ME/CFS Rates No Different After COVID-19 Infection than After Other Acute Infection-Like Illnesses

Among a cohort of approximately 4700 adults with evidence of infection-like illness who were tested for SARS-CoV-2, there was no difference in rates of subsequent myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) between those who did and did not test positive for COVID-19, according to researchers led by a team from the University of California Los Angeles.¹ 

At 12 months, 2.8% of those in the COVID-19–positive group and 4.5% in the COVID-19–negative group met the definition of ME/CFS. The weighted proportion of study participants identified with ME/CFS-like illness did not change significantly at 3 through 12 months of follow-up and remained similar in the COVID-19 positive group (range, 2.8%-3.7%) and COVID-19–negative group (range, 3.1%-4.5%), according to the study findings published in JAMA Network Open.

Nor did researchers find any significant difference between the groups in the odds of ME-CFS-like illness at any point during the study period (marginal OR range, 0.84; 95% CI, 0.42-1.67 to 1.18; 95% CI, 0.55-2.51).¹

The research was based on survey data collected 3 months to 1 year after individuals' initial illnesses.

COVID-19 Opportunity

Symptoms associated with ME/CFS are often linked to a prior acute influenza-like illness and are representative of post-acute infection syndromes; typical complaints include functional impairment linked to fatigue, exertion intolerance, and cognitive difficulties.2 Fatigue is the most common symptom reported by people with long COVID and the profile of sequelae of COVID-19 infection and other post-acute infection syndromes overlap with those of ME/CFS.¹

The elevated profile for post-acute infection syndromes during the COVID-19 pandemic created an ideal opportunity to look more closely at the incidence of ME/CFS following a specific infection, co-senior author Joann Elmore, professor of medicine, division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA, and colleagues wrote.

The team took advantage of data from the multicenter, prospective longitudinal Innovative Support for Patients with SARS-CoV-2 Infections Registry (INSPIRE) registry study, which enrolled individuals who had had an acute index illness suggestive of COVID-19 between December 11, 2020, and August 29, 2022.¹

INSPIRE participants were aged 18 to 64 years, were tested using a US FDA-approved SARS-CoV-2 test at the index illness and did not die or leave the study by 3 months.

Participants complete surveys at study baseline and quarterly for 12 months. Questions assessed physical and mental health, symptoms, access to care, and work-related outcomes. They also completed the Patient-Reported Outcomes Measurement Information System–29 (PROMIS-29) profile at baseline and at all 4 follow-up times.

The self-reported information collected only allowed investigators to determine ME/CFS-like illness and survey questions did not allow detection of chronic symptoms prior to the acute index illness.¹

Approximately one-third of the COVID-19 positive and negative groups (range, 31.0%-37.6%) reported at least 1 or more of the 5 ME/CFS symptoms queried at each of the 4 follow-up surveys, according to the results. The most frequently reported symptom was unrefreshing sleep in both groups (range, 20.2%-26.3%). Postexertional malaise was reported by 16.9% to 22.4% across groups followed by orthostatic intolerance (range, 9.0%-13.1%).

“ME/CFS is no more likely to occur in people infected with COVID-19 than people with other acute illnesses,” Elmore said in a UCLA Health news release.³ “However, a 3 to 4% prevalence of ME/CFS after an acute COVID-19 illness would impose a very high burden on society and our healthcare system given the many millions of persons infected with SARS-CoV-2.”³

The high symptom burden for INSPIRE participants meeting ME/CFS criteria was consistent through 12 months in both COVID-19 positive and negative groups, suggesting the potential for “long duration of illness and disability,” Elmore and colleagues wrote. They also noted that the prevalence of individual symptoms such as postexertional malaise and poor sleep was higher than the combined list of ME/CFS symptoms and may pose their own significant health burden.¹

“Our findings suggest that ME/CFS may follow several precipitating events (acute COVID-19 illness, other acute infections, or life disruptions due to the COVID-19 pandemic) but that regardless of reason or exact percentages, there will be millions affected who will seek care.”¹

They added that the findings also “emphasize the importance of developing clinical management strategies for patients with post–acute infection syndromes.”¹

References
1. Unger ER, Lin J-MS, Wisk LE, et al for the Innovative Support for Patients with SARS-CoV-2 Infections Registry (INSPIRE) Group. Myalgic encephalomyelitis/chronic fatigue syndrome after SARS-CoV-2 infection. JAMA Netw Open. 2024;7(7):e2423555. doi: 10.1001/jamanetworkopen.2024.23555
2. Kujawski S, Zalewski P, Newton JL. Do some long COVID patients suffer from ME/CFS? Med Res J. 2021;6(4):279-280. doi:10.5603/MRJ.a2021.0049
3. Research finds no difference in myalgic encephalomyelitis/chronic fatigue syndrome prevalence caused by COVID-19 and other acute illnesses. News release. UCLA Health. July 24, 2024. Accessed July 24, 2024. https://www.uclahealth.org/news/release/research-finds-no-difference-myalgic