A
Population-based Case-Control Study Juan Miguel Barros-Dios, María
Amparo Barreiro, Alberto Ruano-Ravina, and Adolfo Figueiras (May
2002)
The authors conducted a population-based case-control study in northwest
Spain to determine the risk of lung cancer associated with exposure
to residential radon. The study covered a total of 163 subjects with
incident lung cancer and a population sample of 241 cancer-free subjects
since 1992 1994.
Odds ratios for radon were estimated using logistic regression adjusted
for sex, age, lifetime tobacco use, family history, and habitat.
The adjusted odds ratios for the second, third, and fourth quartiles
of radon (breakpoints: 37.0, 55.2, and 148.0 Bq/m 3) were 2.73 (95%
confidence interval (CI): 1.12, 5.48), 2.48 (95% CI:1.29, 6.79),
and 2.96 (95% CI: 1.29, 6.79), respectively.
An
additive synergic effect between radon and tobacco was found. The
results from this study suggest that, even at concentrations far
below official guideline levels, radon may lead to a 2.5-fold rise
in the risk of lung cancer. Furthermore, the synergy found between
smoking and radon may prove useful when it comes to drafting public
health recommendations. AmJEpidemiol 2002;156:548–55.