Active cigarette smoking, household passive smoke exposure, and the risk of developing pancreatic cancer

Objective. The objective of this study was to examine the association between active cigarette smoking, household passive smoke exposure, and pancreatic cancer risk using a prospective cohort design. Methods. Two cohorts were established in Washington County, Maryland in 1963 (n = 45,749) and 1975 (n = 48,172). The Washington County Cancer Registry was used to ascertain the occurrence of pancreatic cancer in the 1963 cohort from 1963-1978 and in the 1975 cohort from 1975-1994. Poisson regression was used to analyze the associations between active smoking and household passive smoke exposure and pancreatic cancer risk. Results. Current active smoking was associated with a two-fold increased risk of pancreatic cancer in both cohorts. Among never-smokers in each cohort, exposure to household passive smoke was not associated with an increased risk of pancreatic cancer, although the confidence limits were wide due to a small number of cases. Conclusions. This study further documents the approximate doubling of pancreatic cancer risk in current active smokers. Our results also indicate that household passive smoke exposure is not associated with pancreatic cancer risk, although our risk estimates lacked precision.