Prevalence of metabolic syndrome and prediction of diabetes using IDF versus ATPIII criteria in a Middle East population

Abstract

This study investigates the prevalence and predictive value of metabolic syndrome in Abu Dhabi, using data from the population-based, programme, ‘Weqaya’. The Weqaya screen included family history of cardiovascular disease (CVD), CVD risk factors, random blood glucose (RBG) and HbA1c. Those not previously diabetic but at high risk of diabetes (RBG ≥ 11.1 mmol/l or HbA1c ≥ 6.1%) and randomly selected normal subjects were followed-up with fasting glucose, oral glucose tolerance test (OGTT), HbA1c and fasting triglycerides. In 760 subjects, 325 (42.8%) were male with a mean age of 41.9 years (SD 13.8). Using World Health Organisation (WHO) criteria, 149 (20.2%) were newly diagnosed diabetics. Using International Diabetes Foundation (IDF) and Adult Treatment Panel III (ATPIII) criteria, metabolic syndrome was present in 29.0% vs. 31.5% of non-diabetics, 63.4% vs. 64.2% with impaired glucose handling and 78.6% vs. 79.8% with new-onset diabetes using OGTT (P < .001). IDF criteria better predicted pre-diabetes and diabetes (OR 3.4 P < .001; OR 6.4 P < .001, respectively); ATPIII criteria better predicted high CVD risk scores (OR 13.6 P < .001). Whilst IDF and APTIII definitions provide similar prevalence rates, they differentially predict prediabetes, diabetes and CVD. This ongoing study will enable the longitudinal investigation of the development of diabetes and cardiovascular events in this population.

Introduction

Despite its relatively young population (with a median age of 19 years in Nationals), population health data from Abu Dhabi, which is the largest of the seven emirates in the United Arab Emirates (UAE), shows that diseases of the circulatory system are the leading cause of mortality in the Emirate, accounting for over 24% of deaths in 2009 [1]. In 2005, the WHO reported that the UAE had the second highest prevalence of diabetes [2] in the world and this was re-confirmed by The International Diabetes Atlas. [3] A recently updated version of the International Diabetes Atlas revealed that the prevalence rate of diabetes in the UAE had shifted to 10th highest worldwide [4].

In response to this, and in line with recent recommendations from United Nations, [5] World Health Organisation [6], World Economic Forum [7] and Institute of Medicine [8], the Health Authority Abu Dhabi created the Weqaya Cardiovascular Disease Screening Programme. In the initial phase of the Weqaya Programme, the UAE National population, over the age of 18, was screened for CVD risk factors including diabetes [9]. A subset of this population who were fond to be at higher risk of having diabetes was further investigated for metabolic syndrome.

Although no population-based studies looking into the prevalence of metabolic syndrome have been conducted in the UAE, a study on overweight and obese individuals in Abu Dhabi aged 18–50 years showed a very high prevalence of 40.5% using criteria from the International Diabetes Federation (IDF) [10], [11]. Another study performed in the neighbouring country of Qatar, comparing the difference in prevalence of metabolic syndrome found that IDF criteria gave a higher rate of metabolic syndrome of 33.7% (versus 26.5% according to Adult Treatment Panel III (ATP III) criteria) [12], [13]. A second study conducted in Iran, estimated the prevalence of metabolic syndrome to be 34.7% based on ATPIII criteria and 37.4% based on IDF criteria [14]. In addition, this study provided an ethnic-specific optimal cutoff point for waist circumference in the Middle East [14].

Several other studies conducted in Middle Eastern populations suggest even higher rates of metabolic syndrome with rates in excess of 40% in the normal population [15], [16], [17], however neither of these studies, nor those mentioned above, describe the prevalence of metabolic syndrome and its association with diabetes. Furthermore, there is variation according to different methodologies used in these studies, in particular the differing criteria for defining metabolic syndrome according to WHO, ATPIII (NCEP) and IDF. [11], [13], [18] The IDF criteria were developed with a view to accounting for ethnic differences in body fat composition. However, due to the lack of available data on GCC and other Middle Eastern populations, the IDF criteria recommend European cutoffs for waist circumference for this population.

This study seeks to investigate the impact of utilising different criteria on the prevalence and predictive value of metabolic syndrome in Abu Dhabi, using data from the population-based, cardiovascular screening programme, ‘Weqaya’.