Optimizing Long-Term Outcomes for Winter Depression With CBT-SAD and Light Therapy

May 28, 2025 updated by: Kelly Rohan, University of Vermont

Optimizing Long-Term Outcomes for Winter Depression With CBT-SAD and Light Therapy: Confirming the Targets, Mechanisms, and Treatment Sequence

Major depression is a highly prevalent, chronic, and debilitating mental health problem with significant social cost that poses a tremendous economic burden. Winter seasonal affective disorder (SAD) is a subtype of recurrent major depression that affects 5% of the population (14.5 million Americans), involving substantial depressive symptoms for about 5 months of each year during most years, beginning in young adulthood.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Winter seasonal affective disorder (SAD) is a subtype of recurrent depression involving major depressive episodes during the fall and/or winter months that remit each spring. The central public health challenge in the management of SAD is prevention of winter depression recurrences. This application focuses on two SAD treatments that each work for some patients: light therapy (LT) and a SAD-tailored group cognitive-behavioral therapy (CBT-SAD). LT is the acute SAD treatment with the most substantial evidence to support its efficacy. Correction of circadian phase is LT's established target and mechanism. In our recently completed R01-level efficacy trial, post-treatment outcomes for CBT-SAD and LT were very similar, but CBT-SAD was associated with fewer depression recurrences over 2-year followup than LT (27.3% in CBT-SAD vs. 45.6% in LT). CBT-SAD engaged and altered a specific mechanism of action, seasonal beliefs, which improved at twice the rate during CBT-SAD compared to LT, and this improvement was associated with lower risk for recurrence following CBT-SAD. This confirmatory efficacy R01 will apply the experimental therapeutics approach to determine how each treatment works when it is effective and to identify the best candidates for each. We will ascertain whether theoretically-derived candidate biomarkers of each treatment's target and effect are prescriptive of better outcomes in that treatment vs. the other. Biomarkers of LT's target and effect include circadian phase angle difference (PAD) and the post-illumination pupil response (PIPR). Biomarkers of CBT-SAD's target and effect include pupil dilation and sustained gamma band EEG responses to seasonal words, which are hypothesized to reflect less engagement with seasonal stimuli following CBT-SAD and corroborate with the established target of seasonal beliefs. In addition to determining change mechanisms, we will test the efficacy of a "switch" decision rule upon recurrence to inform clinical decision-making in practice. We will randomize 160 adults with SAD to 6-weeks of CBT-SAD or LT in Winter 1; follow subjects in Winter 2; and, if a depression recurrence occurs, cross them over into the alternate treatment (i.e., switch from LT to CBT-SAD or CBT-SAD to LT). All subjects will be followed in Winter 3. Biomarker assessments will occur at pre-, mid-, and post-treatment in Winter 1, at Winter 2 followup (and again at mid-/post-treatment for those crossed-over), and at Winter 3 followup. Consistent with NIMH's priorities for demonstrating target engagement at the level of RDoC-relevant biomarkers, this work aims to confirm the targets and mechanisms of LT and CBT-SAD to maximize the impact of future dissemination efforts.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
141

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • Vermont
      • Burlington, Vermont, United States, 05405-0134
        • University of Vermont, Psychology Department

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Principle DSM-5 diagnosis of Major Depression, Recurrent, with Seasonal Pattern. -Meet Structured Interview Guide for the Hamilton Rating Scale for Depression-Seasonal Affective Disorder Version (SIGH-SAD) criteria for a current SAD episode (see below).
  • No use or stable use of antidepressants (i.e., a consistent dose of the same medication maintained for > 4 weeks with no plans to change).

Exclusion Criteria:

  • Current or past light therapy or CBT for SAD.
  • Presence of a comorbid Axis I disorder that requires immediate treatment (i.e., bipolar disorder, psychotic disorders, substance use disorder).
  • Acute and serious suicidal intent.
  • Planned absences of >1 week from the area through March.
  • History of conditions that are known contra-indications to LT, including conditions associated with toxicity of bright light to the retina (i.e., macular degeneration or any retinopathy).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Cognitive-Behavioral Therapy (CBT-SAD)
12 1.5-hour group sessions at a rate of 2 sessions per week over 8 weeks.
Behavioral: Cognitive-Behavioral Therapy (CBT-SAD)
12 group sessions over 6 weeks
Other Names:
  • CBT-SAD
Active Comparator: Light Therapy
6 weeks of daily light therapy at home, using a 10,000-lux light box beginning at 30 minutes upon waking, with dose subsequently adjusted per treatment algorithm.
Other: Light Therapy
10,000-lux initiated at 30 min upon waking and adjusted per treatment algorithm, continuing for 6 weeks

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Structured Interview Guide for the Hamilton Rating Scale for Depression-Seasonal Affective Disorder Version (SIGH-SAD)
Time Frame: past 1 week
Semi-structured interview of depressive symptoms
past 1 week
Beck Depression Inventory-Second Edition (BDI-II)
Time Frame: past 2 weeks
self-report measure of depressive symptoms
past 2 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Vermont

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
University of Maryland, Baltimore
University of Pittsburgh

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Kelly J Rohan, Ph.D., University of Vermont

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 1, 2018

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
February 28, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
February 28, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 28, 2018

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 1, 2018

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 2, 2018

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
June 3, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 28, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2024

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • R01MH112819 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Study data will be provided to the NIMH Data Archive

IPD Sharing Time Frame

After publication of the study results.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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