Isfahan Diabetes Cohort Study: An Overview on the Results in the First-Degree Relatives of Type 2 Diabetic Patients

Background: There is a lack of information on the probabilities to transit from normal glucose tolerance (NGT) to different pre-diabetic states and from these states to T2DM. The objective of our study is to estimate the risk equations and to quantify the influence of single or combined risk factors on these transition probabilities.Methods: This is a prospective cohort study that has been started since 2003 and is being continued. Three thousands first-degree relatives of diabetic patients (706 men, 2294 women) aged35-55 years were registered and enrolled into the study from October 2003 to August 2012. The cohort was closed in 2012 with 3000 participants and the participants have been followed up. It is plannned to continue the study for 30 years. Participants have been categorized into 3 groups of normoglycemic, pre-diabetic and diabetic subjects by American Diabetes Association (ADA) criteria according to Oral Glucose Tolerance Test (OGTT). In normoglycemic, Normal Glucose Tolerant (NGT), and pre-diabetic groups, dietary and physical activity assessments, anthropometric measures, determination of glycemic and lipid profiles, liver function tests, CBC, uric acid, and blood pressure measurements were performed and the related data were collected at the beginning of the study and have been repeated every three years in NGT, and annually in prediabetic groups. In 14 sub-population of these participants, 14 clinical trial were done to find a way to prevent the diabetes and the results hve been published and would not be discussed here. Results: In 2012, the prevalence of diabetes was 9.35%, and of prediabetes was 39.3% in the first-degree relatives of T2DM. In 2019, it is 19.5% and 39%, respectively. The incidence of diabetes in NGT was 9 event per 1000 person years and the incidence of diabetes in prediabetic participants was 35 event per 1000 person years. In comparison with general population, energy consumption was higher and physical activity was lower in the first-degree relatives of diabetic people. Cardiometabolic risk factors such as hypertension, hyperlipidemia and overweight and obesity were higher than general population (data have already been published). Conclusion: The prevalence and incidence of diabetes and cardiometabolic risk factors are higher in the first degree relatives of type 2 diabetic patients compared to the gereral population inspite of giving education to all of them at enrollment. It seems that a practical community based social networking education in changing lifestyle at work, home and society for everybody especially for the first degree relatives of T2DM has to be done to as soon as possible to prevent health and economic burden of diabetes.