An 'alarming' rise in obesity has contributed to a dramatic increase in the prevalence of diabetes in the U.S, according to a new study published in Annals of Internal Medicine. Researchers examined the prevalence of diabetes, prediabetes, and glycemic control in 43,439 adults followed by the National Health and Nutrition Examination Survey (NHANES) from 1988 to 1994 and 1999 to 2010. Diabetes was either self-reported (previously diagnosed) or defined by a single HbA1c level of 6.5 percent or greater or a fasting plasma glucose level of 7 mmol/L or greater.
The survey showed that demographic characteristics of the U.S. population remained relatively stable over the study periods, with the exception of changes in the racial or ethnic makeup of the population. The prevalence of total confirmed diabetes (diagnosed or undiagnosed) rose from 5.5 percent in 1988 to 1994, 7.6 percent in 1999 to 2004, and 9.3 percent in 2005 to 2010. Glycemic control in people with diagnosed diabetes improved, yet a sizeable proportion of people with diagnosed diabetes still had hemoglobin A1c levels greater than 7 percent. The proportion of diabetes cases that are undiagnosed decreased over the study years, which the authors speculate is likely due to the improvements in screening and diagnoses processes. The mean BMI of the U.S. adult population also increased significantly over the study period and the prevalence of obesity increased from 21.2 percent in 1988 to 1994 to 32 percent among persons without diagnosed diabetes in 2005 to 2010. The authors suggest that the increase in diabetes rates can be explained by the increase in obesity, and the authors of an accompanying editorial also attribute the increase in diabetes prevalence to dietary changes and lack of physical activity.
Article: Trends in Prevalence and Control of Diabetes in the United States, 1988-1994 and 1999-2010, E. Selvin, C.M. Parrinello, D.B. Sacks, and J. Coresh, Annals of Internal Medicine, DOI: 10.7326/M13-2411, published online 14 April 2014.