Hospitalizations in sarcoidosis: a cohort study of a universal healthcare population

Rationale — Population-based analyses of hospitalization rates from countries with universal healthcare systems are lacking for patients with sarcoidosis.

Objectives — We aimed to evaluate the long-term trends in hospitalization rates and risk factors for hospitalization in patients with sarcoidosis in Ontario, Canada.

Methods — We performed a cohort study using health administrative data from Ontario, Canada, between 1996 and 2015. Patients with sarcoidosis were identified by using two or more physician visits and International Classification of Diseases codes. All-cause and sarcoidosis-related hospitalization rates were age and sex standardized. Hospitalization rates between groups were analyzed by using Cochran-Armitage and Breslow-Day tests. Associations between patient characteristics and hospitalization rates were evaluated by using multivariable Poisson regression.

Results — In total, 18,550 individuals with sarcoidosis experienced 33,516 all-cause and 1,725 sarcoidosis-related hospitalizations. Adjusted all-cause hospitalization rates decreased from 206.4 to 152.1 per 1,000 cases between 1996 and 2015 (26% decrease; P < 0.001). The largest decrease in all-cause hospitalization occurred in patients 18–25 years old (67% decrease; P < 0.001). Adjusted sarcoidosis-related hospitalization rates decreased from 21.8 to 4.2 per 1,000 cases between 1996 and 2015 (81% decrease; P < 0.001). The decrease in sarcoidosis-related hospitalizations was largest in women compared with men (87% vs. 72%; P = 0.004) and in those 26–35 years old (91% reduction; P < 0.001). Lower income (risk ratio, 1.27 [1.18–1.37]; P < 0.001) and rural residence (risk ratio, 1.16 [1.08–1.24]; P < 0.001) were associated with increased all-cause hospitalizations.

Conclusions — Hospitalization rates in patients with sarcoidosis have decreased over the past 20 years, most substantially in patients of younger age. Important differences in the risk of hospitalization exist on the basis of sex, socioeconomic factors, and geographic factors in patients with sarcoidosis.