The epidemiology of psoriatic arthritis in Israel – a population-based study

Abstract Background There is limited information on the epidemiology of psoriatic arthritis (PsA) in general and in Middle Eastern populations in particular. The aims of this study were to estimate the prevalence and incidence rates of PsA and their temporal trends in the general population in Israel. Methods In this study, a cohort of adult patients with PsA was derived from the database of Clalit Health Services (CHS), Israel’s largest health fund, with over 4.4 million members. The crude and age- and sex-standardized prevalence and incidence rates of PsA from 2006 to 2015 in the general population were calculated. The variation in PsA prevalence was assessed in relation to several demographic factors. Results Among the 2,931,199 individuals aged 18 years and older registered in the CHS database in 2015, 4490 patients had a diagnosis of PsA (322 incident cases), resulting in overall crude prevalence and incidence rates of 0.153% (95% CI 0.149%, 0.158%) and 10.9 (95% CI 9.8, 12.3) per 100,000 population, respectively. The reported prevalence of PsA in Israel has doubled between 2006 and 2015 (from 0.073% to 0.153%). In contrast, the global incidence rate remained stable, with a gradual increase in incidence among individuals aged 51 to 70 years. PsA is associated with Jewish ethnicity, high socioeconomic status, and higher body mass index. Conclusions The prevalence and incidence of PsA in Israel are within the range of previous estimates from Southern European populations. An increase in the reported prevalence of PsA was observed over the past decade in the general population in Israel

Autoimmune Thyroid Diseases and Thyroid Cancer in Pemphigus: A Big Data Analysis

There is a little consensus regarding the association of pemphigus with autoimmune thyroid diseases. While this association had been confirmed by some observational studies, others had refuted it. We aimed to study the association between pemphigus and Hashimoto's thyroiditis, Grave's disease, and thyroid cancer using a large-scale real-life computerized database. A cross-sectional study was performed to compare pemphigus patients with age-, sex-, and ethnicity-matched control subjects regarding the prevalence of overt thyroid diseases. Chi-square and t-tests were used for univariate analysis, and a logistic regression model was used for multivariate analysis. The study was performed using the computerized database of Clalit Healthcare Services ensuring 4.5 million individuals. A total of 1,985 pemphigus patients and 9,874 controls were included in the study. The prevalence of Hashimoto's thyroiditis (12.9 vs. 11.9%; P = 0.228), Graves's disease (0.7 vs. 0.7%; P = 0.986), and thyroid cancer (0.7 vs. 0.5%; P = 0.305) were comparable among patients with pemphigus and control subjects. In sex-stratified analysis, pemphigus associated significantly with Hashimoto's thyroiditis among male patients (OR, 1.36; 95% CI, 1.04–1.79). In multivariate analysis adjusting for potential confounding factors, no independent associations between the conditions were revealed. Study findings were robust to sensitivity analysis that included only patients under pemphigus-specific treatments. In conclusion, Hashimoto's thyroiditis was found to be associated with pemphigus only among male patients, but not among all patients. Physicians treating patients with pemphigus might be aware of this possible association. This study does not provide a clue for an association of pemphigus with Grave‘s disease or thyroid cancer