Evolving Trends in the Epidemiology, Risk Factors, and Prevention of Type 2 Diabetes: A Review

Currently, the global prevalence of diabetes is 8.8%. This figure is expected to increase worldwide, with the largest changes projected to occur in low- and middle-income countries. The aging of the world's population and substantial increases in obesity have contributed to the rise in diabetes. Global shifts in lifestyles have led to the adoption of unhealthy behaviours such as physical inactivity and poorer-quality diets. Correspondingly, diabetes is a rapidly-increasing problem in higher- as well as lower-income countries. In Canada, the prevalence of diabetes increased approximately 70% in the past decade. Although diabetes-related mortality rates have decreased in Canada, the number of people affected by diabetes has continued to grow because of a surge in the number of new diabetes cases. Non-European ethnic groups and individuals of lower socioeconomic status have been disproportionately affected by diabetes and its risk factors. Clinical trials have proven efficacy in reducing the onset of diabetes in high-risk populations through diet and physical activity interventions. However, these findings have not been broadly implemented into the Canadian health care context. In this article we review the evolving epidemiology of type 2 diabetes, with regard to trends in occurrence rates and prevalence; the role of risk factors including those related to ethnicity, obesity, diet, physical activity, socioeconomic status, prediabetes, and pregnancy; and the identification of critical windows for lifestyle intervention. Identifying high-risk populations and addressing the upstream determinants and risk factors of diabetes might prove to be effective diabetes prevention strategies to curb the current diabetes epidemic.