Morbid obesity among people with diabetes is increasing at a very alarming rate, says kidney expert

Loyola University Health SystemNov 23 2009

1 in 5 are approximately 100 pounds overweight

A Loyola University Health System study has found that one out of five Type 2 diabetics is morbidly obese -- approximately 100 pounds or more overweight.

Researchers reported that 62.4 percent of U.S. adults with Type 2 diabetes are obese, and 20.7 percent are morbidly obese. Among African American adults with Type 2 diabetes, 1 in 3 is morbidly obese.

"The rate of morbid obesity among people with diabetes is increasing at a very alarming rate, and this has substantial public health implications," said Dr. Holly Kramer, a kidney specialist and lead author of the study published online in the Journal of Diabetes and its Complications.

Kramer and colleagues examined data from the National Health and Nutrition Examination Surveys completed during the years 1976 to 2006. The surveys, known as NHANES, included interviews and physical examinations of representative samples of the U.S. population.

Between the survey periods 1976-1980 and 2005-2006, there was a 141 percent increase in the rate of morbid obesity among adults with Type 2 diabetes, the most common form of diabetes.

Morbid obesity is defined as having a body mass index (BMI) greater than 40. BMI is a measure of body fat based on height and weight. For example, a 5-foot-2-inch adult with a 40 BMI weighs 218 pounds (82 pounds overweight), while a 6-foot-2-inch adult with a 40 BMI weighs 311 pounds (117 pounds overweight).

The greatest growth in obesity has been among diabetics who are morbidly obese. Thus, focusing solely on overall obesity rates "hinders the complete comprehension of this massive public health problem," Kramer and colleagues wrote.

Diabetics already are at higher risk for cardiovascular disease, and obesity further increases this risk, especially among women. Obesity also increases other diabetes complications, including end-stage kidney disease. Other obesity complications include sleep-disordered breathing, arthritis and fatty liver disease.

Approximately two-thirds of adults with Type 2 diabetes are obese and about one-third of adults without diabetes are obese. Obesity is defined as having a BMI greater than 30 -- approximately 30 pounds overweight.

Between 1976 and 2006, the average BMI of Type 2 diabetics increased 17 percent, to 34.2. The average BMI of adults without Type 2 diabetes increased 11.5 percent to 28.1. (A BMI of 25 or more is considered overweight.)

The average age of adults with Type 2 diabetes increased from 56.7 years in 1976-1980 to 59.9 years in 2005-2006. The percentage of Type 2 diabetics who were men increased from 42.9 percent to 46.3 percent.

Among the reasons for the increase in obesity among diabetics and the overall population are inexpensive food, larger portion sizes and consumption of sugary soda, Kramer said. Stomach-stapling gastric bypass surgery can be a last resort for morbidly obese diabetics who have been unable to control their weight through diet and other lifestyle changes. In many patients, weight-loss surgery can eliminate the need for diabetes-related medications.

Kramer is an associate professor in the Department of Medicine, Division of Nephrology at Loyola University Chicago Stritch School of Medicine. Her co-authors, all in the Department of Preventive Medicine and Epidemiology, are Guichan Cao, Lara Dugas, Amy Luke, Richard Cooper and Ramon Durazo-Arvizu.