Modulations of circadian blood pressure rhythm in the COVID-19 risk model in individuals with arterial hypertension under Arctic watch conditions

Objective. To study the characteristics of the daily rhythm and chronostructure of blood pressure (BP) in relation to viral infection and to determine the factors influencing the risk of COVID-19 in men (M) with arterial hypertension (HTN) during rotational shift work in the Arctic. Design and methods. In the Yamburg settlement, 166 M with HTN were randomly selected from the database of physical examinations of the medical unit of gazprom dobycha Yamburg LLC. They underwent 24-hour ambulatory BP monitoring (ABPM) and echocardiography in the “pre-C OVID” period (2019 — March 2020), after which M were divided into groups with COVID-19 (n = 94) and those without (n = 72), comparable in age and northern experience. The diagnosis of COVID-19 was based on the detection of SARS-CoV-2 RNA by polymerase chain reaction method. ABPM was performed using a standard method with determination of BP chronotypes according to the classification of Cugini P. Results. According to ABPM data in the “pre-C OVID” period, men with HTN who subsequently recovered from COVID-19 had higher average daily diastolic BP, night heart rate readings, night systolic BP, night diastolic BP and night systolic BP time index; the BP chronotype was characterized by a lower frequency of 24-hour rhythms and aperiodic HTN with high-frequency rhythms in the spectrum was significantly more frequent; a significant increase in left ventricular myocardial mass and left ventricular myocardial mass index was found. According to the logistic regression data, the presence of an aperiodic chronotype of HTN in M increased the risk of COVID-19 by 3 times (95 % confidence interval (CI): 1,410– 6,035, p = 0,004); an increase in left ventricular myocardial mass index by 1 g/m2 — by 1,02 times (95 % CI: 1,001–1,033, p = 0,039). The specificity of the model was 81 %, sensitivity 77,2 %. The area under the curve was 0,888 (0,837–0,939, p < 0,0001). Conclusions. In conditions of desynchronizing factors of the Arctic watch in M with HTN, the replacement of the daily BP rhythm by predominant high-frequency periods is associated with the risk of COVID-19 infection.