Cognitive, Psychological, and Physical Functioning in Long-COVID Patients With Different Levels of Fatigue.

Post COVID-19 usually occurs 3 months from the onset of COVID-19 with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis. Patients report a range of disabling symptoms such as fatigue, shortness of breath, cognitive impairment, memory loss and mental health and employment issues. This clinical heterogeneity complicates the identification of the appropriate needs and care.

The aim of this cross-sectional study is to identify subgroups (clusters) of post COVID patients based on clinical symptoms, demographic characteristics, levels of fatigue and physical, cognitive and psychological functioning of the individuals.

Study Overview

• Status: Completed
• Conditions: Post-Acute COVID-19 Syndrome

• Study Type: Observational
• Enrollment (Actual): 69

Contacts and Locations

Study Locations

• Belgium
  • Diepenbeek, Belgium, 3590
    • Hasselt University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Participants that match the criteria of the recently published definition of the post-COVID-19 condition will be considered eligible to participate in the study.[8] Post-COVID-19 has been defined as a condition that occurs in individuals with a history of confirmed SARS-CoV-2 infection, and that occurs usually within three months from the onset of COVID-19 with symptoms that last for at least two months and cannot be explained by an alternative diagnosis. Consequently, participants that either have or have not been hospitalized will both be allowed to participate in this study. COVID infection will be self-reported by the participant. Participants will be encouraged to show any test certificate but they are not obligated to do so.

Description

Inclusion Criteria:

The participant must report current persisting symptoms (such as brain fog, anxiety, shortness of breath, headaches but also others) and indicate on the Post COVID-19 Functional Status Scale that these have an impact on everyday functioning (grade 2, 3, and 4). These symptoms need to be present for more than two months.

Further inclusion criteria are:

• Fatigue Severity Scale (FSS) score > 4
• Aged over 18 years old
• Willing to sign the digital informed consent
• Dutch speaking and Dutch understanding
• Be tested positive for COVID-19, i.e. by reverse transcription polymerase chain reaction (RT-PCR), computed tomography (CT) of the lungs, or symptom-based diagnosis by the general practitioner.

Exclusion Criteria:

• Pregnant women
• Pacemaker, defibrillator
• Brain or nerve disorders
• Epilepsy
• A copper spiral or recent bone fracture

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physical evaluation	Hand grip strength (Jamar hand dynamometer) & Six Minute Walk Test (6MWT)	Day 1
Fatigue severity	Fatigue severity scale (FSS)	Day 1
Cognitive evaluation	Multi-modal Evaluation of Sensory Sensitivity (MESSY); Montreal Cognitive Assessment (MoCA)	Day 1
Psychological evaluation	Anxiety and depression Scale (HADS); MINI-S, MINI International Neuropsychiatric Interview - Simplified (Overbeek & Schruers 2019)	Day 1

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of clusters	The main outcome of the study is identification of the best-fitting number of clusters and the reliability of clustering. To check for differences in characteristics between the clusters, we will use an analysis of variance for normally distributed continuous variables and the nonparametric Kruskal-Wallis test for nonnormally variances (R package "FSA").	Day 1

Collaborators and Investigators

• Sponsor: Hasselt University

Study record dates

Study Major Dates

• Study Start (Actual): May 5, 2023
• Primary Completion (Actual): June 1, 2024
• Study Completion (Actual): June 1, 2024

Study Registration Dates

• First Submitted: February 8, 2023
• First Submitted That Met QC Criteria: March 6, 2023
• First Posted (Actual): March 7, 2023

Study Record Updates

• Last Update Posted (Actual): February 12, 2026
• Last Update Submitted That Met QC Criteria: February 10, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Post-Infectious Disorders; COVID-19; Pathologic Processes; Chronic Disease; Disease Attributes; Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; Pathological Conditions, Signs and Symptoms; Post-Acute COVID-19 Syndrome
• Other Study ID Numbers: CME2022/021 S66200

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No