PWS Patients More Prone to Have Blood-clotting Problems Than Other Obese People, Study Shows

Although uncommon, blood-clotting problems are more likely to occur in people with Prader-Willi syndrome than in obese individuals without the disorder, researchers report.

The study, “Age Distribution, Comorbidities and Risk Factors for Thrombosis in Prader–Willi Syndrome,” was published in the journal Genes.

PWS is the most common genetic cause of obesity. Despite their rare occurrence, blood clots (thrombosis), deep venous thrombosis (when a blood clot forms in a deep vein, usually in the leg), and pulmonary embolism (when the clot moves to the lungs, blocking blood circulation in the respiratory system) have been reported in PWS patients.

These blood-clotting complications appear to affect women more frequently than men, and to be more common with older age, increased weight, and obesity.

Using two large datasets on healthcare insurance claims from 2004 to 2014, researchers at University of Kansas Medical Center investigated risk factors for blood clotting in people with PWS, and the occurrence of thrombotic episodes in those with and without this disorder.

The participants — 3,136 individuals with PWS and 3,945 controls with obesity unrelated to PWS — were identified from commercial or Medicare Advantage and Medicaid insurance groups.

In the PWS group, 2,042 patients (65.1%) were younger than 18; 1,040 (33.2%) were 18–64; and 52 (1.7%) were 65 or older.

Results showed a trend toward higher frequency of thrombosis events in PWS patients than in controls across all analyses.

After considering other conditions related to PWS (comorbidities), commercially insured patients with PWS were 2.55 times more likely to have experienced pulmonary embolism or deep venous thrombosis than controls. Medicaid coverage was associated with higher frequency of these complications in controls with obesity than in PWS patients, but this difference was not statistically significant. Importantly, these rates were consistent across all age groups.

The study found that risk factors for pulmonary embolism and deep venous thrombosis included irregular heartbeat (arrythmia), being male, obesity, high blood pressure (hypertension), diabetes, solid tumor without metastasis, chronic pulmonary disease, and HIV/AIDS.

The researchers also reported that age and gender were significant predictors of venous blood clots, regardless of insurance coverage.

“Regardless of the type of insurance coverage and services received, the occurrence of thrombosis events or blood clots increased with age in PWS and is a leading cause of morbidity and mortality that is further increased by obesity,” they wrote.

“Survival trends can improve in patients with PWS if the associated risk factors for thrombosis events such as age, gender, coagulopathy [impaired blood clotting], cardiac arrhythmias, and, especially, obesity and its related complications are targeted for proper management early and often throughout life,” the researchers added.