Prevalence and Incidence Rate of Diabetes, Pre-diabetes, Uncontrolled Diabetes, and Their Predictors in the Adult Population in Southeastern Iran: Findings From KERCADR Study

Abstract

Background: Diabetes mellitus is among the most serious health challenges worldwide. We assessed the prevalence of pre-diabetes (pre-DM) and diabetes (DM), the effectiveness of diabetes management, the 5-year incidence rate, and associated variables in the adult population in southeastern Iran. Methods: In a random cluster household survey (2014-2018), 9,959 adult individuals aged 15-80 years were assessed for coronary artery disease risk factors, including diabetes mellitus in Kerman (KERCADRS, phase 2). Among these people, 2,820 persons had also participated in phase 1 of the study 5 years earlier (2009-2011). Univariable and multivariable survey logistic regression models were used to identify the potential predictors of diabetes and pre-diabetes. Results: The prevalence of pre-DM was 12% (males 13.2% vs. females 11.1%), steadily increasing from 7.1% in the 15-24 years group to 18.4% in the 55-64 years group. The prevalence of DM was 10.2% (male and female, 7.9 and 10.8%, respectively), of which 1.9% were undiagnosed. DM was diagnosed in 10.6% of educated and 15.1% of illiterate people. The prevalence of diagnosed DM was lower in smokers (5.2 vs. 8.7%) and dependent opium users (5.4 vs. 8.8%). The prevalence of uncontrolled DM (HbA1c > 7%) was 48.8%, increasing with age. The frequency of uncontrolled DM among people without and with treatment was 32 and 55.9%, respectively. Illiterate people had worse uncontrolled DM (55.6 vs. 39.6%). The 5-year incidence rate (persons/100 person-years) was 1.5 for pre-DM and 1.2 for DM, respectively. The lowest and the highest incidence rate of DM belonged to the 15-34 years old group (0.5) and dependent opium users (2.4). The incidence rate was found to have a direct relationship with BMI and a reverse relationship with physical activity. Conclusion: Pre-DM and DM affected 22.2% of the population. One-third of patients with diabetes had undiagnosed DM, and in 55.9% of people with diagnosed DM, treatment had been ineffective. Appropriate health interventions are needed to reduce the prevalence and health consequences of diabetes in the region.

Keywords: HbA1c; Iran; diabetes mellitus; incidence rate; pre-diabetes; uncontrolled diabetes; undiagnosed diabetes.

Figure 1

The flow chart of people participated in both phases of the study.

Figure 2

The prevalence of pre-diabetes (A,B) and diabetes (C,D) in KERCADRS by sex and age groups. Total participants = 9,959 in phase 2 and 5,900 in phase 1. The data of phase 1 were used here for comparison and are extracted from our paper published previously (20). *P < 0.05, **P < 0.01, ***P < 0.001 compared to phase 1.

Figure 3

The prevalence of undiagnosed DM (A,B) and uncontrolled DM in the diagnosed diabetic participants (C,D) in the study (KERCADRS) by sex and age groups. Total participants were 9,957 in phase 2 and 5,900 in phase 1. The data of phase 1 were used here for comparison and are extracted from our paper published previously (20). **P < 0.01 compared to phase 1.