Effects of Season on Melatonin Secretion in Healthy Men and Women and Patients With Seasonal Affective Disorder

NCT00001485 | Completed

• 2 other identifiers: 95014995-M-0149
• Study Type: observational
• Target: 116
• Locations: 1 country
• Sites: 1

Brief 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

Seasonal Affective Disorder

Keywords

Chemical Mediators; Circadian Rhythms; Gender Differences; Melatonin; Photoperiodism; Seasonal Changes

Eligibility Criteria

• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

Normal volunteers must be free of psychiatric illnesses. Patients must meet the criteria of Rosenthal et al. for the diagnosis of SAD, as determined by a DSM IV diagnostic interview, and must be free of other major psychiatric illnesses. All subjects must be free of major medical illnesses and must not be taking medications on a regular basis. Patients must not test positive for antibodies to the AIDS virus.

Contact the study team to discuss eligibility requirements. They can help determine if this study is right for you.

Sponsors & Collaborators

• National Institute of Mental Health (NIMH): lead

Study Sites (1)

National Institute of Mental Health (NIMH)

Bethesda, Maryland, 20892, United States

Location

Related Publications (2)

• Wehr TA. The durations of human melatonin secretion and sleep respond to changes in daylength (photoperiod). J Clin Endocrinol Metab. 1991 Dec;73(6):1276-80. doi: 10.1210/jcem-73-6-1276.

  PMID: 1955509 BACKGROUND

• Wehr TA, Moul DE, Barbato G, Giesen HA, Seidel JA, Barker C, Bender C. Conservation of photoperiod-responsive mechanisms in humans. Am J Physiol. 1993 Oct;265(4 Pt 2):R846-57. doi: 10.1152/ajpregu.1993.265.4.R846.

  PMID: 8238456 BACKGROUND

MeSH Terms

Conditions

Seasonal Affective Disorder

Condition Hierarchy (Ancestors)

Depressive Disorder; Mood Disorders; Mental Disorders

Study Design

• Study Type: observational
• Sponsor Type: NIH

Study Record Dates

• First Submitted: November 3, 1999
• First Posted: December 10, 2002
• Study Start: June 1, 1995
• Study Completion: April 1, 2000
• Last Updated: March 4, 2008

Record last verified: 1999-08

Locations

US (1)