Most people cycle and regain weight, and those who lose most are most likely to keep it off

"About two-thirds of American adults are overweight or obese, and the economic and health burdens of the obesity epidemic are substantial. Achieving and maintaining weight loss has proven to be difficult," said study lead author Joanna Huang, PharmD, senior manager of health economics and outcomes research at Novo Nordisk Inc. in Plainsboro, New Jersey. "Many patients regain weight after their initial loss; and even after a period of weight loss, most people become 'cyclers' who regain weight or experience inconsistent losses and gains."

To analyze trends in weight change, Huang and her colleagues reviewed the electronic medical records of 177,743 obese patients who had no medical conditions associated with unintentional weight loss and who had been having annual body mass index (BMI) measurements for five years or longer.

Based on the percentage of BMI lost within six months of the first BMI measurement, the patients were organized into one of four weight-loss groups: stable (less than 5 percent of first BMI lost); modest loss (5 percent to less than 10 percent); moderate loss (10 percent to less than 15 percent); and high loss (15 percent or more).

Patients who lost more weight early on were more likely to continue to lose weight over time. Among patients with modest weight loss, 23.1 percent maintained their weight and 2.0 percent continued to lose weight over the two-year monitoring period; in those with moderate weight loss, 14.1 percent maintained their weight loss and 4.1 percent continued to lose weight; and in those with high weight loss, 19.4 percent maintained their weight and 11.1 percent continued to lose weight.

But over the two years, fewer patients maintained their weight. In the modest, moderate, and high weight-loss groups, 40.0 percent, 35.9 percent, and 18.6 percent of patients, respectively, regained over half of their lost weight during the maintenance period.

And most patients in each group experienced weight cycling or weight regain. The high weight-loss group had the lowest proportion of cyclers with 58.3 percent, while 71.5 percent of the modest weight loss group and 74.1 percent of the moderate weight loss group were cyclers.

"These important challenges require further attention. We hope these results highlight the importance of chronic, consistent and conscientious weight loss and management," Huang said. "Identifying patterns of weight change is critical for tailoring weight management strategies to the needs of targeted patient groups."