Chronobiology and Depression: Circadian Analytics as a Biomarker for Depressive Subtypes
Condition: Depression, Bipolar; Depression, Unipolar; Healthy
MeSH terms: Depression; Depressive Disorder; Bipolar Disorder
Study type: Observational

Summary: 
      An objective measure of treatment response could be a valuable new tool in the armamentarium
      of depression management, and this holds true for stimulation-based and pharmacological
      therapies alike. Hence, the Medibio Depression Monitoring Study will use the Medibio
      analytics platform to characterize autonomic, circadian, and sleep patterns before and during
      the initial 8 weeks of pharmacologic therapy for moderate-to-severe depression. The study
      will also explore any differences in these measures between treatment responders and
      non-responders, and between depression subtypes, including bipolar and unipolar depression.
      The study will also characterize longitudinal, ambulatory EEG measures throughout the
      observation period.
    

Detailed description: 
      This longitudinal, two-phase, three-arm, exploratory, observational study will use the
      Medibio analytics platform-with heart rate, activity, postural, and EEG data inputs-to
      characterize autonomic, circadian, and sleep patterns in unipolar depressed and bipolar
      depressed patients, which will include those with atypical and melancholic subtypes,
      undergoing the initial phase of standard pharmacological treatment, as well as in a
      non-depressed control group.

      Phase I will serve as a non-blinded, discovery phase for Medibio algorithm development.

      Phase II is optional, based upon sponsor/investigator assessment of results from Phase I.
      Phase II procedures will be identical to those in Phase I, with the exception that the
      Medibio algorithm will be blinded to clinical classification and status.

      The study cohorts will comprise: a) individuals initiating standard pharmacologic therapy
      with SSRIs for moderate-to- severe unipolar depression (will include subjects with
      melancholic and atypical subtypes), b) individuals initiating standard pharmacologic therapy
      with lamotrigine, lithium, or valproate for moderate or severe bipolar I or II depression
      (will also include subjects with melancholic and atypical subtypes), and c) non-depressed
      individuals who have been matched at the group level for age and gender (control subjects).
      Before the commencement of pharmacologic therapy (Baseline, t=0), at t=4 weeks, and at t=8
      weeks, heart rate, activity, postural data will be collected using the Zephyr BioPatch
      (Medtronic, Inc.) and ambulatory EEG data will be collected using the ZMachine Insight
      (General Sleep Corp). Recordings at each time point will consist of three 24-hour Zephyr
      recordings and three overnight ZMachine recordings.

      Clinical assessments will also be captured at the same time points, comprising both
      clinician-administered instruments [Clinical Global Impression (CGI), Hamilton Depression
      Rating Scale-17 (HAMD-17), and Young Mania Rating Scale (YMRS)] and subject self-rated
      instruments [Patient Health Questionnaire-9 (PHQ-9) and Quick Inventory of Depressive
      Symptomatology-Self Report (QIDS SR16)]. Zephyr and ZMachine data will be filtered based on
      quality (duration and completeness) and may be 'de-noised,' then will be processed by the
      Medibio platform to generate autonomic, circadian, and sleep metrics for use in the
      statistical analysis of study results.
    

Intervention name(s): Monitoring test
Intervention type(s): Other
Intervention description(s): Participants wear Zephyr BioPatch for three 24-hour periods and ZMachine Insight for three sleep periods.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Subjects will be enrolled at 1 site in the United States. Depressed subjects (bipolar and
        unipolar sub-types) will be recruited from outpatient clinics via direct physician referral
        and flyers. The study should be conducted with adequate representation of men and women; a
        minimum enrollment of 25% male subjects is desired. There are no enrollment restrictions
        based upon race or ethnic origin.