Particulate matter air pollution effects on pulmonary tuberculosis activation in a semi-desert city on the US-Mexican border

Abstract

In this paper we assessed the association (relative risk, RR) between the exposure to PM₁₀ and PM_2.5 (as a continuous variable and as categories of low or high pollution exposure) on the incidence of pulmonary tuberculosis (PTB) in Mexicali, Baja California, Mexico. We used a weekly, lagged multiple Poisson regression model. We observed a 10-week delayed effect for PM₁₀ and PM_2.5 in all PTB cases and in male cases with PTB. An 11-week delayed effect occurred in the female PTB cases. For all the PTB cases, the RR rose by 2.4% (95% CI: 2.1, 2.6, p<0.10) for each 10 µg/m³ increase of PM₁₀ in the continuous exposure and by 3.6% (CI: 3.3, 4.0, p<0.05) in the high pollution exposure category, and by 3.2% (CI: 2.9, 3.4, p<0.05) for each 10 µg/m³ increase of PM_2.5 in the continuous exposure and by 3.9% (CI: 3.6, 4.3, p<0.05) in the high pollution exposure category. In men, the RR rose by 2.8% (CI: 2.5, 3.1, p<0.10) for each 10 µg/m³ increase of PM₁₀ in the continuous exposure and by 4.6% (CI: 4.2, 5.0, p<0.05) in the high pollution exposure category, and by 3.4% (CI: 3.1, 3.7, p<0.05) for each 10 µg/m³ increase of PM_2.5 in the continuous exposure and by 4.2% (CI: 3.8, 4.6, p<0.05) in the high pollution exposure category. In women, the RR rose by 5.1% (CI: 4.7, 5.5, p<0.05) for each 10 µg/m³ increase of PM₁₀ in the continuous exposure and by 5.3% (CI: 4.7, 5.8, p<0.10) in the high pollution exposure category, and by 4.3% (CI: 3.8, 4.8, p<0.10) for each 10 µg/m³ increase of PM_2.5 in the continuous exposure and by 5.3% (CI: 4.8, 5.9, p<0.10) in the high pollution exposure category. PM air pollution appears to associate with the incidence of PTB in the population of Mexicali.