BOSTON – Significant weight reduction in obese patients with diabetes can be maintained for 5 years in a “real world” clinical practice setting, but such long-term maintenance is most likely in those who maintain at least 7% weight loss at 1 year, according to findings from the Weight Achievement and Intensive Treatment (Why WAIT) program.
Sustained weight loss in 129 program participants who were included in the longitudinal study was associated with lower hemoglobin A1c for 5 years, and with lower blood pressure for the first 18 months; HbA1c and triglycerides, however, were the first risk factors to deteriorate with weight regain, Dr. Osama Hamdy reported at the annual scientific sessions of the American Diabetes Association.
The study subjects had completed the Why WAIT program – a 12-week intensive lifestyle intervention model designed for clinical practice – and were grouped according to their percentage weight loss: Group A included 61 patients who failed to maintain at least 7% weight loss, and group B included 68 patients who maintained at least 7% weight loss.
Overall, the total cohort lost an average of 23.8 pounds (–9.7%) and maintained an average of 16.2 pounds lost (–6.4%). Group A maintained an average of 8.4 pounds lost (–3.5%) and group B maintained an average of 23.1 pounds lost (–9.0%) at 5 years.
HbA1c decreased from 7.5% to 6.7% at 12 weeks in the group A patients, but increased to 7.7% at 1 year, and to 8.0% at 5 years. HbA1c decreased from 7.4% to 6.4% at 12 weeks in the group B patients, but increased to 6.8% at 1 year, and to 7.3% at 5 years, said Dr. Hamdy, medical director of the obesity clinical program, and director of the inpatient program at Joslin Diabetes Center, Harvard Medical School, Boston.
Despite the weight regain, group A subjects maintained significant improvement in both low- and high-density lipoprotein cholesterol levels. They had no change in blood pressure, but had worsening of serum triglycerides, noted Dr. Hamdy, whose abstract received the 2015 ADA Michaela Modan Memorial Award for top abstracts in the areas of human studies on the epidemiology, complications, and prevention of diabetes.
Group B subjects experienced similar improvement in lipid profile, but had lower blood pressure for the first 18 months.
Weight loss through intensive lifestyle interventions are typically followed by either weight regain or sustained weight loss after the first year, but the impact of sustained weight loss vs. weight regain on cardiovascular risk factors was unknown, Dr. Hamdy said.
Thus, he and his colleagues evaluated the impact in Why WAIT participants. Why WAIT is a multidisciplinary approach to weight loss that involves structured dietary interventions and modified macronutrient composition, gradual balanced and individualized physical activity (including flexibility, aerobic, and strength training), adjustment of medications that affect body weight (including diabetes medications and antidepressants), cognitive behavioral modification, and group diabetes education.
“Our study demonstrated that sustained weight loss is associated with improved diabetes control for 5 years, and improved blood pressure for the first 18 months,” he said, noting that the ability to maintain at least 7% weight loss at 1 year predicts long-term wight loss.
The study “provides further understanding that regaining the weight does eliminate some of the benefits associated with the initial weight loss,” he added.
The findings change the misconception that people who lose weight with nonsurgical interventions will fail to maintain their weight loss beyond 6 months, he said.
“Our patients maintained 6.4% weight loss after 5 years, and approximately 53% of them achieved an average of 9% weight loss.”
The Why WAIT study is supported by Joslin Diabetes Center. Dr Hamdy reported that he has received research support and is an advisory panel member and author for Metagenics, that he is a consultant and author for Abbott Nutrition and Merck & Co., and that he has received research support and is an author for Neurometrix.
* This article was updated on 6/8/2015