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Letter to the Editor

Change of Safety Interval from Hyperviscosity Problem in COVID-19 Vaccine Recipient with Underlying Diabetic Problem

Sookaromdee, Pathum,; Wiwanitkit, Viroj1

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Indian Journal of Endocrinology and Metabolism: May–June 2021 - Volume 25 - Issue 3 - p 257
doi: 10.4103/ijem.ijem_308_21
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The new coronavirus disease 2019 (COVID-19) vaccine is widely used in the present day. Since COVID-19 is novel, it is necessary to have a continuous study on the effectiveness and safety of the vaccine. After the COVID-19 vaccination, an important clinical complication is a clot and thrombosis.[1]

Rheologically, there is a change of blood viscosity after the COVID-19 vaccination. According to a recent report, the blood viscosity in a normal COVID-19 vaccine recipient increases by +2.4 cp from the normal level.[2] If there is a very high increase, it might reach 5 cp,[3] which might result in vascular thrombotic complications. For any COVID-19 recipient, there will be a safety interval for which there is no hyperviscosity problem. This value is equal to the difference between hyperviscosity level minus the elevated viscosity level after vaccination. This problem might occur in a person with an underlying disease. A diabetic patient is presently examined about the risk.

In this study, the authors estimated the safety interval from high viscosity problem for a diabetic patient after receiving the COVID19 vaccine. The results of a previous publication on background blood viscosity among diabetic patients are used as primary data for modeling calculation.[4] The estimated safety intervals for diabetic patients and healthy persons are shown in Table 1.

Table 1:
Estimated safety margin for no hyperviscosity problem after COVID-19 vaccination

According to this study, there is a difference in safety interval among different groups. Diabetic patients with retinopathy form the group with the narrowest safety interval. Nevertheless, there is still a safety interval for any diabetic patient to receive the COVID-19 vaccine.

Based on the present findings, there should be close monitoring of a diabetic patient with poor diabetic control after COVID-19 vaccination.

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Conflicts of interest

There are no conflicts of interest.


Copyright: © 2021 Indian Journal of Endocrinology and Metabolism