In summary , the current meta- analysis demonstrated that melatonin supplementation  significantly decreased SBP and DBP in patients with metabolic disorders .
The current systematic review and meta- analysis of r and omized controlled trials ( RCTs ) was conducted to evaluate the potential effect of melatonin supplementation on  blood pressure in patients with metabolic disorders .
Melatonin for nondippers with coronary artery disease: assessment of blood pressure profile and heart rate variability
The aim of this study was to assess the effects of 5 mg melatonin before sleep in patients with coronary artery disease ( CAD ) and with an abnormal circadian pattern of blood pressure ( BP ) on changes in circadian BP profile and heart rate variability ( HRV ) . Sixty patients with CAD , nondippers aged 48–80 years ( male 75 % ) , were included . In addition to previous treatment , they were r and omly allocated to melatonin or placebo . After 90 days , a second 24-h BP monitoring was carried out . Each patient had two sessions ( before r and omization and at the end of study ) of 24-h ECG monitoring to assess the changes in HRV . Inclusion of melatonin led to BP pattern normalization in 35 % of patients in the melatonin group and in 15 % of controls ( P=0.609 ) . This effect was reached not only by a decrease in nighttime BP , but also by an increase in daytime BP ( significant in the melatonin group ) . A nonoptimal effect for BP profile was observed in 12.5 % of patients : extreme- or reverse dippers . In patients with conversion from nondippers to dippers ( responders ) , an increase in st and ard deviation of normal-to-normal intervals between initial and final HRV analyses was observed . Nonresponders represented an increase in the mean circadian heart rate . To avoid nonoptimal effects , the inclusion of melatonin in pharmacotherapy of patients with CAD should be based on monitoring of circadian BP profile , before and during treatment . As melatonin caused not only a nocturnal decrease in BP but also a daytime increase , it should not be recommended in patients with ‘ high normal ’ values of BP because of the danger of induction of arterial hypertension
In summary , the current meta- analysis demonstrated that melatonin supplementation  significantly decreased SBP and DBP in patients with metabolic disorders .
The current systematic review and meta- analysis of r and omized controlled trials ( RCTs ) was conducted to evaluate the potential effect of melatonin supplementation on  blood pressure in patients with metabolic disorders .