Systematic review and meta-analysis of residential radon and lung cancer in never-smokers

Abstract

BackgroundGlobally, radon is the leading risk factor for lung cancer in never-smokers (LCINS). In this study, we systematically reviewed and meta-analysed the evidence of the risk of LCINS associated with residential radon exposure.MethodsMedline and Embase databases were searched using predefined inclusion and exclusion criteria to identify relevant studies published from 1 January 1990 to 5 March 2020 focused on never-smokers. We identified four pooled collaborative studies (incorporating data from 24 case–control studies), one case–control study and one cohort study for systematic review. Meta-analysis was performed on the results of the four pooled studies due to different measures of effect and outcome reported in the cohort study and insufficient information reported for the case–control study. In a post hoc analysis, the corresponding risk for ever-smokers was also examined.ResultsRisk estimates of lung cancer from residential radon exposure were pooled in the meta-analysis for 2341 never-smoker cases, 8967 never-smoker controls, 9937 ever-smoker cases and 12 463 ever-smoker controls. Adjusted excess relative risks (aERRs) per 100 Bq·m−3 of radon level were 0.15 (95% CI 0.06–0.25) for never-smokers and 0.09 (95% CI 0.03–0.16) for ever-smokers, and the difference between them was statistically insignificant (p=0.32). The aERR per 100 Bq·m−3was higher for men (0.46; 95% CI 0.15–0.76) than for women (0.09; 95% CI −0.02–0.20) among never-smokers (p=0.027).ConclusionThis study provided quantified risk estimates for lung cancer from residential radon exposure among both never-smokers and ever-smokers. Among never-smokers in radon-prone areas, men were at higher risk of lung cancer than women.

Lung cancer among women — identifying risk factors

“…One of the serious carcinogens is naturally occurring radon, which is considered as a second lung cancer risk factor after smoking. The large analysis of the studies conducted in never-smokers confirmed the relationship between residual radon and lung cancer, which was higher in never than in ever smokers and among man than women [49]. However, the synergistic effect of radon with smoking was pointed in this review leading to the conclusion, that, for both sexes, people living in the radon-prone area (> 100 Bq/m 3 ) should be considered as a high-risk group.…”

Association of Smoking With Patient Characteristics and Outcomes in Small Cell Lung Carcinoma, 2011-2018

“…Radon exposure has been considered a risk factor for SCLC. Torres-Durán et al 20 and others 40 , 41 , 42 reported higher levels of residential radon exposure among never-smoker patients with SCLC. However, the causal relationship between radon and SCLC remains to be determined.…”

Relationships among Indoor Radon, Earthquake Magnitude Data and Lung Cancer Risks in a Residential Building of an Apulian Town (Southern Italy)

“…Radon-attributable lung cancer deaths for all 66 countries totaled 226,057 in 2012 and represented a median of 3.0% of total cancer deaths [77]. Recently, multiple published studies have measured the risk of developing lung cancer following residential or occupational radon exposure in various regions of the world, as well as the synergistic effect of cigarette smoking and the effect in never-smokers [8][9][10]73,[77][78][79][80][81] as well as analyzing the histological types of lung cancer [82].…”