Long COVID May Be Difficult to Identify in MS

WEST PALM BEACH, Fla. – People with multiple sclerosis (MS) appeared to have a low risk of developing long COVID, but lingering complaints after SARS-CoV-2 infection were difficult to untangle from MS symptoms, registry analyses showed.

In studies presented at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum, Robert Fox, MD, of the Cleveland Clinic in Ohio, said that about 1.5% of patients in the North American Research Committee on Multiple Sclerosis (NARCOMS) registry met criteria for post-acute sequelae of COVID-19 (PASC), also called long COVID.

Fox said that among MS patients with COVID-19, 15.7% had persistent symptoms 6 months after acute infection, but 17.2% of MS patients who did not have COVID or any other infection had similar symptoms for 6 months.

“Our observations illustrate how symptoms of post-acute sequelae of COVID-19 are common in people with MS sclerosis and complicate assessment of post-acute sequelae of COVID-19 in people with MS,” Fox reported.

“What our research has told us is that the current outside world criteria for long COVID can’t be applied to people with multiple sclerosis,” he said. “While there are undoubtedly some people who have long COVID and didn’t have these persistent symptoms before becoming infected with COVID-19, it is still very difficult to dissect out what is a multiple sclerosis long-term symptom and what is a COVID-19 long-term symptom.”

In a related analysis, Amber Salter, PhD, of the University of Texas Southwestern Medical Center in Dallas, Fox, and colleagues used NARCOMS data to compare the presence of new symptoms associated with SARS-CoV-2 and other infections in persons with MS. They found that after any infection, multiple new persistent symptoms were reported, but each were infrequent. The frequency of some new persistent symptoms differed between those with COVID-19 and other infections.

MS and Long COVID

The long COVID analysis used NIH scoring criteria, with a score of 12 or more indicating long COVID. In an early study from the RECOVER consortium, a score of 12 or higher was reported among 23% of participants who had a COVID infection and 3.7% of those who did not.

The NARCOMS spring 2023 survey included questions related to infections and symptoms of COVID-19, influenza, common cold, gastrointestinal (GI) tract infection, pneumonia, shingles, strep throat, skin, bone, and urinary tract infection, Fox said.

About 5,000 U.S.-based adults participated in NARCOMS and survey questions were harmonized with those used in the RECOVER study. Persistent new symptoms were defined as those symptoms that were not present before the infection, but present at the time of infection and still present at the time of survey completion.

Overall, 44.2% of eligible survey respondents reported ever having COVID-19, and 68.3% of this group (n=1,446) reported having a COVID-19 infection occurring more than 6 months ago. Nearly 77% said they had only one COVID-19 infection. The average age was 63; nearly 83% were female and 89% were white.

Symptoms After Infections

In a separate NARCOMS analysis, most MS patients reported no infections (n=1,534), followed by one non-COVID infection (n=853), COVID plus one other infection (n-728), and COVID only (n=294). Patient ages ranged from 63 to 67 and the majority were female and white.

The researchers found that in general, new persistent symptoms were uncommon after infections, but that those with only COVID-19 infection were somewhat more likely to report persistent malaise (6%), GI symptoms (3%), shortness of breath (4%), and persistent change in taste or smell (4%; P

“Participants with the highest percentage of new persistent symptoms were those reporting both COVID-19 and one non-COVID infection,” Salter noted.

“These observations suggest a complex interaction between COVID and other infections in the development of new persistent symptoms following infections,” she said.