Medical and statistical and epidemiological characteristics of the prevalence of myasthenia gravis in Ukraine

The aim was to study the prevalence of myasthenia gravis among adults in certain regions of Ukraine. Materials and methods. The biostatistical method to confirm the representativeness of the sample and for the statistical processing of data was used in the study. To analyze the indicators of public health associated with myasthenia gravis, in particular the prevalence of myasthenia gravis and disability, we used the medical and statistical method with the calculation of relative general indicators, standardized indicators and indicators of visibility. To study the characteristics of the prevalence of myasthenia gravis in Ukraine, the epidemiological method of studying the incidence was used. By design, the conducted epidemiological study refers to descriptive cross-sectional studies. A study of the prevalence of myasthenia gravis in Ukraine was carried out on a sample including data from ten regions of Ukraine. Results. In total, in 2014, 757 cases of myasthenia gravis were studied in selected territories, among them 465 (61.43%) among urban residents, 292 (38.57%) among rural residents. The average annual prevalence of myasthenia gravis was 5.16 (95% confidence interval 4.79–5.53) cases per 100,000 population and ranged 2.97–6.09 per 100 thousand population (respectively, in the Volyn and Mykolaiiv regions). Among the investigated cases of myasthenia gravis there were 637 (84.15%) cases of the generalized and 94 (12.42%) — of the ocular form of the disease. Almost a third of patients — 205 (27.08%) had thymoma, 224 (29.59%) underwent thymectomy (in the past), 488 (64.46%) had a disability. The vast majority of these cases of disability occured in the age group <60 years — 547 (72.26%). Mean age of diagnosis was 36.0 (25.0–51.0) years, with statistically significant differences only in individual territories. The age of diagnosis among women was significantly lower — 34.0 (25.0–47.0) years compared with men — 47.0 (30.0–58.0) years (p<0.001). An analysis of the diagnosis age showed that in women the peak of the disease prevalence ranges 20–30 years old (p<0.001) was found in almost a third of cases (28.2%), while every fifth man (21.5%) has had diagnosis of myasthenia in the age 50–60 years (p<0.001). Conclusion. The prevalence of myasthenia gravis in Ukraine was lower compared with data from other countries, which may indicate an insufficient diagnosis and accounting of patients with this nosology.