Clinical trial NCT03996356: Clozapine Induced Weight Gain
Official title: Clozapine Induced Weight Gain: A Pharmacogenetic Study
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Weight Gain
Antipsychotic Agents
Pharmacogenetics
Lead sponsor: Cwm Taf University Health Board (NHS)
Sponsor class: OTHER_GOV
First posted: 2019-06-24
Enrollment: 160
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Patients on clozapine treatment

Brief summary: Clozapine is prescribed to patients with psychosis in whom other treatments have not worked. Research has shown, however, that clozapine may be associated with weight gain and abnormal blood sugar levels in some patients. There is strong evidence to suggest that genetic variation between individuals plays an important role in the development of these side effects in response to the medication. Our research aims to evaluate the effects of two genes and the blood level of clozapine on side-effects such as weight changes and blood sugar levels in patients receiving clozapine treatment. From out-patient clinics in Cwm Taf UHB, the investigators aim to recruit 160 patients who are taking clozapine; collect information/ measurements from recruits relating to size/ weight/ BMI, risk of diabetes and blood samples to measure markers of blood sugar, fat/lipids, clozapine and its breakdown products, blood cells and variants of two specific genes. From this information the investigators will be particularly interested to understand if there is any association between the variation in these two genes with weight gain or changes in blood sugar, in patients taking clozapine.


Eligibility criteria: Inclusion Criteria:

* Age 18 years or over
* Taking/compliant with clozapine antipsychotic medications.
* Patients meeting the ICD-10 criteria for a diagnosis of schizophrenia, schizoaffective or borderline personality disorders.

Exclusion Criteria:

* History of current alcohol/illicit substance dependency.
* Unable/ unsuitable to complete the study protocol e.g. acutely ill, suicidal or aggressive patients.
* Unable to consent to the study.

Primary outcomes:
measure: Body-mass index (BMI)
timeFrame: 12 months
measure: Leptin gene promoter region single nucleotide polymorphisms (SNPs) (rs7799039)
timeFrame: 12 months
measure: Serotonin 5-HT 2C receptor gene single nucleotide polymorphisms (SNPs) (rs3813929)
timeFrame: 12 months
Secondary outcomes:
measure: Blood haemoglobin A1c concentration
timeFrame: 6 months
measure: Waist:hip ratio
timeFrame: 12 months
measure: Lipid profile
timeFrame: 12 months
measure: Clozapine side effects assessment by Clinical Global Impression (CGI) scale
timeFrame: 12 months
measure: Clozapine:nor clozapine ratio
timeFrame: 12 months
Other outcomes:
Locations:
city: Merthyr Tydfil
country: United Kingdom
facility: Cwm Taf University Health Board
state: Wales
Study officials:
affiliation: Cwm Taf Morgannwg UHB
name: Brian P Tennant, PhD
role: PRINCIPAL_INVESTIGATOR
References:
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