Long COVID: returning athletes from the deep

As the COVID-19 pandemic poses a great public health challenge. While the initial virus infection stressed every country’s healthcare system, a secondary health problem has emerged. Dr. Ryan Frerichs explores Long COVID and uncovers the assessment and management.

Soon after the pandemic, recovered patients began complaining of complications beyond the initial acute infection period. The incidence of Long COVID is high, with 25% of individuals reporting symptoms for more than one month and 10% experience symptoms beyond 12 weeks⁽¹⁾.

Definition

The NICE guidelines define Long COVID as continuous and prolonged symptoms beyond one to three months post-acute viral infection⁽²⁾. To diagnose an athlete with Long COVID, the clinician should ensure the symptoms are not a result of an unrelated infection or medical condition. It may be difficult to distinguish from common seasonal infections, and thus a thorough medical assessment is advised.

Signs and Symptoms

The symptoms associated with Long COVID may be systemic and adapt over time (see table 1). However, the most common symptoms described by individuals are fatigue and dyspnoea⁽³⁾.

Table 1: Multi-systemic symptoms associated with Long COVID⁽²⁾.

System	Symptoms
Respiratory	Breathlessness
	Cough
Cardiovascular	Chest tightness
	Chest pain
	Palpitations
Generalized	Fatigue
	Fever
	Pain
Neurological	Cognitive impairment
	Headache
	Sleep disturbance
	Peripheral
	Neuropathy
	Dizziness
	Delirium
Gastrointestinal	Abdominal pain
	Nausea
	Diarrhea
	Anorexia
Musculoskeletal	Joint pain
	Muscle pain
Psychological	Depression
	Anxiety
Ear/nose/throat	Tinnitus
	Earache
	Sore throat
	Dizziness
	Loss of taste/smell
Dermatological	Skin rashes

Pathophysiology

The pathophysiology of Long COVID is currently unknown. The severity of the disease does not influence the risk of developing Long COVID, as mild infections could have persistent effects. However, several different mechanisms are likely responsible, owing to the spread of diverse symptomatology, and currently, two theoretical models exist.

1. Unresolved inflammation

The SARS-COV-2 virus binds to receptors found in the lungs, heart, liver, kidneys, and blood vessels⁽⁴⁾. One cause of inflammation may be systemic viral persistence as viral shedding in the respiratory tract is possible for up to four months post-infection⁽⁵⁾. Viral shedding is also possible in feces, indicating multi-organ involvement⁽⁶⁾.

In addition, a COVID-19 infection may result in B and T cell lymphocyte deficiency which may increase the time taken to resolve inflammation post-infection. The viral persistence and suppressed immune response may lead to unresolved inflammation and contribute to the symptoms and duration of Long COVID^(7,8).

2. Long-term tissue damage

The possibility of multi-organ involvement is high due to viral dissemination. In addition, tissue fibrosis has been demonstrated four months after acute infection, with the lungs and heart at particular risk⁽⁹⁾. For example, researchers at The First Affiliated Hospital of Zhengzhou University in China found pulmonary changes and abnormalities on MRI in 71% of cases three months after an acute infection, and 25% of participants had functional impairments⁽¹⁰⁾. In some cases, CT chest radiography demonstrates long-term lung fibrosis six months post-COVID infection⁽¹¹⁾.

Metabolic abnormalities and structural brain changes may explain the neurological complications associated with Long COVID. The brainstem has higher quantities of receptors with an affinity to SARS-COV-2 than other brain regions⁽¹²⁾. This may lead to neurological and cardiorespiratory dysfunction⁽¹³⁾. In addition, researchers at University Hospital Frankfurt in Germany found cardiac abnormalities and myocardial inflammation on MRI on individuals with persistent symptoms⁽¹⁴⁾.

Assessment and management

Due to the complexity of Long COVID, a multi-disciplinary approach is most beneficial. There is no specific diagnostic test, and the prognosis is challenging. Therefore, a patient-centered approach is advantageous⁽⁴⁾. The World Health Organization recommends that rehabilitation includes education on the conservative resumption of daily activities and submaximal pacing that is safe and manageable⁽¹⁾. To best guide the management, four groups have been identified (see table 2).

Table 2: A summary of the classification, assessment, and management of Long COVID⁽¹⁾.

Classification	Description	Symptoms	Assessment	Management
Post-exertional symptom exacerbation	The experience of fatigue or exhaustion that results from previously tolerated activity.	Fatigue and exhaustion	Self-report questionnaire	Pacing
		Cognitive dysfunction	Two-day cardiopulmonary exercise testing (CPET)	Heart rate monitoring
		Pain	Six-minute walk test
		Fever	Activity monitors
		Sleep-disturbance
		Diarrhea
		Exercise intolerance
Cardiac impairment	Exacerbation of cardiac-related symptoms on the resumption of physical activity.	Tachycardia	Physical Activity Readiness Questionnaire for Everyone	Referral to cardiologist
		Chest Pain	Physical Activity Readiness Medical Questionnaire	Echocardiogram (ECG)
		Dyspnoea		Holter monitor
		Hypoxia		Echocardiography
		Palpitations		Cardiac MRI
		Exercise intolerance
Exertional oxygen desaturation	A fall of >3% in oxygen saturation during or after mild exertion.	Hyperventilation	Pulse-oximetry monitor	Saturation monitoring
		Increased tidal volume on exertion	The monitoring of oxygen saturation on a 40-step walk and the one-minute sit-stand test	Pacing
		Oxygen desaturation >3%
		Chest pain
		Fatigue
		Dizziness
		Syncope (fainting)
Autonomic nervous system dysfunction	A change in the autonomic nervous system that affects health.	Postural orthostatic tachycardia syndrome (POTS)	NASA-10-minute lean test	Pacing
		Orthostatic intolerance	Active stand test	Autonomic conditioning therapy (Breathwork, supine exercises, symptom titrated submaximal aerobic exercise)
		Breathlessness	COMPASS 31 score
		Fatigue	Heart rate variability, heart rate recovery, and heart rate acceleration
		Pre-syncope (feeling faint)
		Palpitations	It is essential to exclude myocarditis, pneumonia, or pulmonary embolism.

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What is pacing?

Pacing is an approach to managing activity levels with rest to avoid worsening symptoms. Pacing includes identifying realistic goals, monitoring physical, cognitive, and social activities and their effects on energy levels, and avoiding over-exertion⁽¹⁾. An empathetic therapeutic relationship is vital to facilitate the engagement of the athlete in the rehabilitation process. Practitioners need to be receptive and include an athlete’s beliefs and experiences into the rehabilitation care plan. To stabilize symptoms, a holistic approach, which includes rest, sleep management, and appropriate nutrition, is key to rehabilitation success⁽¹⁾. Valuable resources on pacing are available from the Long COVID Physio website.

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Before starting rehabilitation, in persistent symptoms, the first step is to rule out other medical conditions. For example, individuals recovering from an acute COVID infection are at increased risk of developing new cardiovascular and respiratory diseases⁽¹⁵⁾. The screening and assessment of an athlete before return to activity will assist in avoiding a ‘relapse’ and worsening of symptoms. It will also provide the clinician and athlete with a framework to develop realistic goals and care plans. While validated initially for use in chronic fatigue syndrome, the DePaul Symptom Questionnaire covers many chronic symptoms and provides practitioners with an easy-to-use assessment tool (see figure 1)⁽¹⁶⁾.

Practitioners need to continuously monitor and adjust physical activity according to symptoms⁽¹⁷⁾. While graded exercise return has been a cornerstone for other rehabilitation, it is not recommended for chronic fatigue, similarly for Long COVID⁽¹⁸⁾. Instead, practitioners should advise strategies to control and limit the symptoms, adequate pacing, and teach flexibility to allow schedule changes and activity modification. An adaptable, not a graded, approach should allow pacing without pushing through symptoms and rest when appropriate. Due to the risk of worsening symptoms, practitioners should apply interventions with caution, and the aim should be sustainable symptom stabilization to improve daily functioning over time.

Figure 1: A Brief Questionnaire to Screen for Post-Exertional Symptom Exacerbation⁽¹⁹⁾.



A score of 2 on both frequency and severity on any items 1 to 5 indicates post-exercise malaise. The five supplemental questions are also available to examine and monitor the duration, recovery, and exercise exacerbation.

Conclusion

Long COVID is a new and complex condition that requires the attention of public health and sports medicine practitioners globally. As further evidence emerges, the management of Long COVID is likely to improve, but we need to provide athletes with authentic care options until then. One of the keys to successful management is recognizing the signs and symptoms and ensuring that it is safe to proceed. The safe implementation of physical activity interventions requires informed clinical decision-making, carefully planned rehabilitation strategies, and constant symptom monitoring.

References

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