Population Attributable Risk Estimation Of Risk Factors For Lung Cancer In Urban Shanghai

[Objective] To provide evidence for decision-making on cancer prevention through population attributable risk analysis of lifestyle-related factors on lung cancer among men and women in urban Shanghai.[Methods] Two large population-based cohorts, the Shanghai Women’s Health Study (SWHS) and Shanghai Men’s Health Study (SMHS), were established in urban Shanghai during1997-2000and2002-2006. A total of74,942female residents aged40to70were involved in the SWHS, and61,500male residents aged40to74were involved in the SMHS. Information on demographic characteristics, smoking, alcohol dringking, tea drinking, diet, physical activity, chronic diseases, anthropometric measures, and menstrual and reproductive history and so on were collected at baseline. By the end of2009,426incident cases of male lung cancer,474incident cases of female lung cancer were identified in the two cohorts, respectively. Diagnosis of cancer was confirmed by medical history, clinical imaging examination or pathological information. Person-years of each participant were calculated from the date of the baseline interview to the dates of cancer diagnosis, death, lost follow-up or December31,2009. Cox proportional hazard model was used to estimate the adjusted hazard ratios (HRs) and their95%confidence intervals (CIs) of lifestyle factors with lung cancer. Population attributable risks (PARs) and their95%CI were caluculated based on the confounding adjusted harzard ratios and exposures of corresponding risk factors among cases in the two cohorts.[Results] The results of multivariate analysis of data showed that smoking, alcohol drinking, tea drinking, body mass index, fruit intake, chronic bronchitis, asthma and family history of lung cancer were associated with the risk of male lung cancer. The adjusted population attributable risks (PARs) of some major risk factors were estimated.64%of male lung cancer was due to smoking,18%of male lung cancer was due to alcohol drinking, low fruit intake was responsible for26%of male lung cancer and low body mass index was responsible for19%of male lung cancer. The PARs of chronic bronchitis, asthma and family history for male lung cancer were10%,1%and3%, respectively.5%of male lung cancer among non-smokers was due to asthma,10%of male lung cancer was due to chronic bronchitis among smokers. It was estimated that smoking, asthma, cooking fuels and lifetime duration of exposure to physio-estrogens were associated with female lung cancer. The PARs of smoking, asthma and cooking fuels for female lung cancer was7%,2%,25%, respectively. Short duration of exposure to physio-estrogens was responsible for18%of female lung cancer incidence. Subgroup analysis among non-smoking women was also conducted. The PARs of cooking fuels, asthma and passive smoking at work place for female lung cancers were21%,4%and3%, respectively.17%of female lung cancer incidence among non-smokers was due to short duration of exposure to physio-estrogens.[Conclusions] Incidence of male lung cancer in urban Shanghai was largely due to smoking, alcohol drinking, tea drinking, low body mass index and low fruit intake. Lung cancer incidence among women was largely due to duration of exposure to physio-estrogens, smoking, asthma and cooking fuels which were accounted for a number proportions of development of female lung cancer.