Hospital admissions for ambulatory care-sensitive conditions among people with gout and other crystal arthropathies in Alberta, Canada: a population-based matched cohort study

Background Admissions for ambulatory care sensitive conditions (ACSCs) are used as an indicator of access and quality of care. Our aim was to estimate hospitalization rates for national indicator ACSCs in people with crystal arthropathies relative to the general population. Methods We conducted a population-based matched cohort study of persons with crystal arthropathies and age and sex-matched unexposed controls using administrative data from Alberta, Canada from years 2002–2023. We applied ICD-10-CA code-based case definitions for Canadian ACSCs. We calculated incidence rate ratios (IRRs) for any ACSC and each individual condition at 3 and 5 years after index date using zero-inflated Poisson regression modelling. We examined effects of sex, age, location of residence, and socioeconomic status on estimates. Findings There were 129,378 individuals meeting the case definition for crystal arthropathies. In cases 11.6% of all hospital admissions (n = 20,889/180,696) were for an ACSC, compared to 9.5% (n = 10,607/111,102) in matched unexposed. People with crystal arthropathies had an increased risk of an ACSC admission at 3 years (adjIRR 1.12, 95% CI, 1.05–1.18) and 5 years (adjIRR 1.14, 95% CI, 1.09–1.19) driven primarily by heart failure. Older age, rural residence and lower socioeconomic status were associated with increased admission rates. Interpretation Case status was associated with an increased risk of being hospitalized for ACSCs compared to the general population. Older age, rural residents, and those who experience material and social deprivation were at highest risk. High-quality care for disease and comorbidity management that is attentive to the social determinants of health is required to optimize care. Funding Canadian Institutes of Health Research.