Patients who lose 10% of their body weight within 6 months of diagnosis of pre-diabetes may reduce their risk of developing type 2 diabetes by 85% over the next 3 years, according to findings from a large nationwide study published online ahead of print in the Journal of General Internal Medicine.
“Even modest weight loss at 6 months (eg, 3%-5%) decreases diabetes risk significantly,” said lead author Nisa Maruthur, MD, Assistant Professor of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD. The findings can be used to guide escalation of preventive efforts, she said. “Depending on fasting glucose and weight loss at 6 months with lifestyle change, metformin could be considered for some patients—for example, patients who do not have success losing weight and whose fasting glucose remains elevated,” Dr. Maruthur added.
“Since health care providers see their patients at least annually, not every 3 years, this information is significant since this data reveals the benefits of early intervention,” commented Amy Hess-Fischl, CDE, RD, a diabetes educator and program coordinator for the Teen and Adolescent Diabetes Transition Program at the University of Chicago’s Kovler Diabetes Center.
In addition to showing that greater weight loss at 6 months predicts decreased 3 year diabetes risk, the findings also suggest that “achievement of fasting blood glucose <100 mg/dL at 6 months (ie, a normal glucose level) is beneficial regardless of weight loss,” Ms. Hess-Fischl said. “So, this data reveals that the health care providers can help the patient have a bigger impact on long-term reduction if they are more aggressive with reducing blood glucose and weight in the first 6 months,” she added.
The researchers analyzed data from 3,041 overweight adults with hyperglycemia enrolled in the Diabetes Prevention Program. The patients were randomized to intense lifestyle intervention, metformin (850 mg twice daily) plus standard lifestyle recommendation, or placebo plus standard lifestyle recommendation and were followed for an average of 2.8 years.
Patients in the lifestyle intervention group had an exercise goal of ≥150 minutes a week and received counseling, including an individualized 16-lesson curriculum covering diet, exercise, and behavior modification. The counseling was given on an individual basis for the first year and in a group setting thereafter.
The incidence of diabetes was 4.8, 7.8, and 11.0 cases per 100 person-years in the lifestyle intervention, metformin, and placebo groups, respectively. The intervention was linked to a 58% reduction in incidence of diabetes compared with placebo and metformin was linked to a 31% reduction, with the intervention being significantly more effective than metformin (P<0.001).
In the intervention group, 50% achieved the goal of a ≥7% weight loss at 1 year and 37% did so at the last followup visit (average, 2.8 years). The average weight loss was significantly greater in the intervention group (5.6 kg) than in the metformin (2.1 kg) or placebo groups (0.1 kg; P<0.001).
Given that the analysis involved data from the Diabetes Prevention Program, “this is gold standard information,” Ms. Hess commented. “The only weakness is that it is retrospective data,” she said.
“Physicians can look at our study to see what the impact of weight loss and fasting glucose at 6 months might be on their patients’ longer-term diabetes risk. Our study also gives physicians numbers that they can use in conversations with their patients regarding their diabetes risk,” Dr. Maruthur said.
Maruthur NM, Ma Y, Delahanty LM, et al. Early response to preventive strategies in the Diabetes Prevention Program. J Gen Intern Med. 2013 [Epub ahead of print]