Early Diagnosis and Treatment of PWS May Reduce Risk of Obesity, Study Suggests

Early diagnosis and treatment of Prader-Willi syndrome may delay obesity and minimize the risk for associated complications, a study suggests.

The study, “Early Diagnosis in Prader–Willi Syndrome Reduces Obesity and Associated Co-Morbidities,” was published in the journal Genes, and was led by researchers at the University of California.

Prader-Willi syndrome (PWS) is caused by the deletion of paternal genes located in a region of chromosome 15, which control metabolism, appetite, growth, intellectual function, and social behavior.

Individuals with PWS lack the ability to control their appetite and food intake. As a result, they often overeat, developing obesity and related complications that include heart disease, diabetes, and high blood pressure.

Studies have found that growth hormone replacement therapy may benefit young children with PWS, not only because it helps them to grow taller, but also because it stimulates metabolism, thereby decreasing body fat and increasing muscle mass.

“[However], the diagnosis of PWS is often delayed, leading to excessive medical costs, parental anxiety and increased time before treatment,” the investigators wrote.

The team assessed if early diagnosis of PWS followed by rapid start of treatment could reduce the risk of obesity and other medical complications in children with the disorder.

To that end, they analyzed clinical data from 352 children with PWS recruited from the National Institutes of Health Rare Diseases Clinical Research Network.

The researchers gathered several parameters, including the age of the children when they were first diagnosed with PWS, and when they started to gain weight and have difficulties controlling their appetite.

Among the group, 217 children (62%) were diagnosed before 1 year of age, 42 (12%) between ages 1 and 3, and 93 (26%) at or after age 3.

Results revealed that children who had been diagnosed earlier — before they were 1 — started to gain weight around age 10. In contrast, those who had been diagnosed later in life — after 3 years of age — began gaining weight much earlier, around age 4.

A subsequent analysis found that non-whites became heavier at an earlier age (median age of 4 years) compared to white children (age 8). No such association was found for gender or specific genetic defects leading to PWS.

Yet, age of diagnosis and race did not influence when the children started experiencing increased appetite or actively seeking food.

“In summary, early diagnosis could lead to significant improvements, with decreased costs and better medical care of affected newborns [with PWS], leading to an enhanced quality of life,” the scientists wrote. Such benefits could also be achieved in newborns with Angelman syndrome, a condition caused by maternal deletion of the same gene region associated with PWS, they said.

More research is needed to further investigate the feasibility of lowering the costs of genetic testing and its application in the newborn setting, the investigators added.