Dongfeng-Tongji cohort: methodology of the survey and the characteristics of baseline and initial population of follow-up program

Abstract

To explore the effects of related environment, occupational, lifestyle, genetic factors as well as their interactions on the etiology of major chronic diseases in an occupational population. Dongfeng-Tongji cohort (DFTJ cohort), one of the large prospective cohort studies with biobank. Baseline study was conducted in Shiyan city, Hubei province from 2008 to 2009. This cohort study included questionnaire, physical examination and tests on blood samples. Dongfeng-Tongji cohort was followed up every 5 years and the first follow-up program was completed, from April to October in 2013. During the first follow-up period in 2013, questionnaire, physical examination, clinical and blood sample tests were conducted again. 27 009 retired participants with mean age of 63.6 years including 44.6% males, were recruited in this study. In the first follow-up program in 2013, among 38 295 subjects (44.7% males), 40.5% of them received diploma from high school or above. Prevalence rates of current regular smokers were 33.6% in men and 2.0% in women and the rates on current alcohol drinkers were 39.9% in men and 10.6% in women. The prevalence rates on self-reported hypertension, hypercholesterolemia, diabetes mellitus, coronary heart disease, stroke, chronic bronchitis, and asthma were 41.1%, 24.3%, 13.9%, 16.7%, 5.1%, 12.7% and 4.0%, respectively. The self-reported prevalence of hypertension and stroke in males was higher than that in females. 25 978 individuals who were involved in the baseline database successfully completed the followed up program in 2013, with the follow-up rate as 96.2%. The DFTJ cohort study offered us an opportunity to explore the effects of environmental, genetic, as well as their interactions with major chronic diseases in a Chinese occupational population.