Prevalence and comorbidities of Sjogren's syndrome patients in the Community of Madrid: A population-based cross-sectional study

•SS prevalence varies widely due to geolocation, studied populations, classification criteria and epidemiologic methodologies.•Disease diagnosis may be delayed, omitted, or misclassified as another rheumatic or nonrheumatic disease.•Health care policies facilitate early diagnosis and improve SS management and patients’ quality of life. To estimate the prevalence, sociodemographic characteristics and comorbidities of Sjogren's syndrome (SS) patients in the Community of Madrid. A population-based cross-sectional cohort of SS patients was derived from the information system for rare diseases in the Community of Madrid (SIERMA) and confirmed by a physician. The prevalence per 10,000 inhabitants among people aged ≥18years in June 2015 was calculated. Sociodemographic data and accompanying disorders were recorded. Univariate and bivariate analyses were performed. A total of 4,778 SS patients were confirmed in SIERMA; 92.8% were female, with a mean age of 64.3 (standard deviation=15.4) years. A total of 3,116 (65.2%) patients were classified as primary SS (pSS), and 1,662 (34.8%) as secondary SS (sSS). The prevalence of SS among people aged ≥18 years was 8.4/10,000 (95%Confidence interval [CI]=8.2–8.7). The prevalence of pSS was 5.5/10,000 (95%CI=5.3–5.7), and that of sSS was 2.8/10,000 (95%CI=2.7–2.9), with rheumatoid arthritis (20.3%) and systemic lupus erythematosus (8.5%) being the most prevalent associated autoimmune diseases. The most common comorbidities were hypertension (40.8%), lipid disorders (32.7%), osteoarthritis (27.7%) and depression (21.1%). The most prescribed medications were nonsteroidal anti-inflammatory drugs (31.9%), topical ophthalmic therapies (31.2%) and corticosteroids (28.0%). The prevalence of SS in the Community of Madrid was similar to the overall prevalence worldwide observed in previous studies. SS was more frequent in women in their sixth decade. Two out of every three SS cases were pSS, while one-third were associated predominantly with rheumatoid arthritis and systemic lupus erythematosus.