Joslin Reports Benefits of Weight-Loss Intervention Can Last 5 Years

January 5, 2017

The intervention involves limiting carbohydrates to 40% of calories and having participants maintain muscle mass, so energy levels remain high.

An intensive lifestyle intervention program for obese patients with diabetes, called Why WAIT, produced benefits for participants a full 5 years after they started, according to results announced this week by Joslin Diabetes Center.

The latest findings, published in BMJ Open Diabetes Research & Care, showed that participants had an average weight loss of 9.7% (24 pounds) after the initial 12-week intervention, and that they maintained a weight loss of 6.4% (16 pounds) after 5 years. All participants in this study were obese, starting with an average body mass index (BMI) of 38 kg/m2—well above the CDC obesity standard of 30 kg/m2.

Why WAIT, which stands for Weight Achievement and Intensive Management, combines nutritional changes, exercise, medication, education, and monitoring. Unlike some exercise programs, this intervention calls for participants to maintain muscle mass through strength training so that weight loss is from fat.

With this approach, “People will retain high energy expenditure for the long term,” said Osama Hamdy, MD, PhD, FACE, medical director of Joslin’s Obesity Clinical Program and an assistant professor at Harvard Medical School.

“To the best of our knowledge, this is the longest follow-up in the real world of clinical practice to show encouraging results that weight loss can be achieved and maintained,” Hamdy, the lead author, said in a statement from Joslin.

Hamdy’s work on Why WAIT has been instrumental in showing why achieving a significant amount of weight loss, correctly, can have long-term benefits for those with diabetes. The Joslin intervention has found that long-term results for those who achieved 7% weight loss during the initial intervention differed sharply from those who achieved less.

This concept, that programs should seek “transformational” weight loss to prevent cardiovascular problems over the long haul, is behind efforts like Medicare’s decision to fund the National Diabetes Prevention Program, starting in January 2018. CMS’ initial proposal called for at least some reimbursement to be tied to participants achieving at least 5% weight loss. The population targeted here has prediabetes, which means they are at risk of developing type 2 disease.

In the new Why WAIT results, those who achieved an initial weight loss of 7% maintained an average loss of 9.3% after 5 years, while the group that did not make the 7% mark only maintained a weight loss of 3.5% after 5 years. The divide played out in different glycated hemoglobin (A1C) levels between the 2 groups (all had type 2 diabetes when the study began):

  • The group that achieved 7% saw A1C levels drop from 7.4% to 6.4% at 12 weeks and then slowly return to 7.3% over the 5-year period. This group maintained improvements in both low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol.
  • Those who did not achieve 7% weight loss saw their average A1C fall from 7.5% to 6.7%, but then rise to 8.0% at the 5-year mark. Patients in this group had more prescriptions for insulin and oral diabetes medications during the follow-up period; curiously, this group had better LDL and HDL levels.

As Hamdy told Evidence-Based Diabetes ManagementTM in 2015, diabetes is a progressive disease, so reversing or slowing the progression of increases in A1C is a “revolution” in disease management.

The Why WAIT study also showed the virtues of keeping carbohydrates below 40% of total calories, in contrast with what was official US nutrition policy in prior decades.

Reference

Hamdy O, Mottalib A, Morsi A, et al. Long-term effect of intensive lifestyle intervention on cardiovascular risk factors in patients with diabetes in real-world practice: a 5-year longitudinal study. BMJ Open Diab Res Care. 2017;5:e000259. doi:10.1136/bmjdrc-2016-000259.