COVID-19 Outcomes in CF Patients Similar to General Public, Study Suggests

People with cystic fibrosis (CF) infected with the new coronavirus appear to have better outcomes than initially anticipated, with their COVID-19 disease following a course similar to that of the general population, an international study suggests.

This research also points to a lower incidence of coronavirus infections in this patient group compared to the public-at-large, possibly due to a lifelong adherence to social distancing and other measures that mitigate an infection risk.

The study, “A Multinational Report to Characterise SARS-CoV-2 Infection in People with Cystic Fibrosis,” was published in the Journal of Cystic Fibrosis.

CF patients are believed to be highly vulnerable to SARS-CoV-2 infections, not only because their disease chronically affects the lungs, but also because of comorbidities. About one-third of patients develop other conditions, such as diabetes, that appear to increase the risk of severe coronavirus infections.

To avoid contracting the virus, these people are being advised to stay at home at all times, avoiding contact with anyone outside their household. But the real impact of coronavirus infections in this patient group is largely unknown.

The Cystic Fibrosis Registry Global Harmonization Group aimed to gather as much information about these patients as possible, to better understand the severity of coronavirus infections and outcomes in those with CF.

The collaborative effort was joined by the Cystic Fibrosis Foundation (CFF) in the U.S., which is gathering data through its Cystic Fibrosis Foundation Patient Registry, and many other national CF Registries worldwide. As of April 13, eight countries had submitted data, including the U.S., U.K., Australia, Canada, France, Ireland, the Netherlands, and New Zealand.

“The international cystic fibrosis community has moved with exceptional speed to establish a mechanism for rapid learning about COVID-19 and CF,” Bruce Marshall, MD, chief medical officer of the CFF and a study author, said in a press release. “It is critical to understand the specific risks this novel virus poses to people with CF.”

The registry included 40 cases of CF patients who had tested positive for SARS-CoV-2 between Feb. 1 and April 13. Patients whose imaging scans were suggestive of coronavirus infections but without a positive test were not included in the analysis.

Overall, the study included 17 men and 23 women, with a median age of 33 (range, 15 to 57). About one-third (38%) had CF-related diabetes, and 70% had a chronic bacterial pulmonary infection, mostly Pseudomonas aeruginosa (71% of this group). Eleven had undergone a lung transplant, one a kidney transplant, and one patient was pregnant.

At the time of testing, 31 patients had symptoms of COVID-19, including 24 with fever, 10 with shortness of breath, and 15 with an altered cough.

More than half, 25, were started on new antibiotics as a treatment: 10 on oral antibiotics and 17 on intravenous antibiotics (including two on both). Thirteen patients needed oxygen therapy, one needed invasive ventilatory support, and four were admitted to an intensive care unit.

Those who underwent transplants were more likely to require such attention than those without a transplant. The need for intensive care and oxygen therapy among patients taking CFTR modulators was similar to that of the overall study population.

At the time of the report, 28 or 70% of these patients had recovered, including the pregnant woman who delivered a healthy baby. No deaths were reported to any of participating registries by the study’s end.

These early findings “suggest that the course of disease in CF may not be as severe as expected from initial data from patients with other underlying lung diseases,” the researchers wrote.

“To date, incidence of SARS-CoV-2 amongst the CF population (0.07%) appears to be lower than the average derived on 13 April from the general populations of participating countries (0.15%),” they added.

While it is early to draw conclusions, the team believes this lower incidence among CF patients may be because patients adopted protective measures earlier, and ones more effective at reducing infection risk than the general public. It may also be because CF patients are younger on average, and due to lags in reporting, the team noted.

“We are encouraged that these early data do not paint a worst-case scenario for people with CF, but continued vigilance is needed as we continue to learn about SARS-CoV-2 alongside the broader scientific community,” Marshall said.

“People with CF should continue to strictly follow public health advice to protect themselves from infection,” the team wrote.

The CFF announced, in a follow to this study, that 19 more cases of coronavirus infections in CF patients in the U.S. were reported as of April 29, bringing the country’s total known number to 25. One has died of COVID-19 complications.