Prevalence and incidence of systemic lupus erythematosus in the adult population of Estonia.

Studies have demonstrated considerable variability in systemic lupus erythematosus (SLE) incidence and prevalence estimates. Lack of reliable epidemiological data may hinder evidence-based health care planning. The aim of the present study was to estimate the prevalence and incidence of SLE in the Estonian adult population. The SLE billing cases were extracted from the Estonian Health Insurance Fund database 2006-2010 and verified using health care providers' databases. The patients' life status data for January 1, 2011, were retrieved from the Estonian Population Register. The calculations for the estimates' lower limits were based on verified cases only; the upper limits calculations also accounted for the billing cases for which clinical data were unavailable. The period prevalence of SLE was between 39 and 48 per 100,000 and incidence rate between 1.5 and 1.8 per 100,000 person-years. The point prevalence on January 1, 2011, was between 37 and 40 per 100,000. The estimates are comparable with internationally published figures and can be used to enhance evidence-based health care planning. The high percentage of billing cases that could not be verified using clinical data supports the argument that epidemiological studies based solely on administrative databases are usually of low reliability.

The prevalence of rheumatoid arthritis in Estonia: an estimate based on rheumatology patients' database.

Sound epidemiological data are a basic requirement for decision making on the allocation of health care resources. Unfortunately, this is not the case in Estonia, where the paucity of epidemiological data has impeded health care planning for rheumatic conditions. The current paper presents the first effort to explore the epidemiology of rheumatoid arthritis (RA) in Estonia. Electronic databases of all rheumatology units of Harju County, three national and one private, were searched for the records of RA (ICD-10 diagnoses M05 and M06.0) patients who had visited a rheumatologist during 2006 or 2007. Prevalence of RA was calculated for the age 20 years and older and for subsets according to age and gender, using the numbers from the patients' database in the numerator and the corresponding population numbers in the denominator. The total number of prevalent RA cases was 1,897, of which 85 % (n = 1,605) were women. The overall crude period prevalence 2006-2007 of RA in Harju County for the age group 20 years and older was 0.46 %. RA prevalence for both sexes increased with age until the age of 70-79 years and decreased subsequently. Prevalence of RA was significantly higher for women compared with men in all age groups. The prevalence of RA among women and men 20 years and older was 0.70 % (6.68-7.37) and 0.16 % (1.42, 1.79), respectively. Age-standardized (European population) prevalence rate was 0.44 %. The results are concordant with epidemiological data on RA prevalence derived recently in other European countries.