Melatonin and the Metabolic Syndrome (MetSyn)

Melatonin is a hormone that regulates some body functions, including the sleep/wake cycle. Some people take melatonin supplements (over the counter) for promoting sleep. Some studies suggest that melatonin may help improve blood pressure, glucose levels, blood lipid levels, which are components of "the metabolic syndrome." This trial seeks to compare the effects of melatonin supplementation versus placebo on these factors in patients with metabolic syndrome.

The primary purpose of this Phase II crossover design trial is to examine the safety and efficacy of 8mg of melatonin taken one hour before bedtime compared to a placebo treatment to improve at least one of the five components associated with the metabolic syndrome.

• Drug: Melatonin
  8 mg
• Drug: Placebo
  Placebo

• Experimental: Melatonin
  Melatonin 8mg one hour before bedtime for 10 weeks
  Intervention: Drug: Melatonin
• Placebo Comparator: Placebo
  placebo
  Intervention: Drug: Placebo

Inclusion Criteria:

1. Age 30-79 years.
2. Diagnosed with metabolic syndrome according to ATP-III criteria.
3. Availability for six months after enrolling in the study.

Exclusion Criteria:

1. Inability to understand informed consent and to cooperate with study procedures.
2. Supplemental intake of melatonin.
3. Current smoking.
4. Current use of calcium channel blockers.
5. Current, planned, or recent (12 months) participation in another clinical trial.
6. Women who are pregnant, breast-feeding, attempting conception, or planning to attempt conception over the next 6 months.

7. Presence of any of the following diagnosed health conditions:

   • Active malignancy other than nonmelanoma skin cancer (current therapy for this malignancy,diagnosis within five years of enrollment, recurrence within five years of enrollment, or metastasis)
   • Uncontrolled hypothyroidism or hyperthyroidism
   • Recent (< 1 year ago) history of heart attack, bypass surgery, angioplasty, or stroke
   • Heart failure (New York Heart Association functional class 3 or 4)
   • On renal dialysis
   • Immunosuppressive therapy (systemic corticosteroids, azathioprine, methotrexate, cyclophosphamide,
   • etc.) or an immunodeficiency syndrome
   • Narcotic or alcohol dependence
   • Obstructive sleep apnea (OSA) , defined either by previous diagnosis (with or without use of nasal CPAP), or by a score of 0.80 or higher on the MAP (Multivariate Apnea Prediction), a validated screening algorithm with high positive and negative predictive value for identifying OSA.
8. Shift-workers.