Background: Autoimmune thyroiditis (AT) is one of the most common endocrine disorders affecting a significant percent of the population, especially women. It may have serious and long-lasting consequences. The etiology of AT is multifactorial and it arises from an interplas between environmental and genetic factors. Tendencies in AT prevalence and incidence are unclear. In Poland there are no national registers covering the data on AT prevalence.
Objectives: The aim of the investigation was to assess changes in diagnosing AT in the largest chain of outpatient medical centers in Poland.
Material and methods: We compared freqnancy at which AT and hypothyroidism diagnoses were made during endocrinology consultations in the period 2006-2013. The data was extracted from the database of LUXMED (part of BUPA).
Results: Within 8 years, the prevalence of newly diagnosed AT dropped from 10.4% to 4.8% (p < 0.001) alongside with a decrease in the prevalence of newly diagnosed hypothyroidism from 17.8% to 7.7% (p < 0.00001). AT was widespread in young women aged 20-39. There were relatively more cases in the southern areas of Poland.
Conclusions: The analyzed data does not support a hypothesis indicating a growing incidence of AT in the last years. Detailed epidemiological studies would be helpful in designing screening strategies for patients with this common disorder.
Keywords: autoantibodies; autoimmune thyroiditis; hypothyroidism; prevalence.