A pandemic refers to a disease that is rapidly increasing in frequency across many populations, over a wide geographical area (1). Put another way, it refers to the situation in which epidemics of the disease are occurring simultaneously in many countries. This is the case for diabetes, which has the dubious distinction of being one of the few chronic non-communicable diseases known to be increasing in all countries from which data are available, irrespective of the level of economic development (2). This is mirrored by a pandemic of people who are overweight or obese (3), the major risk factors for type 2 diabetes.
This chapter focuses on diabetes in adults (aged 20 years old and above), of which 85% to more than 95%, depending on the population, have type 2 diabetes (2, 4), which is thus the main contributor to the growing burden of diabetes. However, it is worth noting that, in children (<15 years old), the incidence of type 1 diabetes is also increasing, particularly in the youngest age groups, across the vast majority of countries from which good data are available (5). The reasons for this increase are unclear, although various environmental risk factors have been implicated (5).
This chapter aims to do the following:
◆ provide an overview of the prevalence and trends in diabetes in adults across the world and its contribution to mortality
◆ describe the broad determinants that underlie the increasing trends in diabetes in adults
◆ provide an introduction to variations by ethnicity in the prevalence of type 2 diabetes