The phenomenon of glycated hemoglobin in patients with a new coronavirus infection (COVID-19) with type 2 diabetes mellitus

Bogdan А. Sklyarov, Alena D. Samoilova, Bogdan V. Pavlov, Anastasia V. Levina, Irina S. Sinelnikova, Susanna М. Vardanyan, Viktor А. Papin. The phenomenon of glycated hemoglobin in patients with a new coronavirus infection (COVID-19) with type 2 diabetes mellitus. Cardiometry; Issue No. 26; February 2023; p. 139-143; DOI: 10.18137/cardiometry.2023.26.139143; Available from: phenomenon-glycated-hemoglobin

The new coronavirus infection (COVID-19) has many clinical manifestations and also causes severe respiratory distress syndromes that lead to metabolic disorders. An identification of factors, which influence the severity of the patient’s condition, is important. Patients with diabetes account for approximately one third of the confirmed cases of COVID-19 [1]. Glycosylated hemoglobin (hereinafter referred to as HbA1c) gives a better idea on the patient’s glycemic control [2]. HbA1c is a product of non-enzymatic hemoglobin glycation, reflecting an averaged plasma glucose level through the previous 2-3 months [3], and it is at the same time both a marker for diagnostics and a target for treatment [4, 5].

In the course of the study, we took clinical indicators of 15 patients aged 45 to 65 years, who infected with the coronavirus and who suffered from type 2 diabetes mellitus with elevated HbA1c, who were treated at a hospital for the COVID-19patients. All patients have previously given their written consent on medical intervention and processing of their personal data. During the observation and measurement of patients’ parameters, we found that on the 7th day, when oxygen therapy was added, HbA1c began to behave chaotically, after which an increase in the parameter was detected with its maximum recorded to be 15.1%. Further, a phenomenon was recorded, namely from 7 to 12 days, when an increase in the HbA1c value was found to be not typical for the above indicator, since we know that it shows the glucose level as a result from the last 3 months. From day 13, HbA1c dropped sharply, and until day 21, we observed a decrease in the HbA1c value to 5.1%

Further, we have noticed that a sharp drop in the HbA1c value is fatal. If the HbA1c level does not fall below 6.5%, then the outcome is more favorable. The optimal performance for this phenomenon or a favorable outcome is recorded at a glucose level not higher than 12.0 -13.5 mmol / l, while the HbA1c value should not exceed 10.0%, and its sharp drop should not be below 6.5%.

In the infected patients, there was severe intoxication, lack of appetite (diabetes associated with hy-poinsulinemia develops against the background of starvation, which exacerbates and increases glycated hemoglobin), body weight loss, and lack of basal insulin. As a result of observation, 10 patients, who had high levels of blood glucose and HbA1c, died at the hospital, and 5 individuals with more optimal indi- cators were discharged from the hospital with an improvement in their general health state.

Higher levels of HbA1c in the patients with diabetes directly affect the severity of the condition in the COVID-19patients that is a factor responsible for an aggravation of the condition of these patients and that may lead to their death. This phenomenon is explained by the fact that coronavirus infection triggers mechanisms responsible for increasing blood glucose levels, in this case, it retains an excess of glucose in the organism. In addition, hyperglycemia causes structural changes in the lung tissue, including collapse of some parts of the lungs and increased permeability of blood vessels [6]. The main complication of the coronavirus infection in hospitalized patients is pneumonia [7].

Table 1

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Dav Dav Dav Day Dav Dav Day Day Day Dav Dav Dav Dav Dav Dav Dav Dav Dav Dav Day Day

1    2    3   4    5    6   7    8    9   10 11 12 13 14 15 16 17 18   19 20 21

--Patient 1 — Patient 2 ■

- - Patient 6 — Patient 7 -^—

— Patient 11 Patient 12

Patient 3 -

Patient 8 —

Patient 13^—

Patient 4

Patient 9

Patient 14

— Patient 5

— Patient 10

Patient 15

Figure 1. The phenomenon of glycated hemoglobin in coronavirus infection COVID-19 during oxygen therapy 140 | Cardiometry | Issue 26. February 2023