Epidemiology and health outcomes of sarcoidosis in a universal healthcare population: a cohort study

Abstract

Sarcoidosis-related mortality appears to be rising in North America, with increasing rates in females and the elderly. We aimed to estimate trends in sarcoidosis incidence, prevalence and mortality in Ontario, Canada.We performed a cohort study using health administrative data from Ontario between 1996 and 2015. International Classification of Diseases and Ontario Health Insurance Plan codes were used for case detection. Three disease definitions were created: 1) sarcoidosis, two or more physician claims within 2 years; 2) chronic sarcoidosis, five or more physician claims within 3 years; and 3) sarcoidosis with histology, two or more physician claims with a tissue biopsy performed between claims.Overall, 18 550, 9199 and 3819 individuals with sarcoidosis, chronic sarcoidosis and sarcoidosis with histology, respectively, were identified. The prevalence of sarcoidosis was 143 per 100 000 in 2015, increasing by 116% (p<0.0001) from 1996. The increase in age-adjusted prevalence was higher in males than females (136% versus 99%; p<0.0001). The incidence of sarcoidosis declined from 7.9 to 6.8 per 100 000 between 1996 and 2014 (15% decrease; p=0.0009). A 30.3% decrease in incidence was seen among females (p<0.0001) compared with a 5.5% increase in males (p=0.47). Age- and sex-adjusted mortality rates of patients with sarcoidosis rose from 1.15% to 1.47% between 1996 and 2015 (28% increase; p=0.02), with the overall trend being nonsignificant (p=0.39). Mortality rates in patients with chronic sarcoidosis increased significantly over the study period (p=0.0008).The prevalence of sarcoidosis is rising in Ontario, with an apparent shifting trend in disease burden from females to males. Mortality is increasing in patients with chronic sarcoidosis.