The epidemiological situation of tuberculosis in Poland: Part I. According to notification rates, the incidence of tuberculosis varies in different regions of Poland: is this true?

Introduction: In 2012 the incidence rate of tuberculosis in Poland was 19.6/100,000 but these was great variability between regions concerning notification rates (from 10.9/100,000 to 30.2/100,000). The aim of the study was to assess whether there are elements that might confirm that these differences are true. To answer this question, we compared the population of TB patients from regions with higher notification rates to the population of patients from regions with lower notifications rates. The data collected during three consecutive years were analysed. We selected for comparison the regions with the lowest and highest notification rates and those in which the notification rates for 3 years (2010-2012) were relatively stable.

Material and methods: Eight regions were chosen: three regions (Group I) with high notification rates (from 23.7 to 32.3/100,000 - mean rates in the analysed period of time) and five (Group II) with low notification rates (mean rates from 12.2 to 18.6/100,000).

Results: It was found that the proportion of sputum culture-positive patients was significantly higher in Group II. Thus, the difference in the notification rate of cases with culture-confirmed tuberculosis was smaller than the difference in the whole notification rate. Nevertheless, it was still significant. Tubercle bacilli in patients from Group I were significantly more often resistant to one drug. The incidence of chronic fibro-cavernous disease and of tuberculous pneumonia was significantly higher in Group I. The proportion of patients with symptoms was higher in Group I than in Group II. In addition, patients in Group I had the so-called primary tuberculosis (tuberculous pleuritis and tuberculous lymphadenopathy in the chest) significantly more often. It was also found that among patients from Group I there were significantly more children, more (though not significantly) youngsters and significantly fewer elderly patients.

Conclusions: Based on these observations, it was concluded that there is a real difference in the epidemiological situation of tuberculosis in the selected regions of Poland with high and low rates of notification. Possible causes of this situation will be presented in a following publication.