Epidemiologic Study On The Risk Factors Of Lung Cancer

[Objectives]To study the main risk factors and etiological clues of lung cancer in Fujian Province and provide the scientific basis for controlling and preventing lung cancer.[Methods]A molecular epidemiologic approach and a case-control design were used for analyses. The 831 subjects of the study were all Fujian residents and had lived in Fujian for over 10 years. The 400 patients from The First Affiliated Hospital of Fujian Medical University, Fujian Union Hospital and Fuzhou General Hospital were newly diagnosed with primary lung cancer according to the bronchoscope and pathologic diagnoses and were able to cooperate with the interviewers. A structured questionnaire was administered face to face to all subjects. A sample of 5ml blood was collected from each participant. The 431 cancer-free controls were randomly recruited from the individuals that visited the same hospitals as the cases which had no family history of cancer and were frequency-matched to the cases on age(+5y), sex and residential area. Saliva was collected from controls by Oragene Assembler, and preserved strictly in accordance to the operational requirements. EpiData 3.0 was used to collect and SPSS 13.0 for windows to analyze the data.[Results]1. The risk factors of lung cancer in Fujian province included: smoke and second-hand smoke, environmental exposures in neighborhood, unseparation of kitchen and bedroom, coal using, heavy smoke from cooking, irritant smell after decoration, edible animal oil, frequent intake of salty vegetable, alcohol drinking (including white wine and wheat wine), history of pulmonary tuberculosis, history of agricultural chemical using, depression and BMI<18.5.2. The protective factors of lung cancer in Fujian province included: frequent intake of fresh vegetables, eggs and milk and milk product, light tea drinking, exercise (including①physical activities;②walking ), BMI≥25.3. The same risk factors of male and female lung cancer were second-hand smoking (both at home and in public), edible animal oil frequent intake of salty vegetables and agricultural chemical using. Besides, the risk factors of male lung cancer also included smoking, alcohol drinking, history of pulmonary tuberculosis, coal using, irritant smell after decoration, environmental exposures in neighborhood and BMI<18.5. The risk factors of female lung cancer included heavy smoke from cooking and second-hand smoking.4. The same protective factors of male and female lung cancer were frequent intake of milk(and milk product) ,eggs and exercise. Besides, the protective factors of male lung cancer also included frequent intake of fresh vegetables and BMI≥25. The protective factors of female lung cancer included frequent intake of fresh seafood and tea drinking.5. Second-hand smoking at workplace was the joint risk factor of lung squamous cell carcinoma and lung adenocarcinoma. The risk factors of lung adenocarcinoma included: smoking≥30 pack per year, history of pulmonary tuberculosis and frequent intake of animal oil. The risk factors of lung adenocarcinoma also included: second-hand smoking at home and first level family cancer history. Frequent intake of milk and milk product was a protective factor of lung squamous cell carcinoma; tea drinking and walking were both protective factors of lung adenocarcinoma.[Conclusions]1. Air pollution, smoking, second-hand smoking , bad diet habits and ill-lifestyles were the risk factors of lung cancer.2. Same and different risk or protective factors were due to the differences between genders and pathologic types.3. We realized that in order to prevent lung cancer in Fujian , we had to forbid smoking in public through administrative legislation, reduce alcohol, improve outdoor air quality, and have more eggs, fresh vegetables, milk and milk product. Besides, more tea drinking and moderate exercise would help.