Effects of Antipsychotics on Eating and Food Craving in People With Schizophrenia
Condition: Schizophrenia; Obesity
MeSH terms: Schizophrenia
Study type: Observational

Summary: 
      Background:

      - Although second-generation antipsychotic medications have fewer serious side effects and
      complications than first-generation ones, they are strongly associated with weight gain for
      reasons that are as yet unknown. Comparing the effects of second-generation antipsychotics
      with a high weight-gain liability (HWGL) low weight-gain liability (LWGL) antipsychotics may
      provide more information on which medications are best suited for different individuals.
      Researchers are interested in studying how people taking various antipsychotics compare with
      controls in regard to food craving and eating behavior. This knowledge should help to guide
      practitioners when advising patients about the weight-gain effects of these medications.

      Objectives:

      - To examine eating behavior and food craving in patients with schizophrenia who are taking
      HWGL antipsychotics compared with those taking LWGL antipsychotics and with healthy controls
      taking no antipsychotics.

      Eligibility:

        -  Individuals between 18 and 45 years of age who have been diagnosed with schizophrenia or
           a related disorder, have a body mass index between 25 and 29.9, and have never had an
           eating disorder.

        -  Healthy individuals between 18 and 45 years of age who have a body mass index between 25
           and 29.9 and have never had an eating disorder.

      Design:

        -  This study involves an initial screening visit and four study visits.

        -  Participants will be screened with a medical history and physical examination, as well
           as questionnaires about stress levels, food cravings, smoking, exercise, and eating
           habits; a taste test; and saliva collection (to measure stress hormones).

        -  Visit 2: Participants will have an optional overnight stay, and will provide blood
           samples before having a breakfast beverage and answering questions about tiredness,
           anxiety, hunger, and alertness during a 1.5 hour session.

      Visit 3: Participants will have an optional overnight stay and a light breakfast, followed by
      blood draws and questions about hunger and food cravings.

      Visit 4: Participants will have an optional overnight stay, followed by questions about food
      preference. Participants will not be allowed to eat until mid-morning of the next day.

      Visit 5: Participants will eat normally before arriving at the research site, and will have
      tests to measure food craving and questionnaires about mood and feelings.
    

Detailed description: 
      Objective

      Some second-generation antipsychotics, such as olanzapine and clozapine, seem especially
      prone to induce metabolic complications and substantial increases in weight. The mechanisms
      of these side effects are unknown, but may include antagonism at histamine H1 receptors. We
      will refer to olanzapine and clozapine as antipsychotics with a high weight-gain liability
      (HWGL). The primary aim of this project is to examine eating and food craving in patients
      with schizophrenia who are taking HWGL antipsychotics compared with those taking LWGL
      antipsychotics (mid- to high-potency first-generation antipsychotics, aripiprazole, or
      ziparasidone) and compared with healthy controls taking no antipsychotics. The antipsychotics
      we are classifying as LWGL group do not have appreciable H1 receptor antagonism. We will
      exclude participants taking antipsychotics that have middling degrees of H1 receptor
      antagonism (e.g. quetiapine).

      This study will help us understand how people with schizophrenia differ from controls on
      eating and food craving, as well as the effects of different classes of antipsychotics. This
      knowledge should help to guide practitioners when advising patients about the weight-gain
      effects of these medications. For example, if we find that participants on HWGL
      antipsychotics tend to crave high-fat foods, practitioners can work with patients to
      anticipate and mitigate this side effect.

      Study population. The study population will be in- or outpatients with a DSM-IV diagnosis of
      schizophrenia or schizoaffective disorder stabilized on either olanzapine or clozapine (HWGL
      antipsychotics) (N=20), aripiprazole, ziprasidone, or a first-generation antipsychotic (LWGL
      antipsychotics) (n=20), and normal controls (people with no Axis I psychiatric disorder
      taking no antipsychotic medication) (n=20), for a total of 60 participants. All participants
      will be between the ages of 18 to 45 years and considered overweight (BMI greater than or
      equal to 25 and less than or equal to 29.9 kg/m(SqrRoot)). The pediatric population has been
      excluded to rule out certain hormonal effects (e.g. puberty) on eating behavior. A BMI range
      encompassing participants that are overweight was selected to maximize recruitment and to
      minimize confounding effects of BMI on eating behavior. Exclusion criteria will include
      weight-related conditions and current dietary restrictions.

      Experimental design and methods. In a between-subjects design, the three study groups will be
      compared in terms of four domains of eating behavior: (1) food craving, (2) satiety
      signaling, (3) meal size (satiation), and (4) food preferences. Assessments will occur during
      five study visits (including an initial visit for consenting and screening).

      Outcome measures: Primary outcome measures will include a preload-test meal paradigm
      (satiety), meal size perception and satiation, food preference, food craving, and gustatory
      functioning. Secondary measures will include: Weight and Eating Assessment questionnaire,
      Recent Physical Activity Questionnaire (RPAQ), State Trait Anxiety Inventory (STAI), Exercise
      Motivations Inventory (EMI), Childhood Trauma Questionnaire, Tobacco Craving
      Questionnaire-Short Form (TCQ-SF), Fagerstrom Test for Nicotine Dependence (FTND), BMI,
      hip/waist measurements, and fasting blood work: CBC, CMP14, lipid panel, leptin, ghrelin,
      adiponectin, and thyroid panel.
    

Time perspective: Prospective
Keywords: High Weight Gain Liability (HWLA); Antipsychotic; Obesity; Low Weight Gain; Schizophrenia; Food Craving