Impact of COVID-19 on neurological, psychological and other mental health outcomes

Last updated

There is increasing evidence suggesting that COVID-19 causes both acute and chronic neurological [1] or psychological symptoms. [2] Caregivers of COVID-19 patients also show a higher than average prevalence of mental health concerns. [2] These symptoms result from multiple different factors.

Contents

SARS-Coronavirus-2 (SARS-CoV-2) directly infects olfactory neurons (smell) and nerve cells expressing taste receptors. Although these cells communicate directly with the brain, the virus does not exhibit strong infection of other nerve cells in the central nervous system. Many of the neurological sequelae appear to result from damage to the vascular cells of the brain or from damage resulting from hypoxia (i.e., limitations in the oxygen supply for the brain). Chronic effects of COVID-19 can lead to a prolonged inflammatory state, which can increase symptoms resembling an autoimmune disorder. [1] Many patients with COVID-19 experience psychological symptoms that can arise either from the direct actions of the virus, the chronic increase in inflammation or secondary effects, such as post-traumatic stress disorder. [2]

Large community-based testing has also found small but measurable average post-infection cognitive deficits, with larger effects among people who report ongoing symptoms and after more severe or earlier-variant infections. [3]

SARS-CoV-2 can be detected in the brain and cerebrospinal fluid acutely by polymerase chain reaction, and is thought to enter via the olfactory system. [4] Cranial nerve (including facial nerve and vagus nerve, which mediate taste) provides an additional route of entry. [4] SARS-CoV-2 has been detected in endothelial cells by electron microscopy, although such a method provides evidence that demonstrates the presence of the virus, but does not convey the amount of virus that is present (qualitative rather than quantitative). [4]

Acute neurologic symptoms

The fraction of subjects who experience symptoms following an infection with SARS-CoV-2 varies by age. Between 10 and 20% of patients who are infected generally exhibit the clinical syndrome, known as COVID-19. The number of COVID-19 infections [5] are highest in subjects between ages 18–65, while the risk of severe disease or death [5] jumps after age 50 and increases with age. About 35% of patients with symptoms of COVID-19 experience neurological complications. [1] [6] Neurological symptoms are not unique to COVID-19; infection with SARS-CoV-1 and MERS-CoV also give rise to acute and delayed neurological symptoms including peripheral neuropathy, myopathy, Guillain–Barré syndrome and Bickerstaff brainstem encephalitis. [7]

Loss of the sense of taste or smell are among the earliest and most common symptoms of COVID-19. Roughly 81% of patients with clinical COVID-19 experience disorders of smell (46% anosmia, 29% hyposmia, and 6% dysosmia). [1] Disorders of taste occur in 94% of patients (ageusia 45%, hypogeusia 23%, and dysgeusia 26%). Most patients recover their sense of taste or smell within 8 days. [1] Delirium is also a common manifestation of the infection, particularly in the elderly. [8] Recent evidence from a longitudinal study supports an inflammatory basis for delirium. [9] Many patients with COVID-19 also experience more severe neurological symptoms. These symptoms include, headache, nausea, vomiting, impaired consciousness, encephalitis, myalgia and acute cerebrovascular disease including stroke, venous sinus, thrombosis and intracerebral hemorrhage. [1] [4] [10] [11]

Increasing attention has focused on cerebrovascular accidents (e.g., stroke), which are reported in up to 5% of hospitalized patients, and occur in both old and young patients. [1] Guillain–Barré syndrome, acute myelitis and encephalomyelitis have also been reported. [11] Guillain–Barré syndrome arises as an autoimmune disorder, that leads to progressive muscle weakness, difficulty walking and other symptoms reflecting reduced signaling to muscles. [11] The cases of myelitis could arise from direct infection of muscle via local angiotensin-converting enzyme 2, the receptor for SARS CoV-2. [4] COVID-19 can also cause severe disease in children. Some children with COVID-19 who develop Kawasaki disease, which is a multi-system inflammatory syndrome that also cerebrovascular disease and neurologic involvement. [1] [11]

Disorders of smell (olfaction) and taste (gustation)

As mentioned above, many COVID-19 patients suffer from disorders of taste or smell. 41% to 62% of patients (depending on the particular study) have disorders of the sense of smell (olfaction), which can present as anosmia (loss of olfaction), hyposmia (reduced olfaction) or parosmia (distortion of olfaction). [12] However, loss of olfaction is not unique to COVID-19; approximately 13% of patients with influenza also lose olfaction, as do patients with MERS-CoV and Ebola virus. [12] Among the patients with COVID-19, 50% of patients recover olfaction within 14 days, and 89% of patients have complete resolution of their loss of olfaction within 4 weeks. [13] [12] Only 5% of COVID-19 patients experience a loss of olfaction lasting more than 40 days. [12]

Structure of the olfactory epithelium. SARS-CoV-2 infects the support cells (sustentacular cells), which injures the olfactory neurons in the olfactory epithelium leading to loss of smell. New olfactory neurons regenerate from the basal cells. Location of olfactory ensheathing cells (OECs) within the olfactory system.png
Structure of the olfactory epithelium. SARS-CoV-2 infects the support cells (sustentacular cells), which injures the olfactory neurons in the olfactory epithelium leading to loss of smell. New olfactory neurons regenerate from the basal cells.

The SARS-CoV-2 virus appears to attack the olfactory epithelium (sustentacullar or "support" cells), which are the cells that surround and support olfactory receptor neurons. [13] [14] Little if any virus directly infects these neurons themselves. [13] However, SARS-CoV-2 infection of the sustentacullar cells can lead to desquamation (shedding) of the olfactory epithelium, with collateral loss of olfactory receptor neurons and anosmia. [13] However, the olfactory epithelium is continually regenerated, and neurons that are damaged are typically replaced in about 14 days. [13] The nerve cells controlling taste, termed the gustatory nerve cells, turn over even faster, being renewed in about 10 days. [13]

Clinical help exists for patients experiencing disorders of olfaction. Patients who experience of loss of smell for longer than two weeks are recommended to obtain olfactory training. [15] Olfactory training helps to "teach" the new olfactory neurons how to link with the brain so that odors can be noticed and then recognized. [15] Personal accounts of the process of olfactory training post COVID-19 infection have been covered in media outlets such as the New York Times. [16] Patients experiencing loss of smell for more than 2 weeks are also recommended to obtain a referral to an ear nose and throat (ENT) physician. [15] Oral corticosteroid therapy can help, but is optional. [15] alpha-lipoic acid is another remedy that has been proposed, but the accumulated literature on this suggests that it does not improve symptoms or recovery. [15]

Chronic neurologic symptoms

Impact of COVID-19 on neurological and psychiatric outcomes in the subsequent 6 months compared with other respiratory tract infections Impact of COVID-19 on neurological and psychiatric outcomes in the subsequent 6 months compared with other respiratory tract infections.jpg
Impact of COVID-19 on neurological and psychiatric outcomes in the subsequent 6 months compared with other respiratory tract infections
This section is an excerpt from Long COVID § Epidemiology.[ edit ]

Estimates of the incidence and prevalence of long COVID vary widely. The estimates depend on the definition of long COVID, the population studied, [18] as well as a number of other methodological differences, such as whether a comparable cohort of individuals without COVID-19 were included, [19] what kinds of symptoms are considered representative of long COVID, [19] and whether long COVID is assessed through a review of symptoms, through self-report of long COVID status, or some other method. [20]

In general, estimates of long COVID incidence based on statistically random sampling of the population are much lower than those based on certified infection, which has a tendency to skew towards more serious cases (including over-representation of hospitalized patients). Further, since incidence appears to be correlated with severity of infection, it is lower in vaccinated groups, on reinfection and during the omicron era, meaning that the time when data was recorded is important. For example, the UK's Office for National Statistics reported [21] in February 2023 (based on random sampling) that "2.4% of adults and 0.6% of children and young people reported long COVID following a second COVID-19 infection". However, a prospective study by Statistics Canada identified a cumulative incidence of 15% after a first infection, 27% after two infections, and 38% after 3 infections. [22]

An August 2024 review found that the prevalence of long COVID is estimated to be about 6–7% in adults, and about 1% in children. [23] By the end of 2023, roughly 400 million people had or have had long COVID. This may be a conservative estimate, as it is based on studies counting those with specific long COVID symptoms only, and not counting those who developed long COVID after an asymptomatic infection. While hospitalised people have higher risks of getting long COVID, most long-haulers had a mild infection and were able to recover from the acute infection at home. [23]

An April 2022 meta-analysis estimated that the pooled incidence of post-COVID conditions after infection was 43%, with estimates ranging between 9% and 81%. People who had been hospitalised with COVID saw a higher prevalence of 54%, while 34% of nonhospitalised people developed long COVID after acute infection. [18] However, a more recent (April 2024) meta-analysis [24] estimated a pooled incidence of 9%.

In the United States in June 2023, 6% of the population indicated having long COVID, as defined as symptoms that last for 3 months or more. [25] This percentage had stayed stable since January that year, but was a decrease compared to June 2022. [25] Of people who had had a prior COVID infection, 11% indicated having long COVID. A quarter of those reported significant limitation in activity. [25] A study by the Medical Expenditure Panel Survey estimated that nearly 18 million people — had suffered from long COVID as of 2023, building on a study sponsored by the Agency for Healthcare Research and Quality. [26]

In a large population cohort study in Scotland, 42% of respondents said they had not fully recovered after 6 to 18 months after catching COVID, and 6% indicated they had not recovered at all. The risk of long COVID was associated with disease severity; people with asymptomatic infection did not have increased risk of long COVID symptoms compared to people who had never been infected. Those that had been hospitalised had 4.6 times higher odds of no recovery compared to nonhospitalised people. [27]

Long COVID is less common in children and adolescents than in adults. [28] Around 16% of children and adolescents develop long COVID following infection. [29]

A study of 236,379 COVID-19 survivors showed that the "estimated incidence of a neurological or psychiatric diagnosis in the following 6 months" after diagnosed infection was 33.62% with 12.84% "receiving their first such diagnosis" and higher risks being associated with COVID-19 severity. [30] [17]

Neuroinflammation as a result of viral infection (e.g., influenza, herpes simplex, and hepatitis C) has been linked to the onset of psychiatric illness across numerous publications. [31] Coronavirus infections are defined as neurotropic viral infections (i.e., they tend to target the nervous system) which increases the risk of neuroinflammation and the induction of immune system dysfunction. [31] Psychotic disorders are characterized by neuroinflammation, more specifically maternal inflammation, and abnormally high mesolimbic dopamine (DA) signaling. [31] Excess inflammation following a COVID-19 infection can alter neurotransmitter signaling which contributes to development of psychotic and mood related disorders. [31]

A large study showed that post COVID-19, [32] people had increased risk of several neurologic sequelae including headache, memory problems, smell problems and stroke; the risk was evident even among people whose acute disease was not severe enough to necessitate hospitalization; the risk was higher among hospitalized, and highest among those who needed ICU care during the acute phase of the infection. [32] About 20% of COVID-19 cases that pass through the intensive care unit (ICU) have chronic neurologic symptoms (beyond loss of smell and taste). [1] Of the patients that had an MRI, 44% had findings upon MRI, such as a FLAIR signal (fluid-attenuated inversion recovery signal), leptomeningeal spaces and stroke. [1] [15] Neuropathological studies of COVID-19 victims show microthrombi and cerebral infarctions. [1] The most common observations are hypoxic damage, which is attributable to use of ventilators. [6] However, many patients who died exhibited perivascular T cells (55%) and microglial cell activation (50%). Guillain–Barre Syndrome occurs in COVID-19 survivors at a rate of 5 per 1000 cases, which is about 500 times the normal incidence of 1 per 100,000 cases. [1] A related type of autoimmune syndrome, termed Miller-Fisher Syndrome, also occurs. [1]

COVID-19 patients who were hospitalized may also experience seizures. [33] One paper suggests that seizures tend to occur in COVID-19 patients with a prior history of seizure disorder or cerebrovascular infarcts, [34] however no reviews are yet available to provide data on the incidence relative to the general population. Acute epileptic seizures and status epilepticus tend to be the seizures reported. [33] 57% of the cases occur among patients who had experienced respiratory or gastrointestinal symptoms. [33] Although treatment with benzodiazepines would seem to be contraindicated because of the risk of respiratory depression, COVID-19 patients with acute epileptic seizures who are treated have a 96% favorable outcome, while patients with acute epileptic seizures who are not treated appear to have higher rates of mortality (5-39%). [33]

A large scale study of 6,245,282 patients have revealed an increased risk of Alzheimer's disease diagnosis following COVID-19 infection. [35] Many pathways involved in Alzheimer's disease progression are also implicated in the antiviral response to COVID-19, including the NLRP3 inflammasome, interleukin-6, and ACE-2. [36] [37]

Acute psychiatric symptoms

Reported prevalence of mental health disorders vary depending on the study. [38] In one review, 35% of patients had mild forms of anxiety, insomnia, and depression and 13% of patients had moderate to severe forms. [39] Another review reports frequencies of depression and anxiety of 47% and 37%. [40] According to a large meta-analysis, depression occurs in 23.0% (16.1 to 26.1) and anxiety in 15.9% (5.6 to 37.7). [41] These psychological symptoms correlate with blood based biomarkers, such as C-reactive protein, which is an inflammatory protein. [40] Psychiatric symptoms were also associated with severity of COVID-19 infection with those bedridden for an extended period of time having a higher prevalence of depressive and anxiety symptoms. [42]

A case report of acute psychiatric disturbance noted an attempted suicide by a patient who had no prior noted psychiatric problems. [43]

Chronic psychiatric symptoms

A 2021 article published in Nature reports increased risk of depression, anxiety, sleep problems, and substance use disorders among post-acute COVID-19 patients. [32] In 2020, a Lancet Psychiatry review reported occurrence of the following post-COVID-19 psychiatric symptoms: traumatic memories (30%), decreased memory (19%), fatigue (19%), irritability (13%), insomnia (12%) and depressed mood (11%). [44] Other symptoms are also prevalent, but are reported in fewer articles; these symptoms include sleep disorder (100% of patients) and disorder of attention and concentration (20%). [15] These accumulated problems lead to a general (and quantified) reduction in the quality of life and social functioning (measured with the SF-36 scale). [15] There is also increasing evidence to suggest that ongoing psychiatric symptoms, including post-traumatic stress [45] and depression, [46] may contribute to fatigue in post-COVID syndrome.

Pediatric symptoms

Children also exhibit neurological or mental health symptoms associated with COVID-19, although the rate of severe disease is much lower among children than adults. [47] Children with COVID-19 appear to exhibit similar rates as adults for loss of taste and smell. [47] Kawasaki syndrome, a multi-system inflammatory syndrome, has received extensive attention. [1] About 16% of children experience some type of neurological manifestation of COVID-19, such as headache or fatigue. [47] About 1% of children have severe neurological symptoms. [47] About 15% of children with Kawasaki syndrome exhibit severe neurological symptoms, such as encephalopathy. [47] COVID-19 does not appear to elicit epilepsy de novo in children, but it can bring out seizures in children with prior histories of epilepsy. [47] COVID-19 has not been associated with strokes in children. [47] Guilliain Barre Syndrome also appears to be rare in children. [47]

Cognitive symptoms

In September 2024, a human challenge study was published; the study lasted from 6 March 2021 to 11 July 2022, with 36 people assigned to acquire a controlled dose of SARS-CoV-2. [48] The purpose of the study was to more definitively account for confounding factors, potentially exhibited by previous observational studies, as well as self-reporting on cognition performance. None of the volunteers were vaccinated. Among the study participants, 2 were eliminated due to prior infection, 18 showed "sustained viral load", and were designated as "infected", with the remainder designated "uninfected". Of the 11 cognitive tasks administered across multiple sessions, Object Memory, both Immediate and Delayed, yielded the largest differences between the "infected" and "uninfected" groups, with the "infected" group performing worse, particularly in Object Memory Immediate. Cognitive changes were still observed after around one year, and the authors noted that this would likely be the sole human challenge study involving SARS-CoV-2. [49]

In October 2024, a paper published in Nature Translational Psychiatry studied brain and cognitive changes from Italian adolescents and young adults before and after a COVID infection. Participants totaled 13 infected, with 27 serving as controls. The cohort was obtained by convenience sample from another study, which was evaluating the effects of heavy metal exposure in Northern Italy. In addition to MRI scans, the cohort was also tasked with completing the Cambridge Neuropsychological Test Automated Battery (CANTAB). Significant changes in brain volume were observed in certain areas of the brain, especially in areas tasked with smell and cognition, but no significant changes were seen in "whole brain connectivity". [50] [51] The authors of the paper noted that the cognitive test results corroborated previous studies quantifying the impact of COVID-19 on various cognitive functions, but that a study with a larger sample size would be needed to properly account for confounding factors. [50]

A large community study in England (112,964 completers) reported objectively measurable—but generally small—deficits in global cognition after SARS-CoV-2 infection, with larger deficits among people whose symptoms had not resolved ≥12 weeks ("unresolved" persistent symptoms). Estimated standardized differences versus a no-COVID group were about −0.23 to −0.24 SD among those who had recovered (short-duration or resolved persistent symptoms) and −0.42 SD among those with unresolved persistent symptoms. The largest deficits were on memory, reasoning, and executive-function tasks; deficits were greater after infections during earlier variant periods (original/Alpha) than during later periods (e.g., Omicron), and were more pronounced among individuals who had been hospitalized (especially ICU). The longer-term persistence and clinical significance remain uncertain. [3]

Research into COVID-19 induced brain damage

Neurological complications in COVID-19 are a result of SARS-CoV-2 infection or a complication of post infection which can be due to (1) direct SARS-CoV-2 invasion on the CNS via systemic circulation or olfactory epithelium directed trans-synaptic mechanism; (2) Inflammatory mediated CNS damage due to cytokine storm and endothelitis; (3) Thrombosis mediated CNS damage due to SARS-CoV-2 interaction with host ACE2 receptor resulting in ACE2 downregulation, coagulation cascade activation, and multiple organ dysfunction; (4) Hypoxemic respiratory failures and cardiorespiratory effects due to SARS-CoV-2 invasion on brain stem. [52]

There is ongoing research about the short- and long-term damage COVID-19 may possibly cause to the brain. [38] including in cases of 'long COVID'. For instance, a study showed how COVID-19 may cause microvascular brain pathology and endothelial cell-death, disrupting the blood–brain barrier. [53] [54] Another study identified neuroinflammation and an activation of adaptive and innate immune cells in the brain stem of COVID-19 patients. [55] Brain-scans and cognitive tests of 785 UK Biobank participants (401 positive cases) suggests COVID-19 is associated with, at least temporary, changes to the brain that include: [56]

It has been identified that anosmia present during the acute phase of illness can be a risk factor for developing brain damage. A study revealed that patients recovering from COVID-19 who experienced anosmia during the acute episode exhibited impulsive decision-making, functional brain alterations, cortical thinning, and changes in white matter integrity. [57]

A study indicates that SARS-CoV-2 builds tunneling nanotubes from nose cells to gain access to the brain. [58] [59]

Ethnoracial Disparities in Cognitive Effects of Long COVID

An April 2023 study published in Journal of the National Medical Association performed a quantitative secondary analysis on data collected from the Household Pulse Survey (HHPS) between June and October 2022. 108,000 responses were sampled weekly and were representative with respect to geographic location, race, and gender. A logistic regression analysis was conducted on responses to Phase 3.6 which includes questions on long COVID symptoms, vaccinations, and demographic characteristics. The study found that racial disparities in long COVID prevalence mirror those seen in acute COVID-19. In particular, Blacks and Hispanics were significantly more likely to report long COVID than Whites. Additionally, females also showed a higher likelihood of long COVID compared to males. The study indicated that disparities existed beyond racial and ethnic lines. Individuals with private health insurance and those vaccinated were less likely to report long COVID. Factors such as socioeconomic status, healthcare access, and occupational exposure are critical in understanding these disparities, as they can influence both the likelihood of contracting COVID-19 and the severity of its long-term effects. Overall, an understanding of the social determinants of health is needed to comprehensively address cognitive effects of Long COVID. [60]

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Koralnik IJ, Tyler KL (July 2020). "COVID-19: A Global Threat to the Nervous System". Annals of Neurology. 88 (1): 1–11. doi:10.1002/ana.25807. PMC   7300753 . PMID   32506549.
  2. 1 2 3 Hossain MM, Tasnim S, Sultana A, Faizah F, Mazumder H, Zou L, et al. (2020). "Epidemiology of mental health problems in COVID-19: a review". F1000Research. 9: 636. doi: 10.12688/f1000research.24457.1 . PMC   7549174 . PMID   33093946.
  3. 1 2 Hampshire A, Azor A, Atchison C, Trender W, Hellyer PJ, Giunchiglia V, Husain M, Cooke GS, Cooper E, Lound A, Donnelly CA, Chadeau-Hyam M, Ward H, Elliott P (2024-02-29). "Cognition and Memory after Covid-19 in a Large Community Sample". The New England Journal of Medicine. 390 (9): 806–818. doi:10.1056/NEJMoa2311330. PMID   38416429.
  4. 1 2 3 4 5 Al-Sarraj S, Troakes C, Hanley B, Osborn M, Richardson MP, Hotopf M, et al. (February 2021). "Invited Review: The spectrum of neuropathology in COVID-19". Neuropathology and Applied Neurobiology. 47 (1): 3–16. doi: 10.1111/nan.12667 . hdl: 11343/252622 . PMID   32935873.
  5. 1 2 CDC (2020-03-28). "COVID Data Tracker". Centers for Disease Control and Prevention. Retrieved 2021-03-05.
  6. 1 2 Mukerji SS, Solomon IH (January 2021). "What can we learn from brain autopsies in COVID-19?". Neuroscience Letters. 742 135528. doi:10.1016/j.neulet.2020.135528. PMC   7687409 . PMID   33248159.
  7. ↑ Troyer EA, Kohn JN, Hong S (July 2020). "Are we facing a crashing wave of neuropsychiatric sequelae of COVID-19? Neuropsychiatric symptoms and potential immunologic mechanisms". Brain, Behavior, and Immunity. 87: 34–39. doi:10.1016/j.bbi.2020.04.027. PMC   7152874 . PMID   32298803.
  8. ↑ Barthorpe A, Rogers JP (2021-12-08). "Coronavirus infections from 2002-2021: Neuropsychiatric Manifestations". Sleep Medicine. 91: 282–288. doi:10.1016/j.sleep.2021.11.013. ISSN   1389-9457. PMC   8651478 . PMID   35221210.
  9. ↑ Saini A, Oh TH, Ghanem DA, Castro M, Butler M, Sin Fai Lam CC, Posporelis S, Lewis G, David AS, Rogers JP (2021-10-15). "Inflammatory and blood gas markers of COVID-19 delirium compared to non-COVID-19 delirium: a cross-sectional study". Aging & Mental Health. 26 (10): 2054–2061. doi: 10.1080/13607863.2021.1989375 . ISSN   1360-7863. PMID   34651536. S2CID   238990849.
  10. ↑ Bobker SM, Robbins MS (September 2020). "COVID-19 and Headache: A Primer for Trainees". Headache. 60 (8): 1806–1811. doi:10.1111/head.13884. PMC   7300928 . PMID   32521039.
  11. 1 2 3 4 Harapan BN, Yoo HJ (January 2021). "Neurological symptoms, manifestations, and complications associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 19 (COVID-19)". Journal of Neurology. 268 (9): 3059–3071. doi:10.1007/s00415-021-10406-y. PMC   7826147 . PMID   33486564.
  12. 1 2 3 4 Mastrangelo A, Bonato M, Cinque P (March 2021). "Smell and taste disorders in COVID-19: From pathogenesis to clinical features and outcomes". Neuroscience Letters. 748 135694. doi:10.1016/j.neulet.2021.135694. PMC   7883672 . PMID   33600902.
  13. 1 2 3 4 5 6 Meunier N, Briand L, Jacquin-Piques A, Brondel L, Pénicaud L (2021-01-26). "COVID 19-Induced Smell and Taste Impairments: Putative Impact on Physiology". Frontiers in Physiology. 11 625110. doi: 10.3389/fphys.2020.625110 . ISSN   1664-042X. PMC   7870487 . PMID   33574768.
  14. ↑ Veronese S, Sbarbati A (2021-03-03). "Chemosensory Systems in COVID-19: Evolution of Scientific Research". ACS Chemical Neuroscience. 12 (5): 813–824. doi:10.1021/acschemneuro.0c00788. ISSN   1948-7193. PMC   7885804 . PMID   33559466.
  15. 1 2 3 4 5 6 7 8 Hopkins C, Alanin M, Philpott C, Harries P, Whitcroft K, Qureishi A, Anari S, Ramakrishnan Y, Sama A, Davies E, Stew B (2021). "Management of new onset loss of sense of smell during the COVID-19 pandemic – BRS Consensus Guidelines". Clinical Otolaryngology. 46 (1): 16–22. doi:10.1111/coa.13636. ISSN   1749-4478. PMC   7461026 . PMID   32854169.
  16. ↑ Rao T (2021-03-02). "Will Fish Sauce and Charred Oranges Return the World Covid Took From Me?". The New York Times. ISSN   0362-4331 . Retrieved 2021-03-24.
  17. 1 2 Taquet M, Geddes JR, Husain M, Luciano S, Harrison PJ (1 May 2021). "6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: a retrospective cohort study using electronic health records". The Lancet Psychiatry. 8 (5): 416–427. doi: 10.1016/S2215-0366(21)00084-5 . ISSN   2215-0366. PMC   8023694 . PMID   33836148.
  18. 1 2 Chen C, Haupert SR, Zimmermann L, Shi X, Fritsche LG, Mukherjee B (November 2022). "Global Prevalence of Post-Coronavirus Disease 2019 (COVID-19) Condition or Long COVID: A Meta-Analysis and Systematic Review". The Journal of Infectious Diseases. 226 (9): 1593–1607. doi:10.1093/infdis/jiac136. PMC   9047189 . PMID   35429399.
  19. 1 2 Nasserie T, Hittle M, Goodman SN (May 2021). "Assessment of the Frequency and Variety of Persistent Symptoms Among Patients With COVID-19: A Systematic Review". JAMA Network Open. 4 (5): e2111417. doi:10.1001/jamanetworkopen.2021.11417. PMC   8155823 . PMID   34037731. Archived from the original on 28 April 2024. Retrieved 8 April 2024.
  20. ↑ "Technical article: Updated estimates of the prevalence of post-acute symptoms among people with coronavirus (COVID-19) in the UK - Office for National Statistics". www.ons.gov.uk. 16 September 2021. Archived from the original on 8 April 2024. Retrieved 8 April 2024.
  21. ↑ "New-onset, self-reported long COVID after coronavirus (COVID-19) reinfection in the UK: 23 February 2023". 23 February 2023.
  22. ↑ Government of Canada SC (2023-12-08). "Experiences of Canadians with long-term symptoms following COVID-19". www150.statcan.gc.ca. Retrieved 2025-05-22.
  23. 1 2 Al-Aly Z, Davis H, McCorkell L, Soares L, Wulf-Hanson S, Iwasaki A, Topol EJ (August 2024). "Long COVID science, research and policy". Nature Medicine. 30 (8): 2148–2164. doi: 10.1038/s41591-024-03173-6 . PMID   39122965.
  24. ↑ "New research examines the risk of developing Long Covid". 25 April 2024. Archived from the original on 17 July 2024. Retrieved 17 July 2024.
  25. 1 2 3 Ford ND, Slaughter D, Edwards D, Dalton A, Perrine C, Vahratian A, Saydah S (August 2023). "Long COVID and Significant Activity Limitation Among Adults, by Age – United States, June 1–13, 2022, to June 7–19, 2023". MMWR. Morbidity and Mortality Weekly Report. 72 (32): 866–870. doi:10.15585/mmwr.mm7232a3. PMC   10415000 . PMID   37561665.
  26. ↑ McMahan I (15 July 2024). "About 7 percent of U.S. adults have had long covid, report says". The Washington Post.
  27. ↑ Hastie CE, Lowe DJ, McAuley A, Winter AJ, Mills NL, Black C, Scott JT, O'Donnell CA, Blane DN, Browne S, Ibbotson TR, Pell JP (October 2022). "Outcomes among confirmed cases and a matched comparison group in the Long-COVID in Scotland study". Nature Communications. 13 (1) 5663. Bibcode:2022NatCo..13.5663H. doi:10.1038/s41467-022-33415-5. PMC   9556711 . PMID   36224173.
  28. ↑ Zheng YB, Zeng N, Yuan K, Tian SS, Yang YB, Gao N, Chen X, Zhang AY, Kondratiuk AL, Shi PP, Zhang F, Sun J, Yue JL, Lin X, Shi L, Lalvani A, Shi J, Bao YP, Lu L (May 2023). "Prevalence and risk factor for long COVID in children and adolescents: A meta-analysis and systematic review". Journal of Infection and Public Health. 16 (5): 660–672. doi:10.1016/j.jiph.2023.03.005. PMC   9990879 . PMID   36931142.
  29. ↑ Jiang L, Li X, Nie J, Tang K, Bhutta ZA (August 2023). "A Systematic Review of Persistent Clinical Features After SARS-CoV-2 in the Pediatric Population". Pediatrics. 152 (2) e2022060351. doi:10.1542/peds.2022-060351. PMC   10389775 . PMID   37476923.
  30. ↑ "The early results are in: Two-thirds of Australia's severe COVID sufferers are in for the long haul". www.abc.net.au. 9 May 2021. Retrieved 10 May 2021.
  31. 1 2 3 4 Jansen van Vuren EE, Steyn SF, Brink CB, Möller MM, Viljoen FP, Harvey BH (March 2021). "The neuropsychiatric manifestations of COVID-19: Interactions with psychiatric illness and pharmacological treatment". Biomedicine & Pharmacotherapy. 135 111200. doi:10.1016/j.biopha.2020.111200. PMC   7834135 . PMID   33421734.
  32. 1 2 3 Al-Aly Z, Xie Y, Bowe B (2021-04-22). "High-dimensional characterization of post-acute sequalae of COVID-19". Nature. 594 (7862): 259–264. Bibcode:2021Natur.594..259A. doi: 10.1038/s41586-021-03553-9 . ISSN   1476-4687. PMID   33887749.
  33. 1 2 3 4 Dono F, Nucera B, Lanzone J, Evangelista G, Rinaldi F, Speranza R, Troisi S, Tinti L, Russo M, Di Pietro M, Onofrj M (2021). "Status epilepticus and COVID-19: A systematic review". Epilepsy & Behavior. 118 107887. doi:10.1016/j.yebeh.2021.107887. PMC   7968345 . PMID   33743344.
  34. ↑ Waters BL, Michalak AJ, Brigham D, Thakur KT, Boehme A, Claassen J, Bell M (2021-02-04). "Incidence of Electrographic Seizures in Patients With COVID-19". Frontiers in Neurology. 12 614719. doi: 10.3389/fneur.2021.614719 . ISSN   1664-2295. PMC   7890122 . PMID   33613431.
  35. ↑ Gonzalez-Fernandez E, Huang J (2023-09-01). "Cognitive Aspects of COVID-19". Current Neurology and Neuroscience Reports. 23 (9): 531–538. doi:10.1007/s11910-023-01286-y. ISSN   1534-6293. PMID   37490194. S2CID   260132167.
  36. ↑ Rahman MA, Islam K, Rahman S, Alamin M (March 2021). "Neurobiochemical Cross-talk Between COVID-19 and Alzheimer's Disease". Molecular Neurobiology. 58 (3): 1017–1023. doi:10.1007/s12035-020-02177-w. ISSN   0893-7648. PMC   7571527 . PMID   33078369.
  37. ↑ Wang H, Lu J, Zhao X, Qin R, Song K, Xu Y, Zhang J, Chen Y (December 2021). "Alzheimer's disease in elderly COVID-19 patients: potential mechanisms and preventive measures". Neurological Sciences. 42 (12): 4913–4920. doi:10.1007/s10072-021-05616-1. ISSN   1590-1874. PMC   8455804 . PMID   34550494.
  38. ↑ Mukerji SS, Solomon IH (2021-01-18). "What can we learn from brain autopsies in COVID-19?". Neuroscience Letters. 742 135528. doi:10.1016/j.neulet.2020.135528. ISSN   1872-7972. PMC   7687409 . PMID   33248159.
  39. 1 2 Hossain MM, Tasnim S, Sultana A, Faizah F, Mazumder H, Zou L, McKyer EL, Ahmed HU, Ma P (2020). "Epidemiology of mental health problems in COVID-19: a review". F1000Research. 9: 636. doi: 10.12688/f1000research.24457.1 . ISSN   2046-1402. PMC   7549174 . PMID   33093946.
  40. ↑ Rogers JP, Watson CJ, Badenoch J, Cross B, Butler M, Song J, Hafeez D, Morrin H, Rengasamy ER, Thomas L, Ralovska S (2021-06-03). "Neurology and neuropsychiatry of COVID-19: a systematic review and meta-analysis of the early literature reveals frequent CNS manifestations and key emerging narratives". Journal of Neurology, Neurosurgery & Psychiatry. 92 (9): 932–941. doi: 10.1136/jnnp-2021-326405 . hdl: 20.500.11820/448ac1f4-795d-4cb5-af76-62a8ec36c95c . ISSN   0022-3050. PMID   34083395. S2CID   235334764.
  41. ↑ Magnúsdóttir I, Lovik A, Unnarsdóttir AB, McCartney D, Ask H, Kõiv K, Christoffersen LA, Johnson SU, Hauksdóttir A, Fawns-Ritchie C, Helenius D, González-Hijón J, Lu L, Ebrahimi OV, Hoffart A (2022-05-01). "Acute COVID-19 severity and mental health morbidity trajectories in patient populations of six nations: an observational study". The Lancet Public Health. 7 (5): e406 –e416. doi:10.1016/S2468-2667(22)00042-1. ISSN   2468-2667. PMC   8920517 . PMID   35298894.
  42. ↑ Gillett G, Jordan I (2020). "Severe psychiatric disturbance and attempted suicide in a patient with COVID-19 and no psychiatric history". BMJ Case Reports. 13 (10) e239191. doi: 10.1136/bcr-2020-239191 . PMC   7783370 . PMID   33130587.
  43. ↑ Rogers JP, Chesney E, Oliver D, Pollak TA, McGuire P, Fusar-Poli P, Zandi MS, Lewis G, David AS (July 2020). "Psychiatric and neuropsychiatric presentations associated with severe coronavirus infections: a systematic review and meta-analysis with comparison to the COVID-19 pandemic". The Lancet. Psychiatry. 7 (7): 611–627. doi:10.1016/S2215-0366(20)30203-0. ISSN   2215-0374. PMC   7234781 . PMID   32437679.
  44. ↑ Harenwall S, Heywood-Everett S, Henderson R, Smith J, McEnery R, Bland AR (2022). "The Interactive Effects of Post-Traumatic Stress Symptoms and Breathlessness on Fatigue Severity in Post-COVID-19 Syndrome". Journal of Clinical Medicine. 11 (20): 6214. doi: 10.3390/jcm11206214 . ISSN   2077-0383. PMC   9604889 . PMID   36294534.
  45. ↑ Al-Jassas HK, Al-Hakeim HK, Maes M (2022-01-15). "Intersections between pneumonia, lowered oxygen saturation percentage and immune activation mediate depression, anxiety, and chronic fatigue syndrome-like symptoms due to COVID-19: A nomothetic network approach". Journal of Affective Disorders. 297: 233–245. doi:10.1016/j.jad.2021.10.039. ISSN   0165-0327. PMC   8541833 . PMID   34699853.
  46. 1 2 3 4 5 6 7 8 Boronat S (2021-02-18). "Neurologic Care of COVID-19 in Children". Frontiers in Neurology. 11 613832. doi: 10.3389/fneur.2020.613832 . ISSN   1664-2295. PMC   7935545 . PMID   33679571.
  47. ↑ "SARS-CoV-2 Human Challenge Characterisation Study". 2022-07-28.
  48. ↑ Trender W, Hellyer PJ, Killingley B, Kalinova M, Mann AJ, Catchpole AP, Menon D, Needham E, Thwaites R, Chiu C, Scott G, Hampshire A (2024). "Changes in memory and cognition during the SARS-CoV-2 human challenge study". eClinicalMedicine. 76. doi:10.1016/j.eclinm.2024.102842. PMC   11447363 . PMID   39364271.
  49. 1 2 Invernizzi A, Renzetti S, Van Thriel C, Rechtman E, Patrono A, Ambrosi C, Mascaro L, Corbo D, Cagna G, Gasparotti R, Reichenberg A, Tang CY, Lucchini RG, Wright RO, Placidi D, Horton MK (2024). "COVID-19 related cognitive, structural and functional brain changes among Italian adolescents and young adults: A multimodal longitudinal case-control study". Translational Psychiatry. 14 (1): 402. doi:10.1038/s41398-024-03108-2. PMC   11447249 . PMID   39358346.
  50. ↑ Sushama R. Chaphalkar, PhD, Susha Cheriyedath, M.Sc. (2024-10-03). "Mild COVID-19 disrupts brain connectivity and reduces memory function in adolescents and young adults". AZONetwork News Medical.
  51. ↑ Mathew B, Kumar R, Harilal S, M S, Pappachan LK, PR R (April 2022). "Current Perspective of COVID-19 on Neurology: A Mechanistic Insight". Combinatorial Chemistry & High Throughput Screening. 25 (5): 763–767. doi:10.2174/1386207324666210805121828. ISSN   1386-2073. PMID   34353250. S2CID   236933857.
  52. ↑ "Study reveals how COVID-19 can directly damage brain cells". New Atlas. 25 October 2021. Retrieved 16 November 2021.
  53. ↑ Jan Wenzel, et al. (November 2021). "The SARS-CoV-2 main protease Mpro causes microvascular brain pathology by cleaving NEMO in brain endothelial cells". Nature Neuroscience. 24 (11): 1522–1533. doi:10.1038/s41593-021-00926-1. ISSN   1546-1726. PMC   8553622 . PMID   34675436.
  54. ↑ Schwabenland M, Salié H, Tanevski J, Killmer S, Lago MS, Schlaak AE, Mayer L, Matschke J, Püschel K, Fitzek A, Ondruschka B (2021-06-09). "Deep spatial profiling of human COVID-19 brains reveals neuroinflammation with distinct microanatomical microglia-T-cell interactions". Immunity. 54 (7) (published June 2021): 1594–1610.e11. doi:10.1016/j.immuni.2021.06.002. PMC   8188302 . PMID   34174183.
  55. ↑ Douaud G, Lee S, Alfaro-Almagro F, Arthofer C, Wang C, McCarthy P, Lange F, Andersson JL, Griffanti L, Duff E, Jbabdi S, Taschler B, Keating P, Winkler AM, Collins R, Matthews PM, Allen N, Miller KL, Nichols TE, Smith SM (7 March 2022). "SARS-CoV-2 is associated with changes in brain structure in UK Biobank". Nature. 604 (7907): 697–707. Bibcode:2022Natur.604..697D. doi:10.1038/s41586-022-04569-5. ISSN   1476-4687. PMC   9046077 . PMID   35255491.
  56. ↑ Kausel L, Figueroa-Vargas A (2024). "Patients recovering from COVID-19 who presented with anosmia during their acute episode have behavioral, functional, and structural brain alterations". Scientific Reports. 14 (1): 19049. Bibcode:2024NatSR..1419049K. doi:10.1038/s41598-024-69772-y. PMC   11329703 . PMID   39152190.
  57. ↑ "Coronavirus may enter the brain by building tiny tunnels from the nose". New Scientist. Retrieved 23 August 2022.
  58. ↑ Pepe A, Pietropaoli S, Vos M, Barba-Spaeth G, Zurzolo C (22 July 2022). "Tunneling nanotubes provide a route for SARS-CoV-2 spreading". Science Advances. 8 (29) eabo0171. Bibcode:2022SciA....8O.171P. doi: 10.1126/sciadv.abo0171 . ISSN   2375-2548. PMC   9299553 . PMID   35857849.
  59. ↑ Jacobs MM, Evans E, Ellis C (2023-04-01). "Racial, ethnic, and sex disparities in the incidence and cognitive symptomology of long COVID-19". Journal of the National Medical Association. 115 (2): 233–243. doi:10.1016/j.jnma.2023.01.016. ISSN   0027-9684. PMC   9923441 . PMID   36792456.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.