The Association of Visibility and Adenocarcinoma Lung Cancer in Southern Taiwan

Abstract

Background/Aim Studies on association between lung cancer and long-term exposure to air pollution are limited due to the unavailability of air pollution data. The study aims to assess association of visibility, a proxy indicator of long-term air pollution exposure, with adenocarcinoma lung cancer. Methods Our study area is in southern Taiwan, an industrial area with 2.7 million people in 5.7 thousand km². Annual lung cancer incidence data with the ICD-O-3 codes from C34.0-C34.9 were obtained from Taiwan Cancer Registry (TCR) from 1997 to 2018. Age-adjusted incidence of lung cancers were standardized by the WHO 2000 world standard population. Hourly atmospheric visibility data from 1961 to 2022 were obtained from Taiwan Central Weather Bureau. 30-years moving averages were then calculated from 1967 onward to represent long-term visibility in the study area. Linear regression models were employed to estimate associations of 30-years averaging visibility annual age-adjusted lung cancers incidence for both adenocarcinoma and non-adenocarcinoma from 1997 to 2018. Results From 1997 to 2018, southern Taiwan's adenocarcinoma lung cancer incidence increased from 8.93 to 25.81 per 100,000 population, while non-adenocarcinoma incidence decreased from 14.61 to 10.41 per 100,000 population. The 30-years averaged visibility in the study area declined from 14.90 km to 7.65 km in the same period. Reducing visibility is significantly associated adenocarcinoma lung cancer, with a 2.43% (95% confidence interval [CI]: 2.77-2.11, adjusted R2 value: 0.92) increase in incidence by 1 km decrease in visibility during this period. Such associations exist for both females and males with increasing incidence of 2.57% (95% CI: 2.92-2.22, adj R2: 0.92) and 2.32% (95% CI: 2.69-1.95, adj R2: 0.89) by 1 km visibility reduction, respectively. By contrast, visibility reduction was not associated with increased in non-adenocarcinoma incidence. Conclusions Long-term visibility reduction is associated with increase in adenocarcinoma lung cancer incidence but not with non-adnocarcinoma.