Epidemiology of Granulomatosis with Polyangiitis in Poland, 2011-2015.

Granulomatosis with polyangiitis (GPA) is a form of vasculitis that affects small- and medium-sized vessels in many organs. The aim of the study was to describe the epidemiology of GPA in Poland in 2011-2015, including the incidence and prevalence rates. The authors conducted a retrospective, population-based study, using hospital discharge records with GPA diagnosis. GPA incidence was estimated on the basis of the data from the Polish hospital morbidity study carried out by the National Institute of Public Health. The final study group consisted of 1491 patients (749 females, 742 males) who were first time hospitalized with the diagnosis of GPA. The average annual incidence of GPA in Poland was 7.7/1,000,000 (95% CI, 4.1-11.4), and the point prevalence at the end of 2015 was 36/1,000,000. A statistically significant decrease in the GPA incidence was noticed in this study. A 1-year survival rate for GPA was 94%. In conclusion, the incidence and prevalence rates of GPA in Poland are similar to that reported in other European countries. The study provides recent epidemiological data on GPA in Poland, which may be useful for comparisons with other geographical regions.