SYNCED - SYNChronized Eating in Bipolar Depression Study

The investigators will consider the intervention feasible if 70% of participants complete follow-up.

The investigators will consider the intervention feasible if 70% of participants complete follow-up.

The investigators will consider the intervention acceptable if participant adherence to the intervention is at least 70% (i.e. participants adhere to the TRE intervention 40 days out of 56 days); ii) at least 50% of participants approached about the study agree to participate.

The investigators will consider the intervention acceptable if at least 50% of potential participants approached about the study agree to participate.

The Montgomery-Åsberg Depression Rating Scale (Structured Interview Guide) (MADRS) is a 10-item observer-rated scale to assess the severity of depressive symptoms within the last 7 days. Possible total score range is 0-60. Score of: 0-8 indicates remission/absent symptoms; 9-17 mild depression, 18-34 moderate depression; and 35-60 severe depression.

A 16-item self-report that assess subjective cognitive dysfunction (including executive function, processing speed, working memory, verbal learning and memory, attention/concentration and mental tracking) in bipolar disorder. Measured on a 4-point Likert scale ranging from never (0) to always (3). Scores range 0-48 with higher scores indicating worse cognitive dysfunction.

The Screen for Cognitive Impairment in Psychiatry (SCIP) is a brief clinician administered evaluation of cognitive deficits including working memory, immediate and delayed verbal list learning, verbal fluency, and psychomotor speed. Score is calculated as a sum of 5 subgroups, with subgroup 3 having no limit to the total score. Total score ranges from 0 with no upper limit, with lower scores showing more cognitive impairment. These scores are interpreted in the following manner: total score of < 75 suggest mild impairment, score of < 65 indicate moderate impairment, and score of < 55 indicate severe impairment.

The Hamilton Anxiety Rating Scale (HAM-A) is a 14-item semi-structured observer-rated interview evaluating symptoms of anxiety. Each item is scored 0 (not present) to - 4 (very severe). Scores range 0-56 with higher scoring indicating worse severity of anxiety symptoms. These scores are interpreted in the following manner: scores of 0-7 indicate remission/symptom absence, 8-14 mild anxiety, 15-23 moderate anxiety and 24-56 severe anxiety.

Self-reported measurement of the severity of anxiety symptoms experienced within the last two weeks. It consists of 7 scored items and one follow-up question. Each of the 7 scored items generates a value from 0 (not at all) to 3 (nearly every day), yielding a total score ranging from 0 to 21, with higher scores indicating more severe symptoms of anxiety. These scores are interpreted in the following manner: a score of 0-4 indicates little or no anxiety, a score of 5-9 indicates mild anxiety, a score of 10-14 indicates moderate anxiety, and a score of 15-21 indicates severe anxiety. Generally, a score of 10 or above is considered to be a clinical cutoff implying that the respondent may be suffering from a general anxiety disorder.

A 21-item observer-rated measure that assess five areas related to biological rhythms (sleep, activity, social aspect, diet, and predominant rhythm (chronotype)). All items are evaluated on a 4-point likert scale ranging from 1-4, with higher scores indicating greater disturbance. Total score ranges from 21-84.

The Pittsburgh Sleep Quality Index Questionnaire is self-administered questionnaire designed to evaluate sleep quality consisting of 18 items that in turn are comprised of seven components, which include subjective sleep quality, sleep duration, sleep onset, habitual sleep efficiency, sleep disturbances, use of sleeping medications and daytime dysfunction. Each weighted equally on a 0-3 scale to be summed to yield a global PSQI score, which ranges between 0 and 21, where the higher the scores, the worse the sleep quality. The investigators will only be using questions 1-4 and 6 (reduced PSQI).

This questionnaire has 19 questions, each with a number of points. Scores can range from 16-86. Scores of 41 and below indicate "evening types." Scores of 59 and above indicate "morning types." Scores between 42-58 indicate "intermediate types."

A numeric ranking between 0 and 100 that summarizes the clinician's view of the patient's current degree of impairment in terms of psychosocial and occupational or educational function. Higher scores indicate better functioning. Normal functioning typically ranges from 70-100.

The CGI-BP I&S is a measure of CGI-I and CGI-S specifically validated for bipolar disorder. The CGI-BP-S scale provides a brief assessment of the severity of a patient's mental illness at baseline and following treatment. CGI-I and CGI-S are each rated on a likert scale of 0-7 (0, not assessed, 1-7 normal to most extremely ill). The CGI-BP-I scale provides a brief assessment of a patient's overall mental state following treatment, and whether or not it is due entirely to the experimental treatment.

The FAST is a brief clinician-reported scale which assess psychosocial dysfunction across multiple domains (autonomy, occupational functioning, cognitive functioning, financials, interpersonal relationships, and leisure time) in people with bipolar disorder. Aspects of functioning are rated on a 4-point Likert scale of 0 (no difficulty) to 3 (severe difficulty) with total scores ranging from 0-72. Higher scores indicate more dysfunction.

A brief 12-item self report that examines quality of life in people living with bipolar disorder over the past 7 days. Experiences of quality of life are rated on a 5-point Likert scale ranging from 1 (Strongly disagree) to 5 (Strongly Agree). Total scores range from 12-60 with higher scores indicating better quality of life.

The Young Mania Rating Scale is used to evaluate the severity of manic symptoms at baseline and over time in individuals with mania. It is an 11-item scale and total score ranges from 0 to 60 where higher scores indicate more severe mania, thus, a negative change (or decrease) from baseline indicates a reduction (or improvement) in manic symptoms. Total score ≤12 indicates remission (13-19=minimal symptoms; 20-25=mild mania, 26-37=moderate mania, 38-60=severe mania).

Using wrist actigraphy, the investigators will collect data on two 24-hour sleep-wake cycles. The validated wrist actigraphy monitor will collect non-invasive, wireless continuous monitoring of movements and ambient light (in the blue, green and red spectrum). These two measures will be combined to extract sleep estimates and parameters of the 24-hour activity-rest cycle before and after the intervention. Changes in the circadian rhythms (hours of sleep or movement) will be compared pre- and post between treatment groups.

The investigators will collect blood samples and measure levels of C-reactive protein (CRP) before and after the intervention. CRP is an inflammation marker and measured in mg/L.

The investigators may collect blood samples and measure levels of cytokines including interleukins (IL) -6, IL-10, IL-1B and tumor necrosis factor alpha (TNF-a) before and after the intervention. IL-6, IL-10 and TNF-a are inflammatory cytokines and IL-10 is an anti-inflammation cytokine. All cytokines are measured in pg/mL.

The investigators will collect blood samples to evaluate changes in red blood cell count (RBC) as part of changes in hematology before and after intervention. This will be done as part of a complete blood count (CBC) will be conducted to investigate changes in various blood components. RBC is measured in x10*12/L

The investigators will collect blood samples to evaluate changes in hemoglobin (Hgb) as part of changes in hematology before and after intervention. This will be done as part of a complete blood count (CBC) will be conducted to investigate changes in various blood components. Hgb is measured in g/L.

The investigators will collect blood samples to evaluate changes in hematocrit (Hct) as part of changes in hematology before and after intervention. This will be done as part of a complete blood count (CBC) will be conducted to investigate changes in various blood components. Hct is measured in L/L..

The investigators will collect blood samples to evaluate changes in lymphocyte count as part of changes in hematology before and after intervention. This will be done as part of a complete blood count (CBC) will be conducted to investigate changes in various blood components. Lymphocyte count is measured in x10*9/L.

The investigators may collect blood samples to evaluate changes in blood chemistry before and after the intervention. The test will include fasting glucose, fasting lipid profile (includes measures of high-density and low-density lipoprotein cholesterol, total cholesterol and triglycerides). All blood chemistry measures are measured in mmol/L.

The investigators may collect blood samples to evaluate changes in liver function by measuring alkaline phosphatase (ALP), aspartate transferase (AST), alanine transaminase (ALT), gamma-glutamyl transferase (GGT) before and after the intervention. All measures are reported in U/L.

The investigators may collect blood samples to evaluate changes in liver function by measuring total bilirubin before and after the intervention. This is measured in umol/L.

The investigators will collect blood samples to evaluate changes in blood chemistry by measuring total serum creatinine before and after the intervention. This is measured in umol/L.