Melatonin and Nighttime Blood Pressure in African Americans--24 mg Study
Melatonin and Nighttime Blood Pressure in African Americans--24 mg Study
The purpose of this study is to test the effect of oral melatonin supplementation (24 mg per
 night for 4 weeks) on nighttime blood pressure in African Americans with a history of
 elevated nighttime blood pressure.
The main outcome of interest is the mean nighttime blood pressure. The investigator is also
 trying to see the mechanism of action of melatonin on blood pressure by analyzing data from
 sleep studies to see if melatonin lowers blood pressure by providing a better quality of
 sleep or is that independent of the quality of sleep.

 The investigator is also looking into the effect of melatonin on sympathetic nervous system
 by measuring urinary catecholamines.

 Finally, the investigator is looking into changes in vascular biology markers P-selectin and
 e-selectin) on Melatonin.
Inclusion Criteria:

 -  Males or females ages 18 to 64

 -  Prior history of elevated nighttime blood pressure (BP) ((systolic blood pressure
 (SBP) > 115mmHg))

 -  Taking no more than 2 antihypertensive medications

 -  African American (self-defined by the participant)

 Exclusion Criteria:

 -  Secondary forms of hypertension

 -  Presence of other diseases requiring treatment with BP lowering medication

 -  Known cardiovascular disease (including history of angina pectoris, heart failure,
 presence of a cardiac pacemaker, history of myocardial infarction or revascularization
 procedure, or history of cerebrovascular disease, including stroke and transient
 ischemic attacks)

 -  Diabetes mellitus (Type 1 or 2)

 -  Cancer/malignancy other than nonmelanoma skin cancer

 -  Primary renal disease

 -  Serum creatinine > 1.5 mg/dL in men or > 1.4 mg/dL in women

 -  Severe anemia

 -  Liver enzymes > 2.5 times upper limits of normal

 -  Hepatitis B, Hepatitis C, or HIV positive as assessed by questionnaire

 -  Current treatment with or regular use of calcium channel blocking agents,
 cyclooxygenase-2 inhibitors (COX2-I), oral contraceptives, estrogen, sildenafil,
 vardenafil, tadalafil, antidepressants, corticosteroids, or warfarin

 -  Current use of melatonin or any sleep aids containing melatonin

 -  Regular consumption (1 or more times per week) of: Vitamin methyl B12, St. Johns Wort,
 feverfew, black and white mustard seeds, wolf berry seed

 -  Severe Sleep apnea

 -  Night work

 -  Women who are pregnant, breast feeding, attempting conception, or planning to attempt
 conception over the next 6 months.