Study: PWS Doesn’t Increase Risk of Severe COVID-19
Children and adults with Prader-Willi syndrome (PWS) are not at higher risk of developing a severe COVID-19 infection, according to results from a survey involving more than 500 patients in France.
These findings were particularly surprising in terms of the adult population, which typically has several known risk factors for severe COVID-19, such as obesity and diabetes.
The relatively young age of the infected adult patients (mean of 34 years) may help explain the results, but further studies are needed to clarify whether other factors inherited to the PWS population, either biologically or pharmacologically, have a protective effect, the researchers noted.
The study, “Paradoxical low severity of COVID-19 in Prader-Willi syndrome: data from a French survey on 647 patients,” was published in the Orphanet Journal of Rare Diseases.
In the general population, it is well established that COVID-19 severity and mortality increase with older age and the presence of simultaneous health conditions, such as cardiovascular disease, lung disease, obesity, diabetes, chronic kidney disease, cancer, and smoking.
PWS, the most common genetic cause of obesity, is associated with insatiable hunger, developmental delays and learning difficulties, temper outbursts, compulsion, and difficulties adapting to changes.
As such, adults with PWS typically have several risk factors of severe COVID-19 infection, including obesity and diabetes. In addition, adult patients also may be at higher risk of infection “because many of them live in a community structure and social distancing can be difficult in adults with intellectual and developmental disability,” the researchers wrote.
However, no study to date has evaluated the course of COVID-19 infection in PWS patients.
To address this knowledge gap, a team of researchers in France conducted a COVID-19-related medical survey among patients routinely followed at three sites of the French reference center of PWS.
The team contacted the families of 342 adults and 305 children with genetically confirmed PWS by telephone and/or e-mail from November 2020 to January 2021 to assess whether patients had been infected with COVID-19 from March 2020 to January this year.
Responses were obtained for 288 adults (84%) and 239 children (78%).
When a COVID-19 case was reported by the consulted families, a detailed medical questionnaire related to the affected patient was filled by a clinician from the center of reference and medical records were consulted.
Results showed that 38 adults (13.2%), with a mean age of 34.1 years, and 13 children (5.4%), with a mean age of 9.6 years, had COVID-19. The infection rate in adults was within that reported for the French general population. No equivalent data exist from children, the scientists said.
Half of these adult patients were living in a residential group home at the time of infection, while all infected children were living at home. Ten adults were hospitalized when infection occurred; nine were due to a small outbreak in a PWS rehabilitation unit.
Most (82%) of the infected adult patients had obesity, including 55% with severe obesity, and 37% had diabetes. Only three (23%) of the infected children were obese, two (15%) had obstructive sleep apnea — a sleep disorder in which breathing stops and starts — and none had diabetes.
The majority of patients (63% of adults and 77% of children) reported symptoms, with the most common being fever (31–39%), generalized weakness (26–38%), and cough (18–23%).
Other commonly reported symptoms included shortness of breath in adults and headache in children. Loss of smell was reported in one adult and one child.
Five adults (13.2%) had pneumonia that required oxygen administration. Five of the 12 hospitalized patients had morbid obesity and most had other co-existing health conditions, including type 2 diabetes, high blood pressure, obstructive sleep apnea, respiratory failure, swelling of the legs, and a history of blood clot-related problems.
All adults and all but one child completely recovered from COVID-19 symptoms after up to 21 days. One child experienced persistent weakness several months after infection.
These findings highlighted that “despite many risk factors for severe COVID-19, such as obesity and diabetes, French adults with PWS only had mild or moderate COVID-19,” the researchers wrote.
As such, “PWS itself cannot be considered as a risk factor for severe COVID-19,” they added.
Given that older age is a main known risk factor for severe COVID-19 infection, the team hypothesized that the young age of the infected adult patients may largely explain their findings, but noted that other protective factors, yet to be elucidated, may be involved.
Vitamin D supplementation and antidepressants, which were part of the treatment regimen of many of the infected patients, also may have helped to lessen COVID-19 severity, they said.
While the study surveyed only 600 of about 1,000 families with PWS in France, patients followed at the reference center “are usually the most severe and we are not aware of severe COVID-19 in other French patients with PWS,” the team wrote.
Further studies are needed to confirm these findings and clarify the mechanisms behind the absence of a higher risk of severe COVID-19 infection in a patient population that typically has several risk factors.