Long-term effects of COVID-19

New studies correlate the disease to persistent symptoms, 

from cognitive impairment to sexual dysfunction

By Marianne Bechara

The long-term effects of COVID-19 are a matter of concern for care specialists. Defined by the World Health Organization (WHO) as symptoms that endure or reappear three months after an individual becomes ill because of the coronavirus (SARS-CoV-2), they constitute a situation called “post-COVID-19 condition” or “long COVID”. 

These persistent effects are the main subject of several studies worldwide, including two recent articles: “Cognitive impairment 13 months after hospitalization for COVID-19” and “Symptoms and risk factors for long COVID in non-hospitalized adults”. The papers bring significant findings about the lasting symptoms of COVID-19, such as cognitive damage, loss of hair and smell, and sexual dysfunction.

Published in the journal “Open Forum Infectious Diseases”, the first research, conducted by the University of Oslo, focuses on the cognitive function of 75 patients – with a minimum age of 18 years old – 13 months after their hospital discharge. To obtain accurate results, the scientists utilized four tests: Delayed Matching to Sample (DMS), for “short-term memory, visuospatial processing, learning, and attention”; One Touch Stockings of Cambridge (OTS), to test “executive function, including higher-level thinking and decision-making processes”; Rapid Visual Information Processing (RVP), regarding “sustained attention”; and Spatial Working Memory (SWM), for “working memory and strategy”.

The article reveals that 40 participants (i.e., 53% of the total patients) presented cognitive impairment on one or more tests. On the DMS, the prevalence was 19 of 75 patients (25%); on the OTS, 18 of 75 (24%); on the RVP, 15 of 73 (21%); and, on the SWM, 10 of 74 (14%). It is important to notice, however, that these outcomes can also be related to other causes, such as comorbidities and psychological sequelae.

Led by the University of Birmingham, the second study was published in the peer-reviewed journal “Nature Medicine”. The authors examined primary health data in the United Kingdom – from 31 January 2020 to 15 April 2021 –, in order to understand the persistent effects of COVID-19 among non-hospitalized adults.

Considering the selected database, 486,149 outpatients had a history of infection caused by the coronavirus, while 8,030,224 did not present records of COVID-19. In this last group, 1,944,580 people showed a compatible score with individuals infected by the coronavirus in terms of sociodemographic factors, body mass index (BMI), comorbidities, smoking behavior, and symptoms.

When comparing those who survived COVID-19 to the members of the other group (composed of 1,944,580 profiles), the researchers discovered that the first cohort had a higher chance to display more than one effect related to COVID-19 after 12 weeks. In the case of only one symptom, the rate was 5.6% (for COVID-19 survivors) to 4.7% (for non-infected individuals); concerning two symptoms, 3.6% to 2.9%; and regarding three or more, 4.9% to 4.0%.

Given the many enduring effects of COVID-19, 62 symptoms were found to be more common in the scope of the study. Loss of hair and smell, sneezing, chest pain, fatigue, and sexual dysfunction are among them. The authors also explain that comorbidities – including Chronic Obstructive Pulmonary Disease (COPD), fibromyalgia, depression, multiple sclerosis, and celiac disease – can be responsible for extending the effects of the disease.

In both articles, the authors affirm that further research is necessary to support and enlarge their findings. Nevertheless, the current results are already valuable, since they can help care professionals to comprehend, with more precision, the long-term symptoms analyzed. Because of these and other discoveries, new approaches may be established for the treatment of patients with a post-COVID-19 condition, which will certainly enhance medical practices across the globe.


“Cognitive impairment 13 months after hospitalization for COVID-19”:


“Long COVID – long-term effects of COVID-19”:


“Persistent brain fog, hair loss highlighted in long-COVID studies”:


“Symptoms and risk factors for long COVID in non-hospitalized adults”:


“Tackling the science behind the long-term effects of COVID-19”:

Newsletter Sign Up

To get our free biweekly newsletter. Receive information about Latin American news in BC and in the world..