COVID Long-Haulers May Experience Abnormal Breathing and Chronic Fatigue Syndrome

The findings are consistent with long-distance symptoms following the 2005 SARS epidemic.

Many long-haul COVID-19 patients have chronic fatigue syndrome and other respiratory problems months after their initial COVID-19 diagnosis, according to a study in JACC: Heart Failure, which is the first of its kind to identify a link between long-haul COVID-19 and chronic fatigue syndrome.

Chronic fatigue syndrome is a medical condition that can often occur after a viral infection and cause fever, pain, and prolonged fatigue and depression. Many COVID-19 patients, some who have never been hospitalized, have reported persistent symptoms after recovering from their initial COVID-19 diagnosis. These patients have PASC (Post-Acute Sequelae or SARS-CoV-2 infection), but are more often referred to as ‘lung haulers’. Severe fatigue, cognitive difficulties, unrefreshing sleep, and muscle aches (muscle pain) were all considered major symptoms for PASC patients, which is similar to what researchers saw after the 2005 SARS-CoV-1 epidemic, in which 27% of the patients met the criteria. for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) at four years.

In this study, researchers looked at 41 patients (23 women, 18 men) with an age range of 23 to 69 years. Patients were referred to the prospective study by pulmonologists or cardiologists and all had normal lung function tests, chest radiographs, CT scans of the chest, and echocardiograms. Patients had been previously diagnosed with acute COVID-19 infection for a range of three to 15 months before undergoing the cardiopulmonary exercise test (CPET) and continued to experience unexplained shortness of breath.

“Recovery from acute COVID infection may be associated with residual organ damage,” said Donna M. Mancini, MD, a professor of cardiology at the Icahn School of Medicine at Mount Sinai and lead author of the study. “Many of these patients reported shortness of breath, and the cardiopulmonary exercise test is often used to determine the underlying cause. The CPET results show several abnormalities, including decreased exercise capacity, excessive respiratory response and abnormal breathing patterns that would affect their normal daily activities.”

Prior to exercise, patients underwent interviews to assess for ME/CFS. They were asked to estimate how much fatigue in the past six months had reduced their activity at work, in their personal lives, and/or at school; and how often they had experienced sore throat, tender lymph nodes, headache, muscle pain, joint stiffness, unrefreshing sleep, difficulty concentrating, or worsening of symptoms after mild exercise. ME/CFS was considered present if at least one of the first criteria was rated as substantially affected and at least four symptoms in the second criteria were rated as moderate or greater. Nearly half (46%) of patients met criteria for ME/CFS.

Patients connected to an electrocardiogram, pulse oximeter and blood pressure cuff sat on a stationary bicycle and used a disposable mouthpiece to measure exhaled gases and other respiratory parameters. After a short rest period, the patients started with exercises increasing by 25 watts every three minutes. Peak oxygen consumption (VO2), CO2 production and respiration rate and volume were measured.

Nearly all patients (88%) had abnormal breathing patterns called dysfunctional breathing. Dysfunctional breathing is most often observed in asthmatics and is defined as rapid, shallow breathing. Patients also had low CO2 levels at rest and during exercise, indicating chronic hyperventilation. In addition, most patients (58%) showed signs of decreased circulation to maximum exercise performance due to either cardiac dysfunction and/or abnormal pulmonary or peripheral perfusion.

“These findings suggest that in a subset of long transporters, hyperventilation and/or dysfunctional breathing may underlie their symptoms. This is important because these abnormalities can be addressed with breathing exercises or ‘retraining,’” says Mancini.

There are several limitations to this study. This is a small, single-center observational study. There may have been a selection bias when the researchers studied patients with predominantly unexplained dyspnea. Correlation of the findings with lung and cardiac imaging should also be performed.

Reference: “Use of cardiopulmonary stress testing for patients with unexplained dyspnea after coronavirus” Nov 29, 2021, JACC heart failure.
DOI: 10.116/j.jchf.2021.10.002