Major Depressive Disorder, Neuroimaging, Seasonal Affective Disorder
Conditions
Brief summary
Seasonal Affective Disorder (SAD) is a subtype of Major Depressive Disorder, characterized by a recurrent temporal relationship between the season of year, the onset and the remission of a major depressive episode. Estimates of the annual prevalence state that 1-6% of the population will develop SAD with the larger prevalences found at greater extremes in latitude. SAD is most likely triggered by the shortening photoperiod experienced in the winter months leading to a deterioration of mood. Recent cross-sectional neuroimaging studies have found cellular and neurotransmitter changes in response to seasonality, ultimately having an impact on the affect of patients. Conversly, this study aims to investigate the changes in neurocircuitry related to depression and euthymic states. Patients with SAD offer a unique ability to study these changes since they have predictable triggers for the onset of depression (i.e. the winter months) and remission (i.e. the summer months).
Interventions
DEVICEBright Light Therapy
Light box that emits light at 10,000 lux or higher and has been demonstrated to regulate circadian rhythm that is aberrant in the SAD population
Sponsors
Sunnybrook Health Sciences Centre
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
for SAD Cohort 1. Male or female between the ages of 18 to 65 years, inclusive 2. Patients who are able and willing to give consent and able to attend study visits 3. Agreement to use light therapy for four weeks 4. DSM-V diagnosis of seasonal affective disorder, at least 2 year history of the illness with a Structured Interview Guide for the Hamilton Depression Rating Scale-SAD version (SIGH-SAD) score ≥ 25 at screening
Exclusion criteria
for SAD Cohort 1. Current alcohol and/or substance use disorder 2. Use of cigarettes 3. Past or present psychiatric disorders (axis I and II) other than SAD 4. Taken medications approved and/or employed off-label for depression 5. Previous use of light therapy 6. Use of photosensitive medications 7. Montreal Cognitive Assessment score \< 24 8. Patients with standard contraindications for MR imaging. For example, non-MRI compatible metallic implants including cardiac pacemaker, size limitations etc. 9. Known intolerance or allergies to MRI contrast agent (Gadolinium or Magnevist) including advanced kidney disease 10. Severely impaired renal function (estimated glomerular filtration rate \<30ml/min/1.73m2) 11. Individuals who are not able or willing to tolerate the required prolonged stationary supine position during treatment 12. Pregnant and/or breastfeeding 13. Travelled to another a more southern latitude within 6 months of scan 14. Night shift workers 15. Are participating or have participated in clinical trial or research study in the last 30 days 16. Unable to communicate with investigator and/or staff 17. Diagnosis of a reading disability, dyslexia or significant learning disorder Inclusion Criteria for Unipolar Depression Cohort contraindications 1. Male or female between the ages of 18 to 65 years, inclusive 2. Patients who are able and willing to give consent and able to attend study visits 3. DSM-V diagnosis of major depressive disorder, with a Hamilton Depression Rating Scale score ≥ 22 at screening
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in connectivity | 12 months | Diffusion Tensor Imaging Scan |
| Changes in neural function | 12 months | Functional MRI Scan |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Memory | 12 months | California Verbal Learning Test. Score is conducted based on a propriety software based on the number of correctly recalled words after a list is administrated. |
| Executive Function | 12 months | Trail Makers Test B will be used to measure executive function. Test is scored based on time to complete.Average time is 75 seconds, deficient time is \>273 seconds |
| Depressive severity measured through the • Structured Interview Guide for the Hamilton Depression Rating Scale-SAD version | 12 months | Sigh-SAD measures Depressive Severity specifically in SAD patients. It contains 29 items, with the total score ranging from 0 to 29. Higher values in the scale indicate worse depression severity. Of the 29 items, 21 question (adapted from the Hamilton Depression scale) are used to determine typical depression severity, with an additional eight items for the atypical symptoms which are presented in seasonal affective disorder. The final score is summed, with equal weighting, to give the total score. |
| Blood Serum Metabolomic seasonal variation | 12 months | Blood will be drawn to assess different serum metabolites depending on the season. One blood draw will be taken in Winter, one in the summer. Over 3300 metabolites will be acquired from a single sample. |
| Concentration | 12 months | Digit Symbol Substitute Test will be used to measure concentration. Survey score is determined by the number of correct and incorrect responses |
Countries
Canada
Outcome results
None listed