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Published on: October 22, 2014
Elevated blood viscosity is associated with dysautonomia in long COVID symptoms
Leonardo Tamariz1,2, Isabela Milanes2, Elizabeth Bast2
1Department of Public Health Sciences, Miller School of Medicine at the University of Miami, Miami, FL, United States of America.
Insights
Long COVID patients show elevated blood viscosity, which is linked to dysautonomia but not directly to long COVID symptoms. This finding may help understand the condition
Area of Science:
- Cardiovascular Physiology
- Infectious Disease Epidemiology
- Clinical Medicine
Background:
- Long COVID is frequently associated with heightened inflammatory markers and antibody levels.
- Elevated plasma proteins can lead to increased blood viscosity, potentially impairing blood flow.
- Understanding the relationship between blood viscosity and long COVID is crucial for patient management.
Purpose of the Study:
- To investigate the association between whole blood viscosity (WBV) and long COVID outcomes.
- To determine if increased blood viscosity correlates with specific long COVID symptoms or dysautonomia.
Main Methods:
- A cross-sectional study involving 185 patients from a long COVID clinic.
- Whole blood viscosity (WBV) was estimated using validated formulas at three shear stress levels.
- WBV was compared with measures of dysautonomia (NASA lean test, COMPASS-31) and symptom burden (modified COVID-19 Yorkshire scale).
Main Results:
- No significant change in long COVID symptom burden (C19-YRSm) was observed with increasing WBV tertiles.
- The COMPASS-31 score, a measure of dysautonomia, significantly increased with higher WBV tertiles across all shear stress levels.
- Prevalence of POTS or orthostatic hypotension was higher in the highest WBV tertile (32%) compared to the lowest (23%).
Conclusions:
- Whole blood viscosity is significantly associated with dysautonomia in long COVID patients.
- Blood viscosity does not appear to be directly associated with the overall symptom burden of long COVID.
- Findings suggest a potential role for blood rheology in the pathophysiology of dysautonomia post-COVID-19.
Background:
Long COVID is associated with elevated inflammatory and antibody levels. Elevated plasma proteins can increase blood viscosity and decrease blood flow. Our aim is to evaluate if blood viscosity is associated with long COVID outcomes.
Methods:
We conducted a cross-sectional study and included a sample of patients enrolled in our long COVID clinic. We estimated whole blood viscosity (WBV) using two previously validated formulas and compared it with the NASA lean test, COMPASS-31 scale as measures of dysautonomia and the symptom burden as measured by the modified COVID-19 Yorkshire scale. We obtained WBV at three different shear stress. We divided WBV and evaluated the distribution of symptom scores using univariate and multivariate models.
Results:
We included 185 patients for this study. Our sample had a mean age of 56 ± 11 years, included 53% minorities and 32% were women. The mean C19-YRSm did not change with increasing tertile of WBV (p > 0.05) while the mean COMPASS-31 score increased with increasing tertile of WBV in all levels of shear stress. In adjusted models the beta-coefficient of the C19-YRSm was (B -0.19p = 0.90) and for COMPASS-31 was (B 7.0 p = 0.01) for 208 s-1 and for all other levels of shear stress Twenty-three percent of patients in tertile 1 had either POTS or orthostatic hypotension compared to 32% on tertile 3 (p = 0.04).
Conclusion:
Whole blood viscosity was associated with dysautonomia and not with long COVID symptoms.
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