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Effects of Season on Melatonin Secretion in Healthy Men and Women and Patients With Seasonal Affective Disorder
NCT00001485 · View on ClinicalTrials.gov ↗
Study Summary
As the seasons change during the course of the year, many animals show major changes in their behavior and physiology. Many of these changes are triggered by changes in the length of time each night that the pineal gland produces the hormone melatonin. Melatonin is produced for a longer time in winter when nights are long, than in summer when nights are short. Some researchers believe that melatonin may play a similar role in how season effects mood of patients with seasonal affective disorder. Seasonal affective disorder (SAD) or mood disorder with seasonal pattern is a condition where the normal biorhythm is disturbed during a season, especially autumn-winter. Patients may begin experiencing or experience worsening of depressive symptoms. Patients complain of being constantly tired, craving sugary foods, overeating, and over sleeping. Researchers have collected some preliminary data showing that the duration of nighttime melatonin secretion increases in winter and decreases in summer in healthy women, but not in healthy men. However, men diagnosed with SAD have shown longer duration of melatonin secretion in the winter, similar to the duration seen in healthy women. If these early findings are confirmed it may explain why SAD is more common in women than in men. The purpose of this study is to continue researching the differences in melatonin secretion over the seasons in healthy men and women, and to determine how these findings may apply to patients with SAD.
Conditions Studied
Study Locations (1)
Maryland
- National Institute of Mental Health (NIMH) — Bethesda
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 116 participants |
| Start Date | 1995-06 |
| Est. Completion | 2000-04 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT00001485
The ClinicalTrials.gov registry entry for NCT00001485 describes a study currently listed as completed. It is categorized as an unspecified phase, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 116 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is National Institute of Mental Health (NIMH), which has 317 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Seasonal Affective Disorder appearing as the primary indexed condition, and to 0 interventions. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT00001485 reports 1 study location spanning 1 distinct geographic area — top geographies include Maryland. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT00001485 about?
NCT00001485 is a clinical study titled "Effects of Season on Melatonin Secretion in Healthy Men and Women and Patients With Seasonal Affective Disorder". As the seasons change during the course of the year, many animals show major changes in their behavior and physiology. Many of these changes are triggered by changes in the length of time each night that the pineal gland produces the hormone melatonin. Melatonin is produced for a longer time in wint...
What is the current status of trial NCT00001485?
This trial is currently completed. The enrollment target is 116 participants. The study started on 1995-06. Estimated completion is 2000-04.
What conditions does trial NCT00001485 study?
This clinical trial studies the following conditions: Seasonal Affective Disorder. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
Who is sponsoring clinical trial NCT00001485?
This trial is sponsored by National Institute of Mental Health (NIMH), which has 317 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT00001485 being conducted?
This trial has 1 study location across Maryland. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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