Prevalence and assessment of risk factors among Polish adults with post-COVID-19 syndrome: a 12-month follow-up study

INTRODUCTION

Previous studies have indicated that COVID-19 symptoms may persist for up to 12 months after recovery; however, data on this phenomenon are still limited.

OBJECTIVES

The aim of this study was to assess the prevalence, the most common symptoms, and the risk factors for development of post-COVID syndrome in hospitalized and nonhospitalized patients during a 12-month follow-up after recovery from COVID-19.

PATIENTS AND METHODS

This longitudinal study was based on medical data collected at follow-up visits at 3 and 12 months post-COVID-19. Sociodemographic data, chronic conditions, and the most common clinical symptoms were assessed. A total of 643 patients were enrolled in the final analysis.

RESULTS

A majority of the study group were women (63.1%), and the median age of the entire group was 52 years (interquartile range [IQR] 43-63). After 12 months, a median of 65.7% (IQR, 62.1%-69.6%) of the patients declared the presence of at least 1 clinical symptom of post-COVID syndrome. The most common complaints were asthenia (median, 45.7% [IQR, 41.9%-49.6%]) and neurocognitive symptoms (median, 40% [IQR, 36%-40.1%]). In a multivariable analysis, female sex (odds ratio [OR] 1.49; P = 0.01) and severe COVID-19 course (OR, 3.05; P <0.001) were associated with persistence of clinical symptoms for up to 12 months after recovery.

CONCLUSIONS

After 12 months, persistent symptoms were declared by 65.7% of the patients. The most common symptoms 3 and 12 months after the infection were worse tolerance to exercise, fatigue, palpitations, and memory or concentration problems. Women are at a higher risk of experiencing persistent symptoms, and COVID-19 severity was a predictor of persistent post-COVID-19 symptoms.

Chronic Fatigue Associated with Post-COVID Syndrome versus Transient Fatigue Caused by High-Intensity Exercise: Are They Comparable in Terms of Vascular Effects?

Purpose

The pathophysiology of chronic fatigue associated with post-COVID syndrome is not well recognized. It is assumed that this condition is partly due to vascular dysfunction developed during an acute phase of infection. There is great demand for a diagnostic tool that is able to clinically assess post-COVID syndrome and monitor the rehabilitation process.

Patients and Methods

The Flow Mediated Skin Fluorescence (FMSF) technique appears uniquely suitable for the analysis of basal microcirculatory oscillations and reactive hyperemia induced by transient ischemia. The FMSF was used to measure vascular circulation in 45 patients with post-COVID syndrome. The results were compared with those for a group of 26 amateur runners before and after high-intensity exercise as well as for a control group of 32 healthy age-matched individuals.

Results

Based on the observed changes in the NOI (Normoxia Oscillatory Index) and RHR (Reactive Hyperemia Response) parameters measured with the FMSF technique, it was found that chronic fatigue associated with post-COVID syndrome is comparable with transient fatigue caused by high-intensity exercise in terms of vascular effects, which are associated with vascular stress in the macrocirculation and microcirculation. Acute and chronic fatigue symptomatology shared similarly altered changes in the NOI and RHR parameters and both can be linked to calcium homeostasis modification.

Conclusion

The NOI and RHR parameters measured with the FMSF technique can be used for non-invasive clinical assessment of post-COVID syndrome as well as for monitoring the rehabilitation process.