Long COVID

Introduction[edit | edit source]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that causes coronavirus disease (COVID-19) [1]. The effects of COVID-19 have been characterised across different time points:

  • acute COVID-19 infection with signs and symptoms of COVID-19 for up to 4 weeks.
  • ongoing symptomatic COVID-19 with signs and symptoms of COVID-19 from 4 weeks up to 12 weeks.
  • long-term consequences of COVID-19 which usually presents with clusters of symptoms, often overlapping, which can fluctuate and change over time and can affect any system in the body for more than 12 weeks.[2]

** The name Long COVID acknowledges that the disease cause and course are as yet unknown makes clear that “mild” COVID-19 is not necessarily mild, avoids “chronic,” “post” and “syndrome” that may delegitimise people's experiences, draws attention to morbidity, and centres people with disability.[3]

"People call Long COVID by many names, including post-COVID conditions, long-haul COVID, post-acute COVID-19, long-term effects of COVID, and chronic COVID."[4]

What is Long COVID?[edit | edit source]

Long Covid has been preliminarily defined as the presence of signs and symptoms that develop during or following an infection consistent with COVID-19 which continue for 12 weeks or more and are not explained by an alternative diagnosis. This includes both ongoing symptomatic COVID-19 (from 4 to 12 weeks) and "Post-COVID Syndrome" (12 weeks or more).[5]

Long COVID affects people who have been hospitalised with acute COVID-19 and those who managed in a community setting. There is growing evidence to suggest that individuals who have had both mild or severe COVID-19 can experience prolonged symptoms or develop Long COVID.[6][7][8][9][10][11][12][13][14] Long COVID is both common and debilitating.[15]

As of October 2021, the World Health Organization (WHO) has developed a case definition of post COVID-19 condition.

"Post-COVID-19 condition occurs in individuals with a history of probable or confirmed SARS-CoV-2 infection, usually 3 months from the onset of COVID-19 with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis. Common symptoms include fatigue, shortness of breath, cognitive dysfunction but also others* and generally have an impact on everyday functioning. Symptoms may be new onset following initial recovery from an acute COVID-19 episode or persist from the initial illness. Symptoms may also fluctuate or relapse over time."[16]

Long COVID Symptoms[edit | edit source]

Long COVID usually presents as clusters of symptoms, often overlapping, which can fluctuate and change over time and can affect any system in the body. [15][5][17][18][19][20][21] including, but not limited to pulmonary, cardiovascular, gastrointestinal, reproductive, genitourinary, endocrine, renal, dermatologic, musculoskeletal, neurological, neuropsychiatric, immunological, ophthalmic, and audiological.[17]

The most common Long Covid symptom is fatigue.[17][18][22][23][14][24][25][26][10][27][28][29][30][31][32][12][33][34] The most frequently reported Long COVID symptoms after 6 months include fatigue, post-exertion malaise, and cognitive dysfunction.[17] Mental health symptoms associated with long COVID include anxiety (28% increase), increased presence of depression (13% increase), PTSD (20% increase), suicide ideation (10% increase) and decreased life satisfaction and daily functioning. Researchers and patients have distinguished more than 200 symptoms associated with long COVID.[35] The most common symptoms include:

  • tiredness
  • brain fog
  • cough
  • loss of smell or change in taste
  • fever
  • body aches
  • trouble sleeping
  • mood changes[36]

The multidimensional, episodic and often unpredictable nature of Long COVID has been described as "relapsing and remitting",[19] whereby 86% of people with Long COVID report relapses over 7 months, with physical activity, stress, exercise and mental activity being the most common triggers of relapses.[17] The trajectory of Long COVID is heterogenous with some improving over time, some worsening and others stable, with many experiencing ongoing fluctuating symptoms after 6 months.[17][37] Furthermore, outcomes are worse in working-age females than males, with females under 50 being over five times more likely to report incomplete recovery, over five times more likely to report a new disability, more likely to have severe fatigue, and more than six times more likely to report increased breathlessness than males under 50.[37] It is estimated that 30% of people not hospitalised with "mild" acute symptoms, continue to have symptoms 9 months after infection.[12] Preliminary evidence suggests children also experience Long COVID symptoms similar to adults.[38]

[39]

Long COVID Prevalence[edit | edit source]

The COVID-19 Infection Survey[40] is a nationally representative sample of the UK community population, from which it has been estimated that around 1 in 5 people exhibit Long COVID symptoms for 5 weeks or longer, and around 1 in 10 exhibit Long COVID symptoms for 12 weeks or longer.[41][42]

Researchers have determined that Long COVID is more severe and common in individuals infected before the Omicron variant in 2021 and those who were unvaccinated. Additionally, reinfections were related to higher Long COVID severity and frequency compared to people who were only infected once.[35]

Pathological Process[edit | edit source]

The aetiology and pathophysiological causes of Long COVID symptoms remain unknown. Initial hypothesis includes: viral persistence,[43][44][45][46] continued hyperactive immune response,[47][48][49] cellular metabolic dysfunction,[50] auto-antibodies,[51][52] neurological dysfunction,[53][54][55][56] neuroimmunology,[57] neurological inflammation,[58] and organ impairment,[14] including cardiac impairment.[14][59][60][61][62][63] Musculoskeletal short- and long-term consequences of COVID-19 are also discussed.[64] More research is required to understand the mechanisms by which Long COVID develops.[15]

Long COVID Management[edit | edit source]

Currently, there is no evidence from randomised controlled trials on the effectiveness of rehabilitation for Long COVID. Most recommendations from international guidance on rehabilitation for Long COVID are based on expert opinion or evidence from other diseases. Suggestions include patient-centred management with continuous follow-up to decrease the severity of current symptoms. Attention should be placed on creating therapeutic alliances and setting reasonable goals and expectations through discussions with patients and caregivers.[65]

A multi-disciplinary approach to the assessment and management of Long COVID is essential.[15] The team approach could include a rehabilitation physician along with multiple speciality physicians, occupational therapists, physiotherapists, pharmacists, nursing professionals, mental health experts, community workers and other health care professionals.[66] Encompassing a disability model could improve clinicians’ responses to Long COVID.[67]

Rehabilitation professionals should screen for cognitive, physical, emotional and social triggers. The focus of rehabilitation is optimising function, mitigating disability and establishing strategies to support living with a disability. Healthcare professionals need to support people living with Long COVID in managing and anticipating their setbacks. Individuals living with Long COVID need to be heard and understood by their healthcare professionals. Thus, rehabilitation professionals should create a supportive environment, be non-judgmental and respectful that the Long COVID patient is the expert in their health. It is important not to blame the patient for setbacks or exacerbations and to celebrate small successes.[68]

Evaluation and Treatment[edit | edit source]

Rehabilitation professionals should initiate evaluations by ruling out red flags such as exertional desaturation, cardiac impairment, PESE (post-exertional symptom exacerbation) and orthostatic intolerance. PESE refers to the worsening of symptoms immediately or 12-72 hours after exertion and can last for hours to weeks. These symptoms can include fatigue, pain, dyspnoea and cognitive impairment. Individuals with PESE should monitor their duration, intensity and onset of symptom exacerbations and identify potential triggers. An energy conservation technique is suggested to decrease exacerbations. Increasing rehabilitation intensity without considering PESE should be avoided. Individuals with orthostatic intolerance symptoms such as dizziness, breathlessness, presyncope or syncope after a prolonged period in an upright position should be identified.[65]

Mental health problems, psychological therapy, pharmacological therapy and sleep disorders are additional areas that can be addressed in treatment. Some techniques for these issues have included mindfulness-based stress reduction and exercise training. Cognitive impairments can be addressed with environmental modification, pacing and assistive tools, and vital cognitive exercise.[65]

Exercise Therapy[edit | edit source]

There is currently insufficient evidence on safe and effective interventions for the management of Long COVID symptoms and impairments or disability. But the World Health Organization has called on countries to offer people living with Long COVID more rehabilitation.[69]

Rehabilitation must always be safe and effective for the patient. With Long COVID, we should note that exercise is not always medicine. Sometimes rest is medicine.[70]

Physiotherapists often use graded exercise therapy (GET) to progress patients, but this may make post-exertion malaise worse.[70] The National Institute for Health and Care Excellence (NICE) has, for instance, cautioned against the use of GET for managing post-viral fatigue[71] in response to draft guidance updates on the management of Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS).[72][73]

  • Substantial concerns exist regarding the potential for harm with respect to GET as an intervention for ME/CFS.[74]
  • Post-exertion malaise is a symptom experienced by people living with ME/CFS,[75] and is characterised as the worsening of symptoms by exertion including physical, cognitive and emotional activities,[76][77][78] which would prohibit exercise interventions.
  • Among a sample of 3,762 people living with Long COVID, post-exertion malaise was reported by 72.2%.[72] Moreover, exercise is a common trigger for symptom relapses.[17][79]

We must, therefore, be careful when using exercise as a rehabilitation intervention for Long COVID and people living with COVID-19. Groups representing people living with Long COVID have advocated for a risk stratification approach to exercise as a rehabilitation intervention. A focus is needed on assessing and excluding post-exertion malaise,[80][81] plus screening for potential cardiac involvement.[82] We can use the DePaul Symptom Questionnaire to screen for post-exertion malaise.[81] If this symptom is present, exercise may not be considered a safe rehabilitation intervention.[72]

Activity management or pacing and heart rate monitoring are, however, likely to be a safe and effective intervention for managing fatigue and post-exertion malaise. Useful resources on specific rehabilitation ideas, pacing and heart rate monitoring are provided below:

Outcome Measures[edit | edit source]

Some studies have performed a level of functional assessment, including:

Peer Support[edit | edit source]

Peer support involves people sharing knowledge, experience, or practical help with each other, often when living with the same or similar health conditions. Many online Long COVID peer support groups have been established for people living with Long COVID. These are safe spaces for people living with Long COVID to access peer support. Mutual respect and confidentiality are, therefore, requested in these groups. Many of these groups have outputs to share valuable information with allies. Long COVID Physio published blogs with JOSPT highlighting the value of peer support. Long COVID groups include:

Video Resources for Patients[edit | edit source]

References[edit | edit source]

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