Preventable Hospital Admissions in Persons with Psoriatic Arthritis and Axial Spondyloarthritis: A Population-Based Study

Objectives Hospitalization rates for ambulatory care sensitive conditions (ACSCs, inclusive of grand mal seizures, chronic lower respiratory diseases, asthma, diabetes, heart failure and pulmonary edema, hypertension, and angina) are used nationally as indicators for health system quality, reflecting how appropriate ambulatory care can prevent admissions. We aimed to estimate the rates of ACSC hospitalizations in people with psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) compared to matched controls. Methods Linked administrative health datasets from the province of Alberta were used to create a combined incident cohort based on validated ICD codes for PsA and axSpA from years 2002-2023. Controls were selected in a 4:1 ratio matched for age and sex. We used the Canadian Institute for Health Information ACSC ICD-10-CA case definitions to identify hospitalizations from the Discharge Abstract Database as our outcome of interest.[1] We calculated incidence rate ratios (IRR) at 3 and 5 years from the date of the first PsA and/or axSpA diagnosis using a multivariable regression model adjusting for age, sex, location of residence, and socioeconomic status using the Pampalon Deprivation Index. Results There were 16,054 individuals with incident PsA and/or axSpA over the study period (45% male, mean age 59 years, 78% urban, 31% with both material and social deprivation). Of these, 40.3% (n=6,467) hat at least 1 hospital admission for any reason, with a total of 22,516 unique hospitalizations, compared to 27.2% (n=18,665) of controls with 48,350 unique hospitalizations. ACSC hospitalizations accounted for 6.4% (n=1,433) of all admissions in persons with PsA/axSpA, compared to 8.0% (n=3,856) of all admissions in controls. In both cohorts, chronic lower respiratory diseases were the most frequent reasons for an ACSC admission (40% in cases, 41% in controls). After adjusting for age, sex, location of residence, and socioeconomic status, the IRR for an ACSC hospitalization was increased at 3 years (IRR 1.35, 95% CI 1.16, 1.57) and 5 years (IRR 1.23, 95% CI 1.10, 1.38) in those with PsA and/or axSpA compared to controls (Table 1). Among individual ACSCs, the IRR for diabetes-related admission was increased by 65% (IRR 1.65, 95% CI 1.14, 2.39) and angina-related admissions nearly 3-fold higher (IRR 2.74, 95% CI 1.58, 4.75) at 5 years relative to controls. Table 1. Incidence rate ratios (95% CI) for Ambulatory Care Sensitive Condition Hospitalizations, in persons meeting the case definition for psoriatic arthritis or axial spondyloarthritis compared to age and sex matched controls Conclusion People with PsA and/or axSpA are at a higher risk of being hospitalized for ACSCs compared to the general population, with a signal for higher diabetes and angina-related admissions in established diseases. An enhanced focus on risk reduction is indicated. References [1.] Canadian Institute for Health Information. https://www.cihi.ca/en/indicators/ambulatory-care-sensitive-conditions-hospitalizations