Diet, Medication Can Help in Weight Loss for Obese Patients; Adherence Needed
A special low-calorie diet and appetite suppressing medications — either alone or together — led to substantial weight loss for obese people with Prader-Willi syndrome (PWS), a small study showed.
However, many patients struggled to adhere to the treatment regimens and eventually regained the weight, the researchers reported.
A very low energy diet or “VLED and pharmacotherapy can achieve substantial weight loss in some individuals with PWS though non-adherence results in substantial weight regain,” the researchers wrote.
The study, “Intensive management of obesity in people with Prader-Willi syndrome,” was published in the journal Endocrine.
Excessive appetite, or hyperphagia, is one of the most common symptoms of PWS, and leads to overeating and obesity. Cardiorespiratory complications resulting from obesity are a leading cause of death among people with this rare genetic disease.
However, little data exist on whether weight loss interventions are a successful approach to managing obesity in PWS.
To learn more, a research team in Australia examined medical records from PWS patients who attended an obesity management clinic and received some form of intensive weight loss intervention.
At the clinic, obese patients had a choice of weight-loss interventions: a special low-calorie diet, appetite-reducing medications, or a combination of the two.
A full VLED program featuring the very low energy diet consisted of three meal replacement products along with two cups of non-starch vegetables — 40% protein, 40% carbohydrate, and 20% fat.
A partial VLED program, meanwhile, consisted of two meal replacement products, and also provided one meal with lean protein and two cups of non-starch vegetables.
Weight loss medications included phentermine and topiramate, liraglutide, or naltrexone-bupropion.
In total, 18 people with PWS were treated at the clinic during the study period, and of them, 15 underwent an intensive weight loss intervention. Three did the diet alone, seven received medication alone, and five did both.
At the study’s start, or baseline, the patients’ median age was 20, and their median body weight was 90 kg (about 200 pounds).
Among those who received the special diet, the median peak weight loss from the study’s start was 14 kg (about 30 pounds) over a median of 60 weeks, or a little over a year. A longer time on the diet generally correlated with greater weight loss for these obese patients.
With regard to medication, the seven people on phentermine and topiramate lost the most weight. Their median peak weight loss was 17 kg (about 37 pounds) over 58 weeks, or just longer than a year.
For the seven people who received liraglutide, the median peak weight loss was 9 kg (about 20 pounds) over 96 weeks, or almost two years. A median peak loss of 2 kg (about 4 pounds) over 18 weeks was seen across the four people who took naltrexone-bupropion.
Medication was discontinued in five people who had side effects from treatment — three due to phentermine, who experienced insomnia and psychosis, and two on topiramate, who had symptoms that included rash, depression, and memory impairment. The researchers noted that these medications also are associated with a high rate of adverse effects in the general population.
Among all 15 patients who received any intervention, 14 achieved at least a 5% loss of body weight at their lowest point, and 13 achieved at least a 10% loss.
However, discontinuation of medication or non-adherence to the diet led to eventual weight regain for a majority of patients. The overall median final weight was not significantly different from baseline weights, the end results showed.
Importantly, five individuals maintained at least a 10% weight loss at their last follow-up visit. These individuals tended to have lower baseline weights than those who did not maintain weight loss.
Eight patients had more than five years of follow-up data. Among them, one individual continued the dietary treatment, one continued liraglutide, and one remained on naltrexone-bupropion. Three people began using semaglutide, another appetite-suppressing therapy, and two people were using neither the diet nor medication.
Overall, the findings show that obese PWS patients can achieve clinically meaningful weight loss with a very low-energy diet and/or appetite suppressing medications, but adherence to the regime is critical to maintaining a more healthy weight.
“Further long-term controlled trials evaluating VLEDs and obesity pharmacotherapy, including combination pharmacotherapy, in the PWS population are required,” the researchers wrote, adding, “Newer pharmacological agents including [a specific dose of the medication semaglutide], which has been demonstrated to have clinically significant weight loss in a randomised controlled trial of individuals with overweight or obesity, could be evaluated in individuals with PWS.”