The Association Between Food Group,nutrition,dietary Pattern And The Risk Of Lung Cancer

Objective: 1 Numerous meta-analyses have identified dietary risk factors for lung cancer,however,some of the findings are inconsistent.Thus,we evaluated and summarized the strength and validity of the reported findings.2 To assess the association between dietary factors(including food group,nutrition,dietary scores,dietary patterns)and risk of lung cancer in Shenyang.Methods: 1 This umbrella review was registered with PROSPERO(number CRD 42020199776).We searched Pub Med,Embase,and Web of Science for papers published until 10 July 2020 and screened the reference list for relevant meta-analyses.We assessed statistical significance of the random-effect summary estimate,the largest study in a metaanalysis,the number of cancer cases,heterogeneity between studies,95% prediction intervals(95% PI),small study effects,and excess significance bias.We then classified evidence as convincing,highly suggestive,suggestive,or weak.2 In this study,the cases were from the Department of Oncology of Shengjing Hospital in Shenyang,and the controls were from ethnic cohort in northeastern region.Cases and controls were matched using the propensity score matching method.Dietary information was collected by a valid semi-quantitative food frequency questionnaire.Two priori dietary scores were calculated according to the corresponding criteria,posteriori dietary patterns were derived using exploratory factor analysis.The correlations between dietary factors and lung cancer were analyzed by conditional Logistic regression model.Results: 1 Umbrella review 1.1 Thirty-one articles,including 81 meta-analyses of observational studies covering a wide range of food,nutrition,and dietary patterns,were identified from the database search.1.2 Based on AMSTAR,all meta-analyses were considered to provide evidence of at least moderate quality.1.3 Among 81 associations,44(54%)were significant at a P<0.05 threshold,and 17(21%)at a P<0.001 threshold under the random effects model.In addition,3(4%)metaanalyses were significant at a P<10-6 threshold.1.4 Large heterogeneity(I2 ?50%)was observed in 61% of the meta-analyses,9% of studies suffered from small-study effects,and one-half of the studies had excess significance.1.5 The association of nut consumption with lung cancer was supported by convincing evidence.In addition,consumption of red meat and cholesterol was associated with an increased risk of lung cancer(suggestive evidence).Consumption of another six foods(vegetables,fruits,cruciferous vegetables,carrots,ginseng,and tea)and four nutrients(?-carotene,dietary ?-cryptoxanthin,dietary total carotenoids,and dietary folate),as well as a healthy dietary pattern was associated with a decreased risk of lung cancer(suggestive evidence).2 The association between food groups,nutrition and risk of lung cancer 2.1 A total of 686 controls and 343 lung cancer patients were successfully matched by propensity score matching method.Age,sex,education level,smoking status,drinking status,family history of cancer,body mass index,marital status and total energy between the two groups were not significantly different.2.2 After matching and adjusting for residence,region,income and other food groups,the risk of lung cancer was increased by the intake of red meat.Compared with the lowest quartile,the odds ratio(OR)and 95% confidence interval(CI)of the highest quartile were 1.22(1.05-2.12).The result was statistically significant.The intake of vegetables could reduce the risk of lung cancer.Compared with the lowest quartile,the OR and 95% CI of the highest quartile were 0.89(0.66-0.97).No associations were found between the other food groups and lung cancer.After matching and adjusting for residence,region and income,the consumption of total dietary fiber,beta-carotene,vitamin C,and potassium could reduce the risk of lung cancer,compared with the lowest quartile,the ORs(95%CIs)of the highest quartile were 0.32(0.15-0.66),0.70(0.59-0.87),0.82(0.52-0.99),0.67(0.61-0.86),respectively.3 The association between dietary patterns and risk of lung cancer.3.1 CHEI scores were not associated with the risk of lung cancer,compared with the lowest quartile,the ORs(95% CIs)of the 2,3,and 4 quartiles were 0.86(0.51-1.44),0.86(0.51-1.45),0.65(0.35-1.21),respectively after matching and adjusting for residence,region and income.CDQI scores were associated with a reduced risk of lung cancer,compared with the first quartile,the fourth quartile reduced the risk of lung cancer by 26% significantly(95% CI: 0.54-0.99).3.3 Factor analysis revealed three dietary patterns in Shenyang: healthy dietary pattern,meat dietary pattern,and egg-milk-vegetables dietary pattern.The healthy diet pattern was negatively correlated with the incidence of lung cancer.In the final adjusted model,compared with the first quartile,OR(95% CI)of the fourth quartile was 0.68(0.56-0.88).The meat pattern was not associated with the risk of lung cancer,compared with the first quartile,the ORs(95% CIs)of the 2,3,and 4 quartiles were 0.89(0.51-1.53),0.95(0.43-2.09),1.10(0.49-2.47).The egg-milk-vegetables dietary pattern was not associated with the risk of lung cancer,compared with the first quartile,the ORs(95% CIs)of the 2,3,and 4 quartiles were 0.98(0.81-1.11),0.94(0.56-1.30),0.91(0.51-1.38).Conclusion: 1 Despite a number of meta-analyses exploring the association between dietary factors and the incidence of lung cancer,convincing evidence only exists for nut consumption,and associations between a number of dietary factors and incidence of lung cancer are needed further to explore.2 Dietary factors that associated with a reduced risk of lung cancer in the Shenyang include vegetables,dietary fiber,beta-carotene,vitamin C,and potassium.Intake of red meat was associated with an increased risk of lung cancer.More evidence was needed to identified the associations.3.1 After adjusting for covariable,CHEI scores were not correlated with the incidence of lung cancer.CDQI scores were negatively correlated with the incidence of lung cancer.It was suggested that a balanced diet could reduce the risk of lung cancer,but extrapolation should be cautious,and more large studies are needed to explore the correlations.3.2 After matching and adjusting for residence,region,income and other dietary patterns,it was found that healthy dietary pattern was negatively correlated with the incidence of lung cancer,while meat dietary pattern and egg-milk-vegetables pattern were not correlated with the incidence of lung cancer.