Prevalences of overweight, obesity, hyperglycaemia, hypertension and dyslipidaemia in the Gulf and Qatar
Reported, January 4, 2012
The increasing prevalence of diabetes mellitus, particularly type 2 diabetes mellitus, is well documented. Type 2 diabetes is currently estimated to account for over 90% of the global diabetes burden. Together with similar trends in other non-communicable diseases, it leads to risks not only for individuals, but for health systems, social systems, and state economies. This risk is in part to do with an anticipated relatively dramatic rise in countries with relatively young populations, and still developing economic infrastructure, as they undergo the predicted increases in prevalence of diabetes associated with changes in lifestyle and economic development, and population growth. Even when based on changes in population size and demography alone, the highest predicted future increases are expected in the International Diabetes Federation’s African region (estimated 98.1% increase 20102030), followed by the Middle East-North Africa region (estimated 93.9% increase 201020304). The Middle East-North Africa region already has some of the highest rates of diabetes in the world. The countries of the Co-operation Council for the Arab States of the Gulf (GCC) include those currently ranked 2, 3, 5,7 and 8 for diabetes prevalence among the 216 countries for which data are available.
This high prevalence in the GCC states is associated with higher prevalences of risk factors for type 2 diabetes in this region. The International Diabetes Federation suggests the following as risk factors for type 2 diabetes: age, obesity, family history, physical inactivity, race and ethnicity, and gestational diabetes. Of the modifiable risk factors, physical inactivity appears to have been surprisingly little studied in this region, although it is likely to be correlated with overweight and obesity, which have been relatively well studied.
We aimed to review the prevalence of overweight and obesity in the GCC region. We also aim to review the prevalence of potentially pre-diabetic hyperglycaemia (measured either as impaired fasting glycaemia, impaired glucose tolerance or raised random glucose). We also examined hypertension and dyslipidaemia, which are risk factors for adverse outcomes in people with diabetes.Diabetes is complicated by various micro- and macro-vascular conditions and people with metabolic syndrome a collective of obesity, insulin resistance, dyslipidaemia, hypertension and hyperglycaemia have a relatively higher prevalence of cardiovascular disease than those without. Due to the heterogeneity of studies identified on preliminary searching, there was no anticipated meta-analysis.
Forty-five studies (43 papers) relating to risk factors and their prevalence were identified for review. All papers identified were journal articles published between 1987 and 2010. Five studies were carried out (where reported) and/or published in the late 1980s, 23 in the 1990s, and 15 in the last 10 years. Studies of various Saudi, seven Kuwaiti, three Bahraini, eight Emirati, four Omani and one Qatari populations were included. All were cross-sectional studies; 23 of the general population, seven of primary care populations, four of schoolchildren, three of students, one of a young population, five of working populations. Women were exclusively studied in five cases, men in six. Sample size ranged from 215 to 25,337.
In addition to examining the prevalence of the particular risk factors in the GCC states, we were interested in the following:
Trends in prevalence across time;
Differences by country;
Trends in prevalence associated with age;
Sex differences;
Location (urban/rural) differences;
Prevalence in children.
Only in the cases of overweight and obesity, and hyperglycaemia were study numbers sufficient that reasonable conjecture regarding subgroups could be made. They are considered separately, for each risk factor, below.
Obesity/overweight
Thirty-three studies addressed the prevalence of overweight/obesity
Overweight and effect of date and country
The reported prevalence rates of overweight (BMI 25 to <30) in adults ranged from 26.348% in men, and 25.235% in women. Although higher values are there, they have been scaled down for/omitted from comparison as either the definition of overweight used included the typical definition of obesity, or the prevalence was given only by age group, allowing the possibility that similarly high figures were masked in the age-non-specific data of other studies. A lower value has also been omitted where the study population was particularly young. Within these ranges, the data were fairly even distributed between the limits, and reported sex-non-specific prevalences were also consistent with these figures. The data showed no obvious trends or anomalies by date or country, although the data from Oman (two studies, reporting combined overweight/obesity rates) suggest prevalence there may be relatively low.
Obesity and effect of date and country
The reported general prevalence rates of obesity (defined as BMI = 30) in adults ranged from 13.0537% in men, and 1649.15% in women (again a lower value has been omitted where the study population was particularly young54). As for the overweight data, the reported sex-non-specific data are consistent with these figures, and potentially excepting the Omani data, show no obvious trends or anomalies by date or country.
Obesity and overweight and age
Age as a potential predictor of prevalence of overweight/obesity was considered in eight studies (of adult populations), and the results were tested for significance in two cases. These latter studies demonstrated correlation between overweight/obesity and age, and a significantly higher mean BMI in a 4554-year age group versus a 5564-year age group.Similarly, all remaining studies indicated that prevalence increased with age to a threshold level (variably between 3040 and 5060 years (potentially younger in women) after which it began to fall, or fluctuate.
Obesity and overweight and sex
Most studies reported prevalence rates by sex, but only four tested for differences. Of these four, in all cases but one, BMI/prevalence of obesity and overweight was higher in women,and where overweight was higher in men, the combined prevalence of overweight/obesity remained higher in women. In the remaining studies, prevalence of obesity, and the combined prevalence of overweight/obesity was again always higher in women, although in some cases the difference was slight.
Obesity and overweight and residential environs
Six studies considered prevalence in urban versus rural populations. In three, mean BMI was found to be significantly higher in rural populations.In a further two studies, prevalence of both overweight and obesity were significantly lower in rural regions.This trend (with one subgroup exception female obesity) was also observed where significance of differences was unclear.
Obesity and overweight in national/expatriate populations
Only one study considered prevalences in national versus expatriate populations. This reported that the combined prevalence of obesity and overweight was higher in Kuwaitis versus non-Kuwaitis.
Obesity and overweight in children.In keeping with the association with age, prevalences in children/young people (<20 years) are lower than those in adult populations. However, there is a greater indication that prevalences in the younger populations are increasing. Single figure prevalences were reported until around 2000, and have not been observed since. The most recent reports (suggesting prevalences of combined overweight and obesity >30%) provide rates comparable to those in adults. Although less considered, there is again evidence for higher prevalences with increasing age in these relatively young populations, in urban areas and in girls.
Prevalence of overweight and obesity in the GCC region is high and the ages of those affected suggest it may be a relatively important factor in the growing diabetes burden in this region. Further study aimed at elucidating its relative contribution to the diabetes problem is desirable, but regardless the reviewed data are suggestive that implementation and enhancement of primary preventative strategies in particular would be useful in the management of type 2 diabetes in the GCC region. The current prevalences of hypertension and dyslipidaemia are unclear, but potentially relatively high compared to many other parts of the world. More comprehensive study of their prevalence is desirable, and standardization of definitions of these conditions will be important if further study is to be maximally useful. Primary preventative strategies may also be useful in managing these conditions.
Credits:Layla Alhyas, Ailsa McKay,Anjali Balasanthiran,and Azeem Majeed
More Information at:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3147233/?tool=pubmed