre-dialysis and dialysis patients increased by 58% (18.52% [95% CI 16.93–20.21] to 29.33% [95% CI 27.82–30.91]) and 46% (0.76% [95% CI 0.51–1.11] to 1.11% [95% CI 0.84–1.44]), respectively. Age-standardized 1-year all-cause and cardiovascular mortality decreased over time but remained higher in patients with comorbid CKD. In 2015–2016, age-standardized relative risk of 1-year all-cause mortality was significantly higher in pre-dialysis (RR = 1.56 [95% CI 1.44, 1.69]) and dialysis (RR = 2.04 [95% CI 1.62–2.61]) than in non-CKD patients. Age-standardized relative risk of 1-year cardiovascular mortality was also significantly higher in pre-dialysis (RR = 1.83 [95% CI 1.66–2.03]) and dialysis (RR = 2.28 [95% CI 1.68–3.09]) than in non-CKD patients. Conclusions: Prevalence of patients with incident aortic stenosis and comorbid CKD increased between 2000–2017. 1-year all-cause and cardiovascular mortality improved over time but remain higher in aortic stenosis patients with comorbid CKD.