Chronodiagnostics and chronotherapy - frontiers for personalized clinical medicine

Ignoring the timing in the diagnosis and treatment of diseases becomes an anachronism. Expression of majority of omnipresent genes follow circadian rhythm. Consequently, the existence of a pronounced 24-hour variability of clinically most valuable parameters means just one thing - ignorance or misunderstanding circadian variability will inevitably lead to incorrect interpretation of the results and a high frequency of diagnostic errors. In addition, the variability of physiological functions changes with the development and progression of pathology, losing its order. Amplitude-phase parameters of the circadian rhythm are of special interest for the development of chronodiagnostic methods. On the other hand, the time of prescribing a drug or other therapeutic or preventive action can critically affect its result. Decisive conditions for the breakthrough and translation of fundamental knowledge of chronobiology into practical healthcare (chronomedicine) are: 1). Development of universal criteria for the methodology of sampling, analysis and interpretation of the results of dynamic observations and 2). Development of a simple but accurate method for estimating endogenous circadian rhythm phase. The paper presents a comparative analysis of methods for assessing the phase of circadian rhythm and considers the prospects for the implementation of personalized chronodiagnostics and chronotherapy.