19 May Melatonin May Improve Blood Pressure Control Through Circadian Rhythm Regulation
MedicalResearch.com Interview with:
Dr. Denis Gubin
The Tyumen Medical University
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Gubin: The older we get, the more likely our circadian rhythms are disrupted. For example, blood pressure, BP, not only tends to increase but as well become more irregular.
One of the possible causes is an age-dependent deficit of endogenous melatonin production. We have shown that exogenous melatonin helps to ameliorate both trends – lowers blood pressure and also stabilizes and synchronizes blood pressure and heart rate variability.
MedicalResearch.com: What should clinicians and patients take away from your report?
Dr. Gubin: First, low-dose melatonin (1.5 mg – half of 3 mg tablet, each day for successive 2 weeks at 10:30 p.m.) significantly reduced blood pressure. What is important, the hypotensive effect was dependent on time. The maximum systolic blood pressure lowering effect of melatonin falls between 3:00 and 8:00 in the morning, the time of the highest risk of heart attacks and strokes. Nighttime and morning BP decreased more profoundly on average -8/3.5 mm Hg for SBP/DBP, respectively. Moreover, the higher the mean systolic BP was during the first week, the more it dropped on the second week of melatonin administration. Melatonin also decreased the overall variability in blood pressure.
Melatonin was effective in synchronizing disrupted circadian rhythms of blood pressure, heart rate and body temperature, making these circadian rhythms smoother and less irregular. None of these effects was found in 34 placebo treated seniors, thus ruling out the possibility that rhythms could be improved just because of regular schedule and presence of medical personal who took measurements.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Gubin: Melatonin can be of great value for aged people suffering from hypertension as an adjuvant substance complementing basic medication, as it stabilizes circadian BP, heart rate profiles and their phase relationships. The improvement of circadian pacemaker functions may also provide a new strategy in the treatment of hypertension. It is known, however, that melatonin is not necessarily lowers with age. In some seniors high nocturnal melatonin values are preserved. We suppose that those with deficit will benefit most. Efficiency of exogenous melatonin in attenuating age-dependent signs of circadian disruption of overt blood pressure, HR and BT circadian rhythms may as well dependent on additional factors such as chronotype, Alzheimer disease and type 2 diabetes mellitus.
MedicalResearch.com: Is there anything else you would like to add?
Dr. Gubin: Chronotherapy is a novel strategy in treatment of many diseases. Results of MAPEC study, lead by Dr., Ph.D. Ramon Hermida of University of Vigio in Spain, proved that evening medication of hypertension is generally superb to the morning as nighttime BP must be controlled first and foremost. Next step is truly personalized approach when timing of medication is chosen just for you in accordance with you rhythms. As we have shown in another studies, such strategy is beneficial when circadian rhythms are compromised (shift-work, Arctic roundabouts, age-related disruption and due to light pollution/light at night, perhaps). To implement such personalization, regular BP rhythm should be restored first and melatonin should help.
Curr Aging Sci. 2016;9(1):5-13.
Daily Melatonin Administration Attenuates Age-Dependent Disturbances of Cardiovascular Rhythms.
Gubin DG1, Gubin GD, Gapon LI, Weinert D.