Recent studies published in CMAJ by CITF-affiliated expert Dr. Angela Cheung (University of Toronto) and her team discussed how post-COVID-19 condition, otherwise known as long COVID, could be diagnosed in adults. They further discussed some of the potentially modifiable symptoms of long COVID and their treatment strategies. They summarised the findings from multiple studies and highlighted fatigue and general malaise among the most common symptoms of long COVID. Further, they mentioned how through symptom guided programs, people with this condition can mitigate the effects by managing their levels of activity and adopting sleep practices to maximize their rest. Her team’s articles quoted prior studies and mentioned that in time, many people recover, but the actual mechanisms that may contribute to long COVID – including cellular damage, persistent inflammation or the presence of virus in the body, autoimmunity and blood clotting disorders – remain uncertain.
According to the World Health Organization (WHO), long COVID has the following characteristics:
- Symptoms continuing (or starting again) three months after the initial SARS-CoV-2 diagnosis;
- The symptoms last at least 2 months; and
- Symptoms which cannot be explained by an alternative diagnosis.
Nearly 15% of adults in Canada with a suspected or confirmed SARS-CoV-2 infection had symptoms lasting more than 3 months (1). More than 100 symptoms have been associated with long COVID, making diagnosis and treatment challenging (1) .
Diagnosing long COVID in adults (1):
- The 2022 Canadian COVID-19 Antibody and Health Survey reported that nearly 15% of adults (approximately 1.4 million people) in Canada with a suspected or confirmed SARS-CoV-2 infection had symptoms lasting more than three months. According to a recent study (2), this is lower than the global prevalence of long COVID, which is 43%. Long COVID was found to be more prevalent in those who were admitted to hospital (54%) than those who were not (34%) (2). Another study (3) found that, Females (18%) were more likely than males (11.6%) to report lingering symptoms.
- Recent studies (2) (4) have reported more than 100 symptoms in people with long COVID. The most common potentially modifiable symptoms include fatigue (23–63%), anxiety and depression (23–46%), shortness of breath (11–43%), sleep disturbances (11–31%) and palpitations (6–22%).
- Dr. Cheung quoted another study (4) that several pathophysiological mechanisms may contribute to long COVID, including cellular damage, persistent inflammation or the presence of virus in the body, autoimmunity and blood clotting disorders.
- Although many people recover from long COVID, some continue to have symptoms and are unable to return to full-time work a year or more after infection. A recent study from Wuhan, China reported that of those with long COVID, 21% who were previously employed had not returned to work following infection (5). The same proportion of people in Canada reported that their symptoms often or always limited their daily activities (3).
Dr. Cheung collated the ways to assess common and potentially modifiable symptoms of long COVID in adults (6):
- Fatigue, the most common symptom of long COVID, is associated with reduced energy, general feelings of malaise, and generalized exacerbation of other symptoms.
- People with long COVID frequently experience anxiety or depression. It is important to validate a person’s psychological experience during long COVID and to screen for these common symptoms.
- Assessment of difficulty breathing or shortness of breath on exertion should be done during a physical examination, including a walk test for oxygen saturation monitoring.
- Evaluation of sleep disturbances should explore sleep patterns, duration, quality, frequency of awakening, and whether the person feels refreshed after sleeping. Special attention needs to be paid to the use of alcohol, cannabis, caffeine, and sleep medications by people with long COVID. Severe acute illness may warrant a sleep study. The need for supplemental oxygen owing to nocturnal hypoxemia was reported in 6.6% of people who were admitted to the hospital 60 days after acute COVID-19, and may persist beyond 90 days.
- Investigation of palpitations Heart palpitations are feelings of having a fast-beating, fluttering or pounding heart. should include orthostatic vital signs and a 12-lead electrocardiogram. Cardiac dysautonomia Dysautonomia is a disorder of the autonomic nervous system (ANS) function. The ANS is in charge of involuntary functions—things that happen without thinking. has been associated with long COVID. Holter monitoring may help distinguish inappropriate sinus tachycardia Tachycardia is the medical term for a heart rate over 100 beats a minute. (the most common arrhythmia associated with long COVID) from other arrhythmias.
Treating common and potentially modifiable symptoms of long COVID in adults (7):
- Fatigue should be treated with energy conservation strategies. To avoid precipitating post-exertional malaise, patients should be advised to begin a structured and symptom-guided return to activity program tailored to their severity of fatigue.
- Guideline-directed use of psychosocial interventions and medications can be used to treat mental health complications from long COVID. These guidelines are similar to recommendations among people with chronic fatigue syndrome, which is another long-term condition with a wide range of symptoms, the most common of which is extreme tiredness.
- Breathing exercises, body positioning and pulmonary rehabilitation may improve shortness of breath.
- People with sleep disturbances should receive counselling on sleep hygieneHabits and practices that are conducive to sleeping well on a regular basis, relaxation techniques and stimulus control. Sleep can be managed using cognitive behavioural therapy or a prescribed medication.
- Specific guidelines exist for the treatment of palpitations and tachycardia with particular causes. Current recommendations for the treatment of inappropriate sinus tachycardiaSinus tachycardia is a type of irregular heartbeat that is characterized by a faster-than-normal heart rhythm. and postural orthostatic tachycardia syndromePoTS is an abnormal increase in heart rate that occurs after sitting up or standing. Some typical symptoms include dizziness and fainting. include behavioural modifications, oral fluids, salt, compression stockings, β-blockers, ivabradine and midodrine.
- Quinn KL, Razak F, Cheung AM. Diagnosing post-COVID-19 condition (long COVID) in adults. Canadian Medical Association Journal. 2023;195(2):E78-E9.
- Chen C, Haupert SR, Zimmermann L, Shi X, Fritsche LG, Mukherjee B. Global prevalence of post-coronavirus disease 2019 (COVID-19) condition or long COVID: a meta-analysis and systematic review. The Journal of Infectious Diseases. 2022;226(9):1593-607.
- Frequency and impact of longer-term symptoms following COVID-19 in Canadian adults. Ottawa: Government of Canada; 2022. Available: https://health-infobase.canada.ca/covid-19/post-covid-condition/results.html (accessed 2022 Oct. 24)
- Nalbandian A, Sehgal K, Gupta A, Madhavan MV, McGroder C, Stevens JS, et al. Post-acute COVID-19 syndrome. Nature Medicine. 2021;27(4):601-15.
- Huang L, Li X, Gu X, Zhang H, Ren L, Guo L, et al. Health outcomes in people 2 years after surviving hospitalisation with COVID-19: a longitudinal cohort study. The Lancet Respiratory Medicine. 2022;10(9):863-76.
- Quinn KL, Razak F, Cheung AM. Assessing common and potentially modifiable symptoms of post-COVID-19 condition (long COVID) in adults. Canadian Medical Association Journal. 2023;195(2):E76-E7.
- Quinn KL, Cheung AM, Razak F. Treating common and potentially modifiable symptoms of post-COVID-19 condition (long COVID) in adults. Canadian Medical Association Journal. 2023;195(2):E80-E1.