Adults with XLH Have Greater Risk of Obesity, French Study Indicates
Adults with X-linked hypophosphatemia (XLH), especially those younger than 45, have an increased likelihood of excess weight and obesity compared to the general population in France, a study found. Researchers have recommended lifestyle changes and physical activity for these patients.
The study, “SUN-336 Obesity and Impaired Glucose Metabolism in Adult Patients with X-Linked Hypophosphatemia,” was published in the Journal of the Endocrine Society. The results were intended to be presented at ENDO 2020, the annual conference hosted by the Endocrine Society that was cancelled due to the COVID-19 pandemic,
XLH is characterized by lower levels of phosphate in the blood due to increased activity of a protein called fibroblast growth factor 23, or FGF23, that is involved in phosphate regulation.
Recent studies have indicated that FGF23 dysregulation can lead to both weight gain and metabolic issues. Researchers at the University of Paris-Saclay and their collaborators investigated whether these issues occurred in people with XLH.
The team recruited 107 patients (median age 35.5), whose prevalence of obesity and diabetes were compared to the general French population. In turn, prevalence of glucose intolerance in patients was compared to matched controls.
According to their body mass index (BMI), a ratio of weight to height, researchers determined that 38 patients (35.5%) were overweight and 222 were obese (20.5%). Compared to the general population, XLH patients had a 20% higher prevalence of overweight and obesity, particularly in patients younger than 45.
The study also investigated metabolic issues in XLH patients, including diabetes, glucose intolerance, and cells not responding properly to insulin, which is a condition called insulin resistance.
Results also showed that three patients (2.8%) were being treated for type 2 diabetes, a similar percentage to that in the French population (5%).
Glucose intolerance, as measured by the 75-gram oral glucose tolerance test that assesses blood glucose levels before and after a person drinks a liquid with 75 grams of glucose, also was equally present in XLH patients (13%) and matched controls (12%).
Also, 14 adults with XLH (15.6% of those with available data) showed decreased insulin sensitivity, which was measured with the HOMA-IR score. The team said that insulin sensitivity in XLH needs to be further tested and compared to controls.
Overall, the researchers concluded that weight gain was prevalent in patients with XLH, but there was not an increased risk of metabolic issues.
“Adult XLH patients are prone to develop overweight and obesity, particularly adolescents and young adults,” the researchers wrote. “This excess of weight does not seem to result in increased prevalence of metabolic disorders.”
They recommended incorporating lifestyle changes, including physical activity, to prevent obesity in XLH.
