Author contribution: Rakhmanov RS — study design and concept, article authoring; Bogomolova ES — editing, approval of the final version of the article; Narutdinov DA — primary material collection; Razgulin SA — literature analysis; Potekhina NN — participation in statistical processing of the material.

Compliance with the ethical standards: the study was approved by the Ethics Committee of the Privolzhsky Research Medical University of the Ministry of Health of the Russian Federation (Minutes #4 of March 14, 2022); all study participants signed a voluntary informed consent form.