Type 2 diabetes mellitus is among the fastest growing diseases in the world. The reported prevalence of T2D appears to differ among various ethnic groups. Although ethnic-related differences in lifestyle factors may account for some of the predisposition to diabetes in various ethnic groups, genetic factors may play a more determinant role.High prevalence rates of T2D have been reported in Middle-Eastern populations and these rates are considerably higher than those reported in Scandinavians.
The aims of this thesis were 1) to compare the clinical characteristics of T2D between immigrants from the Middle-East and Swedish subjects and to examine whether differences in the frequency of high risk genotypes in established T2D genes can explain differences in the clinical presentation of T2D between these 2 ethnic groups 2) to evaluate the effects of exercise on insulin sensitivity in sedentary, overweight Arabian and Swedish women with T2D.
The key findings were 1) Middle-Eastern immigrants with T2D have an earlier onset and stronger family history than Swedish patients. This, in turn, was associated with a more severe reduction in B .- cell function. Middle-Eastern immigrants with T2D had higher frequency of the TCF7L2 and PPARG genes compared with Scandinavian patients, 2) Despite no measurable increase in VO2max, overweight, sedentary Arabian and Swedish women with T2D were able to increase insulin sensitivity after a 6-month exercise intervention period.
Although this study provided some insight into the potential genetic factors explaining differences between Middle-Eastern and Swedish patients with T2D, larger studies are needed to explain whether unique patterns of T2D associated genes explain the high prevalence of T2D in Middle-East.