Vagus nerve dysfunction in the post-COVID-19 condition: a pilot cross-sectional study.

OBJECTIVES: The post-COVID-19 condition (PCC) is a disabling syndrome affecting at least 5%-10% of subjects who survive COVID-19. SARS-CoV-2 mediated vagus nerve dysfunction could explain some PCC symptoms, such as dysphonia, dysphagia, dyspnea, dizziness, tachycardia, orthostatic hypotension, gastrointestinal disturbances, or neurocognitive complaints. METHODS: We performed a cross-sectional pilot study in subjects with PCC with symptoms suggesting vagus nerve dysfunction (n = 30) and compared them with subjects fully recovered from acute COVID-19 (n = 14) and with individuals never infected (n = 16). We evaluated the structure and function of the vagus nerve and respiratory muscles. RESULTS: Participants were mostly women (24 of 30, 80%), and the median age was 44 years (interquartile range [IQR] 35-51 years). Their most prevalent symptoms were cognitive dysfunction 25 of 30 (83%), dyspnea 24 of 30 (80%), and tachycardia 24 of 30 (80%). Compared with COVID-19-recovered and uninfected controls, respectively, subjects with PCC were more likely to show thickening and hyperechogenic vagus nerve in neck ultrasounds (cross-sectional area [CSA] [mean ± standard deviation]: 2.4 ± 0.97mm2 vs. 2 ± 0.52mm2 vs. 1.9 ± 0.73 mm2; p 0.08), reduced esophageal-gastric-intestinal peristalsis (34% vs. 0% vs. 21%; p 0.02), gastroesophageal reflux (34% vs. 19% vs. 7%; p 0.13), and hiatal hernia (25% vs. 0% vs. 7%; p 0.05). Subjects with PCC showed flattening hemidiaphragms (47% vs. 6% vs. 14%; p 0.007), and reductions in maximum inspiratory pressure (62% vs. 6% vs. 17%; p ≤ 0.001), indicating respiratory muscle weakness. The latter findings suggest additional involvement of the phrenic nerve. DISCUSSION: Vagus and phrenic nerve dysfunction contribute to the complex and multifactorial pathophysiology of PCC.

Determinants of the onset and prognosis of the post-COVID-19 condition: a 2-year prospective observational cohort study.

Background: At least 5-10% of subjects surviving COVID-19 develop the post-COVID-19 condition (PCC) or "Long COVID". The clinical presentation of PCC is heterogeneous, its pathogenesis is being deciphered, and objective, validated biomarkers are lacking. It is unknown if PCC is a single entity or a heterogeneous syndrome with overlapping pathophysiological basis. The large US RECOVER study identified four clusters of subjects with PCC according to their presenting symptoms. However, the long-term clinical implications of PCC remain unknown. Methods: We conducted a 2-year prospective cohort study of subjects surviving COVID-19, including individuals fulfilling the WHO PCC definition and subjects with full clinical recovery. We systematically collected post-COVID-19 symptoms using prespecified questionnaires and performed additional diagnostic imaging tests when needed. Factors associated with PCC were identified and modelled using logistic regression. Unsupervised clustering analysis was used to group subjects with PCC according to their presenting symptoms. Factors associated with PCC recovery were modelled using a direct acyclic graph approach. Findings: The study included 548 individuals, 341 with PCC, followed for a median of 23 months (IQR 16.5-23.5), and 207 subjects fully recovered. In the model with the best fit, subjects who were male and had tertiary studies were less likely to develop PCC, whereas a history of headache, or presence of tachycardia, fatigue, neurocognitive and neurosensitive complaints and dyspnea at COVID-19 diagnosis predicted the development of PCC. The cluster analysis revealed the presence of three symptom clusters with an additive number of symptoms. Only 26 subjects (7.6%) recovered from PCC during follow-up; almost all of them (n = 24) belonged to the less symptomatic cluster A, dominated mainly by fatigue. Recovery from PCC was more likely in subjects who were male, required ICU admission, or had cardiovascular comorbidities, hyporexia and/or smell/taste alterations during acute COVID-19. Subjects presenting with muscle pain, impaired attention, dyspnea, or tachycardia, conversely, were less likely to recover from PCC. Interpretation: Preexisting medical and socioeconomic factors, as well as acute COVID-19 symptoms, are associated with the development of and recovery from the PCC. Recovery is extremely rare during the first 2 years, posing a major challenge to healthcare systems. Funding: Fundació Lluita contra les Infeccions.

Social, Academic, and Health Status Impact of Long COVID on Children and Young People: An Observational, Descriptive, and Longitudinal Cohort Study.

There is a lack of evidence of the health impacts due to long COVID among children and young people (CYP). The objective of this study is to determine the main clinical characteristics of long COVID in CYP and to investigate the academic, social, and health status impacts of long COVID in this population. An observational, descriptive, and longitudinal study on CYP who presented COVID-19 symptoms for more than twelve weeks after SARS-CoV-2 infection was performed between December 2020 and May 2021. Fifty CYP were included, with a median age of 14.1 years, 33 (66%) were female, and 17 (34%) had a relative diagnosed with long COVID. Since the initial infection and up to the first visit, CYP had persisting symptoms for a median of 4.1 months, and for 18 (36%) CYP these symptoms persisted for more than 6 months. Fatigue (100%), neurocognitive disorders (74%), muscular weakness (74%), and headache (72%) were the most reported symptoms. A total of 9 (18%) CYP could not attend school, 17 (34%) had a reduced schedule, 33 (66%) showed a decreased school performance, and 68% had stopped extracurricular activities. This preliminary study shows the impact that long COVID has on the health, academic, and social life of CYP.

Supervised versus non-supervised exercise in patients with recent myocardial infarction: A propensity analysis.

BACKGROUND: The influence of supervised versus non-supervised exercise training on outcome in patients with a recent myocardial infarction (MI) is controversial. DESIGN: Longitudinal observational study. METHODS: FRENA is an ongoing registry of stable outpatients with symptomatic coronary, cerebrovascular or peripheral artery disease. We compared the rate of subsequent ischaemic events (MI, ischaemic stroke or lower limb amputation) and the mortality rate in patients with recent MI, according to the use of supervised versus non-supervised exercise training. The influence of physical activity on outcomes was estimated by using propensity score method in multivariate analysis. RESULTS: As of February 2014, 1124 outpatients with recent MI were recruited, of whom 593 (53%) participated in a supervised exercise training programme. Over a mean follow-up of 15 months, 25 patients (3.3%) developed 26 subsequent ischaemic events - 24 MI, one stroke, one lower-limb amputation - and 12 (1.6%) died. The mortality rate (0.15 vs. 2.89 deaths per 100 patient-years; rate ratio = 0.05; 95% confidence interval, 0.01-0.39) was significantly lower in supervised exercise than in non-supervised exercise patients. On propensity score analysis, the rate of the composite outcome was significantly lower in supervised exercise patients (1.80 vs. 6.51 events per 100 patient-years; rate ratio = 0.28; 95% confidence interval, 0.12-0.64). CONCLUSIONS: The use of supervised exercise training in patients with recent MI was associated with a significant decrease in the composite outcome of subsequent ischaemic events and death.

Cardiac rehabilitation and outcome in stable outpatients with recent myocardial infarction.

OBJECTIVE: To compare the mortality rate and the rate of subsequent ischemic events (myocardial infarction [MI], ischemic stroke, or limb amputation) in patients with recent MI according to the use of cardiac rehabilitation or no rehabilitation. DESIGN: Longitudinal observational study. SETTING: Ongoing registry of outpatients. PARTICIPANTS: Patients (N=1043) with recent acute MI were recruited; of these, 521 (50%) participated in cardiac rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subsequent ischemic events and mortality rates were registered. RESULTS: Over a mean follow-up of 18 months, 50 patients (4.8%) died and 49 (4.7%) developed 52 subsequent ischemic events (MI: n=43, ischemic stroke: n=6, limb amputation: n=3). Both the mortality rate (.16 vs 5.57 deaths per 100 patient-years; rate ratio=.03; 95% confidence interval [CI], 0.0-0.1]) and the rate of subsequent ischemic events (1.65 vs 4.54 events per 100 patient-years; rate ratio=0.4; 95% CI, 0.2-0.7) were significantly lower in cardiac rehabilitation participants than in nonparticipants. Multivariate analysis confirmed that patients in cardiac rehabilitation had a significantly lower risk of death (hazard ratio=.08; 95% CI, .01-.63; P=.016) and a nonsignificant lower risk of subsequent ischemic events (hazard ratio=.65; 95% CI, .30-1.42). CONCLUSIONS: The use of cardiac rehabilitation in patients with recent MI was independently associated with a significant decrease in the mortality rate and a nonsignificant decrease in the rate of subsequent ischemic events.