Trajectory of Post-COVID Self-Reported Fatigue and Dyspnoea in Individuals Who Had Been Hospitalized by COVID-19: The LONG-COVID-EXP Multicenter Study

Risk Factors and Predictors for Persistent Dyspnea Post-COVID-19: A Systematic Review

The most frequently reported post-coronavirus disease of 2019 (COVID-19) symptoms include shortness of breath, fatigue, and cognitive disturbances, with reports of persistent dyspnea ranging between 26% and 41%. There is an urgent need to understand the risk factors and predictors for persistent COVID-19 dyspnea in individuals at all levels of COVID-19 illness severity, to enable the implementation of targeted interventions for those likely to be most affected with persistent dyspnea. Thus, the purpose of this systematic review is to explore the risk factors and predictors that are associated with persistent dyspnea in the post-COVID-19 population. This review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines and registered prospectively in PROSPERO as CRD42023466713. A search strategy was conducted across PubMed, CINAHL, Web of Science, and EMBASE databases, that included studies conducted from 2020 to March 2024. The Covidence platform was used for screening studies, scoring methodologic quality, and performing data extraction using a two-step independent review process. This review included 33 studies, addressing 83,920 participants across 20 countries. The strongest predictive risk factors for persistent dyspnea included the following: female sex, elevated body mass index, pulmonary comorbidities, pre-existing anxiety and depression, pre-COVID-19 physical limitations, the severity of the COVID-19 illness, and socioeconomic differences. Potential risk factors included increased age, smoking history, and COVID-19 variant type. The presence of biomarkers for persistent dyspnea in the post-COVID-19 population can be used by clinicians to prospectively identify those individuals who should be flagged. Early identification may then be leveraged for timely referral for prophylactic and rehabilitative interventions for dyspnea. A personalized plan to target those risk factors that are modifiable should follow.

Persistent disabilities 28 months after COVID-19 hospitalisation, a prospective cohort study

Background

Limited data are available on long-term respiratory disabilities in patients following acute COVID-19.

Patients and methods

This prospective, monocentric, observational cohort study included patients admitted to our hospital with acute COVID-19 between 12 March and 24 April 2020. Clinical, functional and radiological data were collected up to 28 months after hospital discharge.

Results

Among 715 patients hospitalised for COVID-19, 493 (69.0%) were discharged alive. We could access complete medical records for 268 out of 493 patients (54.4%); 138 out of 268 (51.5%) exhibited persistent respiratory symptoms and agreed with the data collection and follow-up. Patients were predominantly male (64.5%), with a mean±sd age of 58.9±15.3 years. At the last follow-up, the leading symptoms were asthenia (31.5%), dyspnoea (29.8%) and neuropsychological symptoms (17.7%). Lung function improved up to the last visit. Mean diffusing capacity of the lung for carbon monoxide (D LCO) was 77.8% of predicted value, total lung capacity (TLC) was 83.5% and O2 desaturation during exercise (O2 desaturation) was 2.3%. While D LCO improved over the entire period, TLC improved in the early phase and O2 desaturation in the late phase. Except for those with lung comorbidities, only one patient presented with minor functional and chest radiological alterations at 28 months.

Conclusion

Patients with acute COVID-19 discharged alive showed improved clinical symptoms, lung function parameters and radiological signs up to 28 months post-infection. Persistent symptoms consisted mainly of asthenia and dyspnoea, with lung function returning to normal. One patient without prior respiratory issues exhibited moderate pulmonary fibrosis.

Impact of Circulating Anti-Spike Protein Antibody Levels on Multi-Organ Long COVID Symptoms

Patients with long COVID syndrome present with various symptoms affecting multiple organs. Vaccination before or after SARS-CoV-2 infection appears to reduce the incidence of long COVID or at least limit symptom deterioration. However, the impact of vaccination on the severity and extent of multi-organ long COVID symptoms and the relationship between the circulating anti-spike protein antibody levels and the severity and extent of multi-organ symptoms are unclear. This prospective cohort study included 198 patients with previous PCR-verified SARS-CoV-2 infection who met the criteria for long COVID syndrome. Patients were divided into vaccinated (n = 138, 69.7%) or unvaccinated (n = 60, 30.3%) groups. Anti-spike protein antibody levels were determined at initial clinical presentation and compared between the groups. Long COVID symptoms were quantified on the basis of the number of affected organs: Class I (mild) with symptoms in three organs, Class II (moderate) with symptoms in four to five organs, and Class III (severe) with symptoms in six or more organ systems. Associations between time to infection and vaccination with anti-spike protein antibody levels were assessed. The anti-spike protein antibody levels were 1925 ± 938 vs. 481 ± 768 BAU/mL (p < 0.001) in the vaccinated vs. unvaccinated patients. The circulating anti-spike antibody cutoff of 665.5 BAU/mL allowed us to differentiate the vaccinated from the unvaccinated patients. Vaccinated patients had fewer class II and class III multi-organ symptoms (Class II 39.9% vs. 45.0%; Class III 10.1% vs. 23.3%, p-value 0.014). Anti-spike antibody level correlated negatively with multi-organ symptom classes (p = 0.016; 95% CI -1.229 to -0.126). Anti-spike antibody levels in unvaccinated patients declined markedly with time, in contrast to the persistence of high anti-spike antibody levels in the vaccinated patients. Multi-organ symptoms were lower in vaccinated long-COVID patients, especially in those with higher anti-spike antibody levels (≥665.5 BAU/mL). Classifying the symptoms on the basis of the number of affected organs enables a more objective symptom quantification.

Pathophysiological, immunological, and inflammatory features of long COVID

The COVID-19 pandemic continues to cause severe global disruption, resulting in significant excess mortality, overwhelming healthcare systems, and imposing substantial social and economic burdens on nations. While most of the attention and therapeutic efforts have concentrated on the acute phase of the disease, a notable proportion of survivors experience persistent symptoms post-infection clearance. This diverse set of symptoms, loosely categorized as long COVID, presents a potential additional public health crisis. It is estimated that 1 in 5 COVID-19 survivors exhibit clinical manifestations consistent with long COVID. Despite this prevalence, the mechanisms and pathophysiology of long COVID remain poorly understood. Alarmingly, evidence suggests that a significant proportion of cases within this clinical condition develop debilitating or disabling symptoms. Hence, urgent priority should be given to further studies on this condition to equip global public health systems for its management. This review provides an overview of available information on this emerging clinical condition, focusing on the affected individuals' epidemiology, pathophysiological mechanisms, and immunological and inflammatory profiles.

Persistence of post-COVID symptoms in the general population two years after SARS-CoV-2 infection: A systematic review and meta-analysis

OBJECTIVE

This meta-analysis investigated the prevalence of post-COVID symptoms two-years after SARS-CoV-2 infection.

METHODS

Electronic literature searches on PubMed, MEDLINE, CINAHL, EMBASE, Web of Science databases, and on medRxiv/bioRxiv preprint servers were conducted up to October 1, 2023. Studies reporting data on post-COVID symptoms at two-years after infection were included. Methodological quality was assessed using the Newcastle-Ottawa Scale. Random-effects models were used for meta-analytical pooled prevalence of each symptom.

RESULTS

From 742 studies identified, twelve met inclusion criteria. The sample included 7912 COVID-19 survivors (50.7% female; age: 59.5, SD: 16.3). Post-COVID symptoms were assessed at a follow-up of 722.9 (SD: 51.5) days after. The overall methodological quality of studies was moderate (mean: 6/10, SD: 1.2 points). The most prevalent post-COVID symptoms two-years after SARS-CoV-2 infection were fatigue (28.0%, 95%CI 12.0-47.0), cognitive impairments (27.6%, 95%CI 12.6-45.8), and pain (8.4%, 95%CI 4.9-12.8). Psychological disturbances such as anxiety (13.4%, 95%CI 6.3-22.5) and depressive (18.0%, 95%CI 4.8-36.7) levels as well as sleep problems (20.9%, 95%CI 5.25-43.25) were also prevalent. Pooled data showed high heterogeneity (I2 ≥ 75%).

CONCLUSION

This meta-analysis shows the presence of post-COVID symptoms in 30% of patients two-years after COVID-19. Fatigue, cognitive disorders, and pain were the most prevalent post-COVID symptoms. Psychological disturbances as well as sleep problems were still present two-years after COVID-19.

Trajectory of post-COVID brain fog, memory loss, and concentration loss in previously hospitalized COVID-19 survivors: the LONG-COVID-EXP multicenter study

Objective

This study aimed to apply Sankey plots and exponential bar plots for visualizing the trajectory of post-COVID brain fog, memory loss, and concentration loss in a cohort of previously hospitalized COVID-19 survivors.

Methods

A sample of 1,266 previously hospitalized patients due to COVID-19 during the first wave of the pandemic were assessed at 8.4 (T1), 13.2 (T2), and 18.3 (T3) months after hospital discharge. They were asked about the presence of the following self-reported cognitive symptoms: brain fog (defined as self-perception of sluggish or fuzzy thinking), memory loss (defined as self-perception of unusual forgetfulness), and concentration loss (defined as self-perception of not being able to maintain attention). We asked about symptoms that individuals had not experienced previously, and they attributed them to the acute infection. Clinical and hospitalization data were collected from hospital medical records.

Results

The Sankey plots revealed that the prevalence of post-COVID brain fog was 8.37% (n = 106) at T1, 4.7% (n = 60) at T2, and 5.1% (n = 65) at T3, whereas the prevalence of post-COVID memory loss was 14.9% (n = 189) at T1, 11.4% (n = 145) at T2, and 12.12% (n = 154) at T3. Finally, the prevalence of post-COVID concentration loss decreased from 6.86% (n = 87) at T1, to 4.78% (n = 60) at T2, and to 2.63% (n = 33) at T3. The recovery exponential curves show a decreasing trend, indicating that these post-COVID cognitive symptoms recovered in the following years after discharge. The regression models did not reveal any medical record data associated with post-COVID brain fog, memory loss, or concentration loss in the long term.

Conclusion

The use of Sankey plots shows a fluctuating evolution of post-COVID brain fog, memory loss, or concentration loss during the first years after the infection. In addition, exponential bar plots revealed a decrease in the prevalence of these symptoms during the first years after hospital discharge. No risk factors were identified in this cohort.