Is there an association between air pollution levels and lung cancer incidence?

Abstract

e13584 Background: PM2.5 particles are an indicator of air pollution levels associated with various respiratory illnesses. We sought to determine the association between air pollution levels and lung cancer incidence across different countries. Methods: Country-specific data for median PM2.5 levels and age-standardized lung cancer incidence rates (ASLCIR) were collected for the year 2016 from the World Health Organization and the Global Cancer Observatory, respectively. Country-specific data for median age and proportion of smokers were collected from the Central Intelligence Agency and Our World in Data, respectively. Statistical analyses were performed using SPSS Version 26.0. Results: Across 105 countries, the median PM2.5 level was 18 ug/m3 (range; 6-94 ug/m3). The WHO has set 10 ug/m3 as the upper limit for PM2.5 levels; 91 (86.7%) of countries had rates higher than this. The ASLCIR was surprisingly higher in countries with PM2.5 ≤ 10 ug/m3 (median 28.7 vs. 13.9 per 100,000 population, Pearson correlation coefficient -0.386, p < 0.001). Countries with PM2.5 levels ≤ 10 ug/m3 tended to have a higher GDP (median $55,709 vs. $5,931, p < 0.001), and an older population (median 41.5 vs. 30.4, p < 0.001); however, the proportion of population who smoked was no different in countries with low vs. high PM2.5 levels (20.3% vs. 22.5%, p = 0.847). Controlling for age, GDP, and proportion of the population who smoke in a multiple linear regression model, ASLCIR were not influenced by median PM2.5 (see linear regression table below, p = 0.888). Removing PM2.5 levels from the model did not significantly affect the model fit (R2= 0.749 in both models). Conclusions: These results demonstrate that air pollution levels do not significantly impact lung cancer incidence rates, which are more related to age, tobacco use, and GDP. [Table: see text]