Spatial Distribution of Smear-Positive Pulmonary Tuberculosis Incidence Rates in Iran: A Registry-Based Study (2018-2022).

Background: Smear-positive pulmonary tuberculosis (SPPTB) is a significant public health concern in Iran. This registry-based study aimed to investigate the incidence rates of SPPTB in Iran from 2018 to 2022. Methods: The study analyzed SPPTB cases using the Spatial Lag Model to investigate the spatial distribution of SPPTB incidence rates, income inequality, and delayed diagnosis across the provinces of Iran and mapped the results using GIS maps. Results: The study found that SPPTB is prevalent among older individuals and males. The analysis identified significant spatial variation in the distribution of SPPTB incidence rates, income inequality, and delayed diagnosis across the provinces. The highest incidence rate of SPPTB was found in Sistan and Baluchestan Province and Golestan provinces. The study found a positive association between income inequalities, measured by the Gini index, and SPPTB incidence rates, indicating that provinces with higher income inequality may have higher incidence rates of SPPTB. The negative correlation with delayed diagnosis implies that predominantly, SPPTB cases are identified in the early months. Conclusions: The study highlights the need to address socioeconomic disparities in health outcomes and implement targeted interventions in areas with higher income inequality to reduce the burden of SPPTB in Iran. Despite decreased SPPTB incidence rates in Iran over the past decade, some regions, such as Sistan and Baluchestan, still have high incidence rates. The Iranian government has implemented policies and programs to reduce income inequality and delayed diagnosis within the country, which can contribute to reducing the burden of SPPTB.