Short summary

Risk of obesity is increased in people with mental disease (MD) such as schizophrenia and bipolar disorder. Circadian disruptions (CD) are prevalent in people with MD and CD are similarly associated with obesity. The link between obesity, MD and CD remains unclear. We aim investigate CD in people with schizophrenia, people with bipolar disease, people with severe obesity, and normal-weight control subjects. This will be done by analysis of rhythmic expression of clock gene mRNA from hair samples

Rationale

Background and aim: People with mental illness (MI) have an increased risk of developing obesity (BMI above 30 kg/m2). As such, the prevalence of obesity is 80% higher for bipolar disorder, and 220% higher for schizophrenia.

Circadian disturbances (CD) (i.e., disturbed sleep-wake patterns) is a risk factor for obesity and people with obesity are more likely to experience poor sleep quality. In people with schizophrenia and bipolar disorders almost all measures of sleep quality and physiological sleep patterns are disturbed, even when disease is considered well-treated. The interactive effects between CD, obesity and MI remains largely unexplored. Thus, the aim of present study is to investigate different markers of CD in people with and without obesity and MI.

Description of the cohort

Four populations will be established: 1) People with obesity and schizophrenia (n=20) 2) People with BMI > 30 kg/m2 and bipolar disorder (n=20) 3) People with obesity without psychiatric disease (n=20) 4) People with obesity and no psychiatric disease or sleep disorders (n=20)

Participants will primarily be recruited from the South Danish Obesity Initiative(SDOI). SDOI is an initiative at the Hospital of South West Jutland. SDOI offer systematic assessments and treatment of people with obesity, A special focus in SDOI is the inclusion of people with obesity and psychiatric disease. Recently the SDOI-cohort was expanded to include normal-weight controls.

Data and biological material

Saliva samples, hair follicle mRNA, accelorometry,continuous glucose monitoring, bioimpedance, tests of physical function, questionnaire data, data from the patient journal,

Collaborating researchers and departments

Department of Clinical Biochemistry, Rigshospitalet i Glostrup

• Britt Lisette Corfixen
• Charlotte Sewerin Larsen

Steno Diabetes Center Odense, Odense University Hospital

• Rikke Kruse Sørensen
• Anni Schmidt Petersen
• Kurt Højlund

University of Surrey, Guildford, UK

• Derk-Jan Dijk

Department of Sports Science and Clinical Biomechanics, University of Southern Denmark

• Jan Christian Brønd