BOSTON – Examination of weight-loss patterns in over 177,000 people has revealed that, regardless of the initial 6-month weight loss, after 2 years the majority of patients become “cyclers,” with periods of weight gain and loss rather than maintenance of the initial weight loss.
“One-third of American adults are obese. In 2010, the cost of obesity and obesity-related comorbidities in the United States was estimated to be $315.8 billion. Achieving and maintaining weight loss has proven to be difficult,” said Joanna Huang, PharmD, senior manager of health economics and outcomes research at Novo Nordisk, Plainsboro, N.J., and lead investigator of the study presented at the annual meeting of the Endocrine Society.
The study examined the electronic records of about 178,000 obese patients whose weight loss had been by deliberate intent and not due to illness. The subjects were allocated into four groups based on the extent of weight loss in terms of body mass index (BMI) over 6 months: Those who remained stable and lost less than 5% (n = 151,902), those who lost 5%-10% (modest loss; n = 16,637), those who lost 10%-15% (moderate loss; n = 4,035), and those who lost in excess of 15% (high loss; n = 5,945).
The subjects who were at least 18 years of age at baseline (mean age 54-58 years), had at least one BMI measurement that was indicative of obesity (greater than or equal to 30 kg/m2), with at least four BMI determinations done over at least 5 years. Subjects were mostly white (about 66% in all four groups) and mostly from the southern United States.
Regardless of the amount that the participants lost in the first 6 months, regain of 50% of more of body weight was common in the modest weight-loss group (40%) and moderate weight-loss group (36%), while only 19% of those in the high weight-loss group cycled back up in weight, reported study presenter Maral DerSarkissian, PhD, of the Analysis Group in Boston.
More than 73% and about 70% of those in the moderate and modest weight-loss group, respectively, experienced weight cycling within 2 years. In the stable and high weight-loss groups, the situation was somewhat more optimistic, with about 60% of participants cycling in weight within 2 years. Total regain of lost weight occurred in about 23%, 16%, and 7% of the modest, moderate, and high weight-loss group, respectively.
“Weight loss maintenance, even in the moderate and high weight-loss groups, is very difficult to achieve,” said Dr. Huang.
Interventions that seek to maintain the weight conventionally are directed at dietary changes. But, according to Dr. DerSarkissian, “these modifications alone might not be enough to achieve and maintain weight loss.”
Pharmacotherapy is another weight-loss option. The data indicated that only 2% of the participants were receiving weight-loss pharmacotherapy. Whether this figure is accurate is an open question, according to Dr. Huang, since a lot of the data were compiled from physicians’ notes. Since clinicians may not record weight-loss advice offered to their patients, the data base may well not reflect lifestyle interventions, including pharmacotherapy.
In addition, since the data captured only primary outpatient care, whether or not a patient ever had bariatric surgery was unknown. Other unrecorded factors that can influence weight over time included comorbidities, use of medications, diet changes, and changes in physical activity.
The data points to a multifactor approach to weight loss that includes counseling, positive reinforcement, dietary advice, pharmacotherapy where appropriate, and, in some cases, bariatric surgery.
“Successful and sustained clinically meaningful weight loss requires chronic and effective weight management strategies,” said Dr. Huang.
Dr. Huang is an employee of Novo Nordisk and Dr. DerSarkissian is a researcher for Novo Nordisk.