Effects of Melatonin Supplementation on Renal Physiology in a Habitual Sleep Restricted Population.

The investigators will recruit individuals from the Boston area who meet the inclusion and exclusion criteria. The investigators will include both men and women and all races and ethnicities. The only exception will be women who are pregnant because certain medications used during the inpatient evaluations (e.g., nitroglycerine), and certain study medications (i.e., captopril) are contraindicated during pregnancy.

Participant Enrollment

Responders to advertisements will be pre-screened by telephone to obtain a body mass index (BMI) estimate and a medical history to gauge potential eligibility. For participants who may be eligible following this phone query, the basic study schema will be described to identify those who remain interested in participation after learning the duration, inpatient requirements, and potential medication use. These individuals will then be invited to attend an outpatient screening visit.

The pilot study is a double-blind, placebo-controlled randomized trial, in which 16 subjects with obesity (body mass index [BMI] ≥30 kg/m2), pre-diabetes (hemoglobin A1C [HbA1C], 5.7-6.4%), and self-reported short sleep duration (<7 hours/night) are randomly assigned 1:1 to receive either placebo or 2 mg of controlled-release melatonin, taken orally every evening 1 hour before bed for 6 weeks. All subjects will be asked to extend their sleep time by one hour during the 6 week period between inpatient visits. Endpoints will be measured at both the baseline and 6-week inpatient visits.

Screening Visit: Screening visits will take place at the Brigham and Women's Outpatient Center for Clinical Investigation During the outpatient screen, Dr. McMullan will explain the study in detail, review the consent form, and answer questions. After obtaining written informed consent for participation, a history and physical examination will be performed in order to initially judge eligibility based upon the criteria set out in that section of this record. Participants deemed potentially eligible based upon the screening history and exam will undergo phlebotomy and analysis for HbA1c, serum chemistries and glucose, and complete blood count (CBC) to confirm eligibility using the criteria presented in the table.