A Case-control Study Of The Risk Factors Associated With Thyroid Cancer In Zhejiang

Objective:1.To understand the risk factors of thyroid cancer in Zhejiang,and the distribution characteristics of these factors in different population,and further explore the etiology of thyroid cancer.2.To explore the difference between the risk factors of thyroid cancer in Zhejiang and the domestic and international,and to put forward the Countermeasures for prevention and control of thyroid cancer.Materials and methods:1.Contents and methods of investigation: according to the review of risk factors for thyroid cancer,the questionnaire of risk factors for thyroid cancer in Zhejiang province was prepared,using 1:1 matched case-control study.Contents: smoking,drinking and drinking tea,physical activities,eating habits,environmental exposure,disease and family history,mental and psychological factors,physical and reproductive history,physical condition,etc.The investigation environment is controlled by a one-to-one survey method.Data collection,entry and reporting by special investigators.2.Descriptive analysis: the survey data were recorded by Epidata3.1 software,and it was recorded by two perpon.The ArcGIS software is used to describe the area of the survey.On the general situation including smoking,drinking tea and alcohol,physical activity,diet,environmental exposure,disease history and family history,psychological factors and female physiological and reproductive history were described by analysis of the current situation,the constituent ratio of the four percentile,mean and standard deviation index.Of the patients and the control group on the social economic situation index balance test,measurement data using independent samples t test;two groups of count data were compared by chi square test or Fisher exact probability method;rank data using rank sum test,the above test were used SPSS statistical software to analyze and test level α=0.05.3.Single factor Logistic regression analysis: variables quantification,continuous variable grouping and numerical quantification of discontinuous variables.Conditional logistic regression model was used to take single case analysis of variables one by one and test level α=0.05.It is analyzed by SPSS software.The OR and its 95% confidence interval were used as the analysis index.4.Multivariate analysis: the single factor analysis showed statistically significant variables,and through the literature was screened for thyroid carcinoma.The variable of the multicollinearity diagnosis and interaction,more precise definition of exposure variables,selected after multicollinearity diagnosis and interaction analysis variables were analyzed by Logistic regression analysis,the regression method was used to select the variables,α=0.05 level test,the formation of the main effect model;in the control of hybrid and other risk factors,analyze the effect of variables one by using SPSS software.The OR and its 95%OR confidence interval were used as the analysis index.5.Literature analysis: according to a large number of literatures about thyroid cancer risk factors,thyroid cancer pathogenesis and thyroid cancer molecular epidemiology research,we screened thyroid cancer related risk factors.Results:1.The results of univariate analysis showed that gender,sleep quality,high intensity activity,nap,salt,meat and aquatic products,seafood,seaweed,kelp / pickled products,occupation exposure to ionizing radiation,trace elements and harmful gases,each year for X-ray examination,every year to accept CT examination,related diseases,family history of disease,self adjustment poor,long time depression,the relationship between BMI and thyroid cancer closely and contraception.2.The results of multivariate analysis showed that the meat and meat products is a risk factor of thyroid cancer,its OR=1.365(95%CI=1.160~1.607),receiving CT examination every year can increase the risk of thyroid cancer,its OR=1.632(95%CI=1.256~2.120),associated disease is a high risk factor for thyroid cancer,its OR=6.917(95%CI=4.684~0.213),poor self-regulation is the risk factor for thyroid cancer,its OR=2.429(95%CI=1.344~4.390),long time depression is a risk factor for thyroid cancer,its OR=1.711(95%CI=1.024~2.858),contraception is a risk factor for thyroid cancer,its OR=1.726(95%CI=1.161~2.567),and iodized salt is a protective factor for thyroid cancer,its OR=0.481(95%CI=0.323~0.718),aquaculture / seafood is the protective factor for thyroid cancer,its OR=0.743(95%CI=0.646~0.855),salted products are protective factors for thyroid cancer,its OR=0.772(95%CI=0.641~0.931).Conclusion:1.The occurrence of thyroid cancer is the result of multiple factors of genetic and environmental factors.2.The risk factors of thyroid cancer are mainly meat and products,CT examination every year,thyroid cancer related diseases,poor self-regulation,long time depression and contraception.3.The risk factors of thyroid cancer,meat and products,annual CT examination,thyroid cancer related diseases,poor self-regulation,long time mental depression and contraception were consistent with the findings of international and domestic studies.In this study,we found that iodized salt,aquatic / seafood and salted products are the protective factors for thyroid cancer,which are not consistent with the domestic and international research results.4.The harm of thyroid cancer can not be ignored.We should implement "three level prevention" as early as possible,especially for thyroid cancer risk factors,and also need comprehensive and timely prevention and control.