Category: Overlapping Illnesses

How methodological pitfalls have created widespread misunderstanding about long COVID

Key messages:

  • The existing epidemiological research on long COVID has suffered from overly broad case definitions and a striking absence of control groups, which have led to distortion of risk.

  • The unintended consequences of this may include, but are not limited to, increased societal anxiety and healthcare spending, a failure to diagnose other treatable conditions misdiagnosed as long COVID and diversion of funds and attention from those who truly suffer from chronic conditions secondary to COVID-19.

  • Future research should include properly matched control groups, sufficient follow-up time after infection and internationally-established diagnostic or inclusion and exclusion criteria.

Source: Høeg TB, Ladhani S, Prasad V. How methodological pitfalls have created widespread misunderstanding about long COVID. BMJ Evid Based Med. 2023 Sep 25:bmjebm-2023-112338. doi: 10.1136/bmjebm-2023-112338. Epub ahead of print. PMID: 37748921. https://ebm.bmj.com/content/early/2023/08/10/bmjebm-2023-112338 (Full text)

Long-Term cognitive dysfunction after the COVID-19 pandemic: a narrative review

Abstract:

Introduction: SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has brought a conglomerate of novel chronic disabling conditions described as ‘Long COVID/Post-COVID-19 Syndrome’. Recent evidence suggests that the multifaceted nature of this syndrome results in both pulmonary and extrapulmonary sequelae, chronic dyspnoea, persistent fatigue, and cognitive dysfunction being the most common, debilitating symptoms. Several mechanisms engender or exacerbate cognitive impairment, including central nervous system (CNS) and extra-CNS causes, although the exact mechanism remains unclear. Both hospitalized and non-hospitalized patients may suffer varying degrees of cognitive impairment, ranging from fatigue and brain fog to prolonged deficits in memory and attention, detrimental to the quality-of-life years post-recovery. The aim of this review is to understand the underlying mechanisms, associations, and attempts for prevention with early intervention of long-term cognitive impairment post-COVID-19.

Methodology: A systematic search was conducted through multiple databases such as Medline, National Library of Medicine, Ovid, Scopus database to retrieve all the articles on the long term sequalae of cognitive dysfunction after Sars-Cov2 infection. The inclusion criteria included all articles pertinent to this specific topic and exclusion criteria subtracted studies pertaining to other aetiologies of cognitive dysfunction. This search was carefully screened for duplicates and the relevant information was extracted and analysed.

Results/discussion: To date, the exact pathogenesis, and underlying mechanisms behind cognitive dysfunction in COVID-19, remain unclear, hindering the development of adequate management strategies. However, the proposed mechanisms suggested by various studies include direct damage to the blood-brain barrier, systemic inflammation, prolonged hypoxia, and extended intensive care admissions. However, no clear-cut guidelines for management are apparent.

Conclusion: This review of the COVID-19 pandemic has elucidated a new global challenge which is affecting individuals’ quality of life by inducing long-term impaired cognitive function. We have found that comprehensive evaluations and interventions are crucial to address the cognitive sequelae in all COVID-19 patients, especially in patients with pre-existing cognitive impairment. Nevertheless, the authors recommend further research for the development of relevant, timely neurocognitive assessments and treatment plans.

Source: Shariff, Sanobar; Uwishema, Olivier; Mizero, Jocelyn; Devi Thambi, Vimala; Nazir, Abubakar; Mahmoud, Ashraf; Kaushik, Ikshwaki; Khayat, Saadeddine; Yusif Maigoro, Abdulkadir; Awde, Sara; Al Maaz, Zeina; Alwan, Iktimal; Hijazi, Mahdi; Wellington, Jack MSc (LSHTM) FGMS; Soojin, Lee. Long-Term cognitive dysfunction after the COVID-19 pandemic: a narrative review. Annals of Medicine & Surgery ():10.1097/MS9.0000000000001265, September 8, 2023. | DOI: 10.1097/MS9.0000000000001265 https://journals.lww.com/annals-of-medicine-and-surgery/abstract/9900/long_term_cognitive_dysfunction_after_the_covid_19.1011.aspx

Prevalence of musculoskeletal pain as a long-covid symptom after hospitalisation in covid-19 survivors

Abstract:

Background and aims: Up to 60% of COVID-19 survivors develop long-COVID symptomatology with 90 different manifestations. The aim of this large cohort study was to study the prevalence of persistent musculoskeletal pain as a long-COVID symptom in COVID-19 survivors.
Methods: This cross-sectional exploratory study was based on responses to pain-related questionnaires from a national survey including data from 1) 4.833 previously hospitalised patients with a confirmed SARS-CoV-2 infection and from 2) a population of 132.427 non-hospitalised SARS-CoV-2 infected persons. Time from confirmed infection to response was 8-30 months. The questionnaire was designed to focus specifically on the type of post-COVID persistent pain, pain intensities, and quality of life.
Results: Data from 1.000 randomly selected previously hospitalised (51.2% males; 60.4±15.2 years; 85.6±18.5 kg) and 1.000 randomly selected non-hospitalised COVID-19 survivors (43.5% males; 50.4±15.9 years; 79.2±16.6 kg) were included. Long-COVID pain symptoms were more prevalent within the hospital group (38.8% vs. 12.7%, p<0.001). When analysing specifically for de novo musculoskeletal pain, the prevalence was likewise highest in the hospital group (20% vs. 4.2%, p<0.001). A higher proportion (p<0.001) of previously hospitalised survivors (20%) reported presence of widespread pain when compared with non-hospitalised patients (4.2%). Long-COVID pain intensities were not different between groups (p<0.329).
Conclusions: This study showed that long-COVID musculoskeletal pain was more prevalent in the hospital group compared to a non-hospitalised group. The high prevalence of long-COVID musculoskeletal and widespread pain symptoms following SARS-CoV-2 infection highlights the need of attention to this new group of pain patients.
Source: Ebbesen, B. D., Giordano, R., Varol, U., Fernández-de-Las-Peñas, C., Rasmussen, B. S., Nielsen, H., Schiøttz-Christensen, B., Lykke Petersen, P., Castaldo, M., & Arendt-Nielsen, L. (2023). Prevalence of musculoskeletal pain as a long-covid symptom after hospitalisation in covid-19 survivors. Abstract from 13th Congress of the European Pain Federation EFIC, Budapest, Hungary. https://vbn.aau.dk/en/publications/prevalence-of-musculoskeletal-pain-as-a-long-covid-symptom-after-

Autonomic dysregulation in long-term patients suffering from Post-COVID-19 Syndrome assessed by heart rate variability

Abstract:

Post-COVID-19 Syndrome (PCS) is a condition with multiple symptoms partly related to dysregulation of the autonomic nerve system. Assessment of heart rate variability (HRV) using 24 h Holter-ECG may serve as a surrogate to characterize cardiac autonomic activity. A prospective study including 103 PCS patients (time after infection = 252 days, age = 49.0 ± 11.3 years, 45.7% women) was performed and patients underwent detailed clinical screening, cardiopulmonary exercise testing, and 24 h Holter monitoring.

Data of PCS patients was compared to 103 CAD patients and a healthy control group (n = 90). After correction for age and sex, frequency-related variables differed in PCS patients compared to controls including LF/HFpower, LF/HFnu, and LF/HF ratio (24 h; p ≤ 0.001). By contrast, these variables were largely comparable between PCS and CAD patients, while sympathetic activation was highest in PCS patients during the 24 h period.

Overall, PCS patients showed disturbed diurnal adjustment of HRV, with impaired parasympathetic activity at night. Patients hospitalized during acute infection showed an even more pronounced overactivation of sympathetic activity compared to patients who underwent ambulant care.

Our data demonstrate persistent HRV alterations in PCS patients with long-term symptom duration, suggesting a sustained impairment of sympathovagal balance. Moreover, sympathetic overstimulation and diminished parasympathetic response in long-term PCS patients are comparable to findings in CAD patients. Whether HRV variables have a prognostic value in PCS and/or might serve as biomarkers indicating a successful interventional approach warrants further longitudinal studies.

Source: Mooren FC, Böckelmann I, Waranski M, Kotewitsch M, Teschler M, Schäfer H, Schmitz B. Autonomic dysregulation in long-term patients suffering from Post-COVID-19 Syndrome assessed by heart rate variability. Sci Rep. 2023 Sep 22;13(1):15814. doi: 10.1038/s41598-023-42615-y. PMID: 37739977; PMCID: PMC10516975. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10516975/ (Full text)

The importance of patient-partnered research in addressing long COVID: Takeaways for biomedical research study design from the RECOVER Initiative’s Mechanistic Pathways taskforce

Abstract:

The NIH-funded RECOVER study is collecting clinical data on patients who experience a SARS-CoV-2 infection. As patient representatives of the RECOVER Initiative’s Mechanistic Pathways task force, we offer our perspectives on patient motivations for partnering with researchers to obtain results from mechanistic studies. We emphasize the challenges of balancing urgency with scientific rigor. We recognize the importance of such partnerships in addressing post-acute sequelae of SARS-CoV-2 infection (PASC), which includes ‘long COVID,’ through contrasting objective and subjective narratives.

Long COVID’s prevalence served as a call to action for patients like us to become actively involved in efforts to understand our condition. Patient-centered and patient-partnered research informs the balance between urgency and robust mechanistic research. Results from collaborating on protocol design, diverse patient inclusion, and awareness of community concerns establish a new precedent in biomedical research study design. With a public health matter as pressing as the long-term complications that can emerge after SARS-CoV-2 infection, considerate and equitable stakeholder involvement is essential to guiding seminal research. Discussions in the RECOVER Mechanistic Pathways task force gave rise to this commentary as well as other review articles on the current scientific understanding of PASC mechanisms.

Source: Kim C, Chen B, Mohandas S, Rehman J, Sherif ZA, Coombs K; RECOVER Mechanistic Pathways Task Force; RECOVER Initiative. The importance of patient-partnered research in addressing long COVID: Takeaways for biomedical research study design from the RECOVER Initiative’s Mechanistic Pathways taskforce. Elife. 2023 Sep 22;12:e86043. doi: 10.7554/eLife.86043. PMID: 37737716; PMCID: PMC10516599. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10516599/ (Full text)

Effects of six-month creatine supplementation on patient- and clinician-reported outcomes, and tissue creatine levels in patients with post-COVID-19 fatigue syndrome

Abstract:

Dietary creatine has been recently put forward as a possible intervention strategy to reduce post-COVID-19 fatigue syndrome yet no clinical study so far evaluated its efficacy and safety for this perplexing condition. In this parallel-group, randomized placebo-controlled double-blind trial, we analyzed the effects of 6-month creatine supplementation (4 g of creatine monohydrate per day) on various patient- and clinician-reported outcomes, and tissue creatine levels in 12 patients with post-COVID-19 fatigue syndrome.

Creatine intake induced a significant increase in tissue creatine levels in vastus medialis muscle and right parietal white matter compared to the baseline values at both 3-month and 6-month follow-ups (p < .05). Two-way analysis of variance with repeated measures revealed a significant difference (treatment vs. time interaction) between interventions in tissue creatine levels (p < .05), with the creatine group was superior to placebo to augment creatine levels at vastus medialis muscle, left frontal white matter, and right parietal white matter.

Creatine supplementation induced a significant reduction in general fatigue after 3 months of intake compared to baseline values (p = .04), and significantly improved scores for several post-COVID-19 fatigue syndrome-related symptoms (e.g., ageusia, breathing difficulties, body aches, headache, and difficulties concentrating) at 6-month follow-up (p < .05). Taking creatine for 6 months appears to improve tissue bioenergetics and attenuate clinical features of post-COVID-19 fatigue syndrome; additional studies are warranted to confirm our findings in various post-COVID-19 cohorts.

Source: Slankamenac, J., Ranisavljev, M., Todorovic, N., Ostojic, J., Stajer, V., & Ostojic, S. M. (2023). Effects of six-month creatine supplementation on patient- and clinician-reported outcomes, and tissue creatine levels in patients with post-COVID-19 fatigue syndrome. Food Science & Nutrition, 00, 1–7. https://doi.org/10.1002/fsn3.3597 (Full text)

Clinical Rationale for Dietary Lutein Supplementation in Post COVID-19 and mRNA Vaccine Injury Syndromes

Abstract:

Lutein, a plant-derived xanthophyl-carotenoid, is an exceptional antioxidant and anti-inflammatory constituent found in food. Elevated concentrations of lutein found in human blood and plasma, due to high dietary intake, are beneficial against eye disease and improve cardiometabolic health.

Lutein plays an important protective role against the development of neurological disorders, including Alzheimer’s disease (AD), multiple sclerosis (MS) and Parkinson’s disease (PD). It has also been shown to be beneficial for liver, kidney and respiratory health. Lutein, acting as a very strong antioxidant, can alleviate oxidative stress and downgrade reactive oxygen species (ROS). Oxidative stress is one of the key pathogenic mechanisms in post-COVID and mRNA vaccine injury syndromes.

Recent in silico studies suggest that lutein and other naturally derived antioxidants, by docking at the site where the SARS-CoV-2 spike protein (SP) binds to the angiotensin enzyme type 2 (ACE2) receptor, may neutralize the SP-ACE2 interactions. Lutein can be added to a detoxification regimen to aid in clearing Spike protein and relieving symptoms.

In agreement with Hippocrates’ dictum to “Let food be thy medicine,” this review establishes dietary lutein as a valuable therapy in the treatment of post-COVID syndrome, mRNA vaccine injury syndromes, and a wide range of other chronic illnesses.

Source: Kyriakopoulos, A.M.; Nigh, G.; McCullough, P.A.; Seneff, S. Clinical Rationale for Dietary Lutein Supplementation in Post COVID-19 and mRNA Vaccine Injury Syndromes. Preprints 2023, 2023091385. https://doi.org/10.20944/preprints202309.1385.v1 https://www.preprints.org/manuscript/202309.1385/v1 https://www.preprints.org/manuscript/202309.1385/v1 (Full text available as PDF file)

Immune Adsorption for the Treatment of Fatigue-Dominant Long-/Post-COVID Syndrome

Introduction:

Following an infection with SARS-CoV-2, a relevant proportion of patients suffer from fatigue-dominant long-/post-COVID syndrome. In 57% of patients with long-/post-COVID syndrome, who were treated in a university hospital, increased levels of autoantibodies (AABs) to G-protein-coupled neurotransmitter receptors (including ß-adrenergic and muscarinic) were detected ().

Reduction of ß-adrenergic AABs by immunoadsorption therapy was associated with clinical improvement in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) (). Increasingly, reports of individual cases of successful treatment of long/post-COVID syndrome with the help of apheresis techniques have been widely disseminated via social media. By contrast, cases or studies with negative outcomes are much less likely to receive proper attention. Given the overall lack of data to date, medical societies are calling for a broader scientific basis, to which we would like to contribute with this case series.

Source: Ruhe J, Giszas B, Schlosser M, Reuken PA, Wolf G, Stallmach A. Immune Adsorption for the Treatment of Fatigue-Dominant Long-/Post-COVID Syndrome: A Series of Cases With Standardized Individual Experimental Therapy. Dtsch Arztebl Int. 2023 Jul;120(29-30):499–500. doi: 10.3238/arztebl.m2023.0073. Epub 2023 Jul 24. PMCID: PMC10511006. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10511006/ (Full text)

Incidence of immune-mediated inflammatory diseases following COVID-19: a matched cohort study in UK primary care

Abstract:

Background: Some patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) go on to experience post-COVID-19 condition or long COVID. Preliminary findings have given rise to the theory that long COVID may be due in part to a deranged immune response. In this study, we assess whether there is an association between SARS-CoV-2 infection and the incidence of immune-mediated inflammatory diseases (IMIDs).

Methods: Matched cohort study using primary care electronic health record data from the Clinical Practice Research Datalink Aurum database. The exposed cohort included 458,147 adults aged 18 years and older with a confirmed SARS-CoV-2 infection and no prior diagnosis of IMIDs. They were matched on age, sex, and general practice to 1,818,929 adults with no diagnosis of confirmed or suspected SARS-CoV-2 infection. The primary outcome was a composite of any of the following IMIDs: autoimmune thyroiditis, coeliac disease, inflammatory bowel disease (IBD), myasthenia gravis, pernicious anaemia, psoriasis, rheumatoid arthritis (RA), Sjogren’s syndrome, systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1DM), and vitiligo. The secondary outcomes were each of these conditions separately. Cox proportional hazard models were used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for the primary and secondary outcomes, adjusting for age, sex, ethnic group, smoking status, body mass index, relevant infections, and medications.

Results: Six hundred and nighty six (0.15%) and 2230 (0.12%) patients in the exposed and unexposed cohort developed an IMID during the follow-up period over 0.29 person-years, giving a crude incidence rate of 4.59 and 3.65 per 1000 person-years, respectively. Patients in the exposed cohort had a 22% increased risk of developing an IMID, compared to the unexposed cohort (aHR 1.22, 95% CI 1.12 to 1.33). The incidence of three IMIDs was significantly associated with SARS-CoV-2 infection. These were T1DM (aHR 1.56, 1.09 to 2.23), IBD (aHR 1.36, 1.18 to 1.56), and psoriasis (1.23, 1.05 to 1.42).

Conclusions: SARS-CoV-2 was associated with an increased incidence of IMIDs including T1DM, IBD and psoriasis. However, these findings could be potentially due to ascertainment bias. Further research is needed to replicate these findings in other populations and to measure autoantibody profiles in cohorts of individuals with COVID-19.

Source: Syed U, Subramanian A, Wraith DC, Lord JM, McGee K, Ghokale K, Nirantharakumar K, Haroon S. Incidence of immune-mediated inflammatory diseases following COVID-19: a matched cohort study in UK primary care. BMC Med. 2023 Sep 21;21(1):363. doi: 10.1186/s12916-023-03049-5. PMID: 37735654; PMCID: PMC10512476. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10512476/ (Full text)

Characterization of long COVID temporal sub-phenotypes by distributed representation learning from electronic health record data: a cohort study

Abstract:

Background: Characterizing Post-Acute Sequelae of COVID (SARS-CoV-2 Infection), or PASC has been challenging due to the multitude of sub-phenotypes, temporal attributes, and definitions. Scalable characterization of PASC sub-phenotypes can enhance screening capacities, disease management, and treatment planning.

Methods: We conducted a retrospective multi-centre observational cohort study, leveraging longitudinal electronic health record (EHR) data of 30,422 patients from three healthcare systems in the Consortium for the Clinical Characterization of COVID-19 by EHR (4CE). From the total cohort, we applied a deductive approach on 12,424 individuals with follow-up data and developed a distributed representation learning process for providing augmented definitions for PASC sub-phenotypes.

Findings: Our framework characterized seven PASC sub-phenotypes. We estimated that on average 15.7% of the hospitalized COVID-19 patients were likely to suffer from at least one PASC symptom and almost 5.98%, on average, had multiple symptoms. Joint pain and dyspnea had the highest prevalence, with an average prevalence of 5.45% and 4.53%, respectively.

Interpretation: We provided a scalable framework to every participating healthcare system for estimating PASC sub-phenotypes prevalence and temporal attributes, thus developing a unified model that characterizes augmented sub-phenotypes across the different systems.

Source: Dagliati A, Strasser ZH, Hossein Abad ZS, Klann JG, Wagholikar KB, Mesa R, Visweswaran S, Morris M, Luo Y, Henderson DW, Samayamuthu MJ, Tan BWQ, Verdy G, Omenn GS, Xia Z, Bellazzi R; Consortium for Clinical Characterization of COVID-19 by EHR (4CE),; Murphy SN, Holmes JH, Estiri H; Consortium for Clinical Characterization of COVID-19 by EHR (4CE). Characterization of long COVID temporal sub-phenotypes by distributed representation learning from electronic health record data: a cohort study. EClinicalMedicine. 2023 Sep 14;64:102210. doi: 10.1016/j.eclinm.2023.102210. PMID: 37745021; PMCID: PMC10511779. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10511779/ (Full text)