A new study by University Hospital Bern looked at the role of fatigue in patients with Long COVID, also referred to scientifically as post-COVID-19 syndrome. The study’s key findings are as follows:
- Fatigue is the predominant symptom of post-COVID-19 syndrome. About seven months after acute COVID-19 infection, more than 90% of the patients studied still suffered from it.
- Depression (52.4%) and daytime sleepiness (32.4%) were frequently observed as possible exacerbating factors for fatigue in this population not previously affected by fatigue.
- Patients with fatigue were found to have elevated ferritin levels compared to the rest of the population. Ferritin is a protein that increases during the acute phase of infection. The elevated levels in patients with Long COVID support the hypothesis that fatigue in Long COVID may be caused by underlying immunological disorders.
Fatigue occurred in over 90% of Long COVID patients studied.
Investigation and questionnaires
The study is based on 42 patients treated in the neuroimmunology Long COVID clinic at Bern Inselspital between November 2020 and May 2021. The investigation included an account of the course of the acute infection and current symptoms, a physical examination and the completion of questionnaires on fatigue, mood and daytime sleepiness. Added to this was a detailed laboratory investigation that was performed to exclude secondary causes of fatigue.
Gender and age not relevant
There was no gender difference or difference in the severity of the COVID-19 infection between patients with and without fatigue. In addition, the time between acute infection and fatigue assessment, age and body mass index (BMI) did not correlate with the severity of fatigue. In other words, fatigue can occur in virtually all people affected by Long COVID.
“Depressive symptoms and sleep disturbance are common in Long COVID patients, and should be actively diagnosed and treated.”
Depression another common symptom
Sleep disturbance and depressed mood were two other common symptoms that occurred in 47.6% and 52.4% of the cohort respectively. Lara Diem, Senior Physician in Neurology at Inselspital Bern and the study’s author, explains: “It’s important to actively diagnose and treat these symptoms in Long COVID patients.”
The question of how depression affects fatigue is difficult to answer, because both often occur simultaneously. The COVID-19 pandemic has also led to an increased prevalence of severe depression and anxiety disorders as a result of infection rates and lockdown measures. In Long COVID, however, fatigue is also very common independent of depressive symptoms, which suggests that depression is not likely to be the primary cause of fatigue, but rather a secondary consequence of it.
Further studies needed
In conclusion, fatigue appears to be the main symptom of post-COVID-19 syndrome in patients referred to neurological hospital care. Despite the small sample size, the results of the study shed light on the postinfectious origin and possible immunological mechanisms of fatigue in patients with Long COVID.
Dr. Diem adds: “Further studies describing post-COVID-19 syndrome and offering treatment recommendations are needed to help health systems meet the challenge of treating patients with Long COVID.”
