Eight out of 10 COVID-19 patients had at least one persistent symptom from 14 days to 16 weeks after acute infection, although some effects could last longer. It is the main conclusion that we have drawn from a meta-analysis that can be consulted in this prepublication of medRxiv.
In this work we analyze almost 19,000 studies that uncovered 55 effects persistent after acute infection. The data was drawn from the records of 47,910 people aged 17 to 87 who participated in 15 studies that had evaluated symptoms or long-term laboratory parameters. Each study had a minimum of 100 patients. Nine studies were from Great Britain or Europe, three were from the US, and the rest were from Asia and Australia. Six studies focused only on people hospitalized for COVID-19; the others included mild, moderate and severe cases.
A previous study in Wuhan (China) and published in The Lancet, showed that 76% of the patients who required hospitalization reported at least one symptom 6 months later, and the proportion was higher in women. The most common symptoms were muscle fatigue or weakness and difficulty sleeping. Additionally, 23% reported anxiety or depression during follow-up.
What we know about the previous coronaviruses, SARS and MERS, is that they both share clinical characteristics with COVID-19, including persistent symptoms. The people who survived the SARS showed lung abnormalities months after infection and 28% of people had lung dysfunction up to two years later.
Regarding psychological symptoms, high levels of depression, anxiety and disorder have also been reported. posttraumatic stress long-term in patients previously infected with other coronaviruses. In the case of the survivors of MERS, 33% of people with pulmonary fibrosis, as well as long-term post-traumatic stress and anxiety disorders, were also seen.
The effects of the The most commonly identified long-term COVID-19 were fatigue (58%), headache (44%), attention deficit disorder (27%), hair loss (25%), dyspnea (24%), or anosmia ( 24%).
Other persistent symptoms were pulmonary (cough, chest tightness, decreased lung diffusion capacity, sleep apnea, pulmonary fibrosis), cardiovascular (arrhythmias, myocarditis), neurological or psychiatric (memory loss, depression, anxiety, sleep disorders) . During follow-up, 34% of the patients had an abnormal chest X-ray. Elevated blood markers were also observed that could be used as a prognosis for the disease.
The hair loss it is found in 25% of cases after COVID-19 and could be considered telogen effluvium, defined as diffuse hair loss after a major stressor or systemic coronavirus infection. It is caused by premature follicular transitions from the active growth phase to the resting phase, lasts about 3 months, but can cause emotional distress and trigger neurological diseases.
Loss of taste or smell is transient during the acute phase of COVID-19, but it is true that the records we found indicate that it can be persistent for approximately one year. twenty% of cases and last up to at least 4 months. Experts recommend treating olfactory dysfunctions caused by the coronavirus through vitamin A drops, steroids, but mainly with a olfactory training, which regenerates olfactory neurons damaged by COVID-19 and helps them recover faster.
The SARS-CoV-2 neuroinvasion can affect the brain and leave sequelae at the neurological level. In addition to the direct entry of the coronavirus into the nervous system, either via the olfactory nerve, or by its circulation through the blood system, there are other neurological problems that arise from inflammation and hypercoagulation that occurs in the development of this disease .
Neurocognitive disabilities associated with viral diseases that cause dysfunction in the immune and metabolic systems, as occurs in COVID-19, have already been observed. People with neuropsychiatric problems have a high risk of mortality by COVID-19, but there are also factors that can be the answer to subsequent neuropsychiatric problems. An early diagnosis of psychiatric problems is very important to be able to receive treatment, and to be considered as risk groups in this disease.
There is a need for prospective studies. The Centers for Disease Control and Prevention They aim to identify how common these symptoms are, who is most likely to have them, and if they eventually resolve. More studies are also necessary to determine if some of the symptoms, especially the psychological ones, are due directly to the virus or to the stressful situation of facing the pandemic or to the side effects of intubation and treatments.
To date, there is no established diagnosis for the persistent condition of COVID-19. Therefore, preventive measures, rehabilitation techniques, and clinical management strategies designed to address long-term effects are urgently needed. From a clinical perspective, the need for multidisciplinary teams with complete patient perspectives to address long-term care for COVID-19, monitoring the duration and treatment of each symptom and following up to determine whether these long-term effects term complicate previous illnesses, are a continuation of COVID-19, or may trigger other illnesses in the future.
Sonia Villapol is an associate professor at the Methodist Hospital Research Institute in Houston.