Spatiotemporal Patterns and Socioeconomic Determinants of Pulmonary Tuberculosis in Piauí, Northeast Brazil, 2001-2024

Background Pulmonary tuberculosis (PTB) remains a major public health problem, strongly associated with social and territorial inequalities. This study aimed to analyse temporal trends, spatiotemporal transmission patterns and socioeconomic determinants of PTB in the state of Piauí, Northeast Brazil, from 2001 to 2024. Methods An ecological study was conducted using official surveillance data on newly reported PTB cases at the municipal level. Temporal, spatial and spatiotemporal analytical methods were applied to investigate long-term trends, transmission patterns and socioeconomic determinants associated with PTB incidence. Results A total of 17,186 PTB cases were reported. Time-series analysis showed a sustained decline in incidence between 2001 and 2015, followed by a period of gradual recovery starting in 2016. Seasonality remained stable, with peaks occurring between April and June. Persistent spatial heterogeneity was identified, with higher-risk clusters concentrated in urban municipalities. Multivariate spatiotemporal time-series analysis revealed the predominance of the endemic component, with a secondary contribution from the autoregressive component and minimal contribution from the spatiotemporal component. In the spatial Bayesian analysis, PTB incidence was associated with AIDS incidence (Relative Risk [RR] = 1.11; 95% Credible Interval [CrI]: 1.05-1.18), the number of nurses per 1000 inhabitants (RR = 1.08; 95% CrI: 1.03-1.13) and per capita municipal health expenditure (RR = 0.94; 95% CrI: 0.89-0.98). Conclusions PTB in the Piauí exhibited heterogeneous spatiotemporal patterns, being sustained primarily by endemic factors and persistent structural inequalities. Control strategies should be territorially targeted, considering local transmission patterns and the identified determinants.