ABSTRACT
Objective@#To investigate the combined impact of lifestyle factors on stomach cancer risk.@*Methods@#We analyzed the data from the Shanghai Men's Health Study (SMHS) (2002-2013). The SMHS was conducted in eight neighborhood communities of urban Shanghai. From 2002 through June 2006, 61 480 residents aged 40 to 74 years old with no history of cancer were recruited. Failure time was the date of stomach cancer incidence, death or date of the last follow-up (December 31, 2013). The first two in-person follow-up surveys were conducted in 2004-2008, and 2008-2011, respectively. Using data on lifestyle, the healthy lifestyle index (HLI) was developed. The following lifestyle factors were included: smoking, alcohol consumption, diet habit, overweighted and physical activity. Cox proportional hazard models were used to evaluate the association of stomach cancer risk with lifestyle factors and HLI.@*Results@#Over 9.28 years' follow-up, 477 incident cases of stomach cancer were identified from 59 503 study participants. Participants with zero, one, two, three, four, and five favorable lifestyle behaviors accounted for 3.44% (n=2 045), 18.14% (n=10 793), 33.68% (n=20 041), 29.43% (n=17 511), 12.82% (n=7 627), and 2.50% (n=1 486), respectively. Among all the five lifestyle factors, smoking and alcohol use were significantly related to stomach cancer risk. The relative risk of stomach cancer was 0.71 (95%CI: 0.57-0.87) for those who never smoked or quitted smoking for no less than 10 years and 0.70 (95%CI: 0.55-0.90) for those who consumed alcohol no more than 14 drinks per week. For each increment of healthy lifestyle index, the relative risk of stomach cancer was 0.86 (95%CI: 0.79-0.95). Compared to men with none or one healthy lifestyle factor, the relative risk for those with four or five was 0.62 (95%CI: 0.46-0.83). When we rebuilt HLI using more categories of each lifestyle factors, the HLI ranged from 0 to 11. For each point increase, the relative risk of stomach cancer was 0.93 (95%CI: 0.89-0.97). Compared those with 0 to 3 points, the relative risk of those with 8 to 11 points was 0.64 (95%CI: 0.47-0.87).@*Conclusion@#In the SMHS, only a small proportion of men adhered to all the five healthy lifestyle factors. Compared to those with none or one healthy lifestyle behaviors, those with five may prevent about 1/3 stomach cancer incidence and the HLI was inversely associated with stomach cancer risk.
ABSTRACT
Objective To evaluate the factors influencing the reproducibility and validity of food group intakes measured by a food frequency questionnaire (FFQ) for Chinese men. Methods A total of 214 adult men were randomly selected from the Shanghai Men Health Study (SMHS), an ongoing cohort study conducted in urban Shanghai. Each subject who had completed the first FFQ survey at recruitment took 24-hour dietary recall (24-HDR) surveys which were conducted once a month for 12 consecutive months and a second FFQ at the end of the study. Two FFQs were administered approximately 1.2 years apart. The food items listed in FFQ and obtained from 24-HDR were categorized into 11 food groups. The factors influencing the reproducibility of the FFQ was assessed by comparing the Pearson correlation of intake levels from the two FFQs, while the factors influencing the validity was evaluated by comparing intake levels from the second FFQ with the multiple 24-HDRs. Results A total of 195 men completed all 12 times of 24-HDR and twice FFQ surveys. The median Pearson correlation coefficients of the food groups between the two FFQs in older vs younger age group were 0.62 vs 0.50;in higher vs lower education level group were 0.58 vs 0.50;in higher vs lower income group were 0.51 vs 0.50;in higher vs lower BMI group were 0.50 vs 0.49. The median Pearson correlation coefficients of the food groups between the second FFQ and 24-HDRs in older vs younger age group were 0.61 vs 0.45;in higher vs lower education level group were 0.49 vs 0.47;in higher vs lower income group were 0.43 vs 0.57;in higher vs lower BMI group were 0.48 vs 0.51. Conclusions Age is the main factor influencing the reproducibility of the food group intakes by a FFQ used in the SMHS, while the factors influencing the validity are age and family income.