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Examining the Effects of Antipsychotic Medications on Insulin Sensitivity

Acute Impact of Antipsychotics on Insulin Sensitivity: A Novel Human Model

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00895921
Enrollment
30
Registered
2009-05-08
Start date
2008-11-30
Completion date
2010-06-30
Last updated
2020-08-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diabetes

Keywords

Insulin Resistance, Antipsychotic Medications

Brief summary

This study will examine the effects of two different antipsychotic medications on control of blood sugar in people who are at risk of diabetes but mentally healthy.

Detailed description

Antipsychotic medications are those that treat the most severe psychiatric symptoms, such as hallucinations, paranoid thoughts, and delusions. Research shows that some of these medications may put people at a higher risk of metabolic derangements, such as insulin resistance. Certain antipsychotics, like clozapine and olanzapine, are associated with a higher risk of metabolic side effects than others, like aripiprazole and ziprasidone. Because people with schizophrenia may experience adverse side effects from switching antipsychotic medications and because it is difficult to find people with schizophrenia who do not have experience taking antipsychotics, this study will use people without psychiatric disorders who are at risk for diabetes in place of people with schizophrenia. The study will compare the effects of single doses of two antipsychotic medications, olanzapine and aripiprazole, on insulin action in this population. In addition to determining metabolic effects of these medications, this study will also seek to demonstrate the feasibility of using mentally healthy people at risk of diabetes as a substitute for people with schizophrenia in studying these effects. Participation in this study will last 4 weeks. Participants will first complete a screening visit that will include the following: an oral glucose tolerance test (OGTT), which involves a blood draw, consumption of a sugar drink, and then a second blood draw; a review of medical and psychiatric history, including use of medicines and psychiatric medications; and measurement of participants' height and weight. The second visit, scheduled 2 weeks after screening, will include a tracer-clamp study to test how participants' bodies handle sugar. The tracer-clamp study will be conducted over the course of one night and morning and will require participants to stay at the study location overnight. At 3 AM, participants will receive an intravenous line (IV) with a sugar solution. Just before 8 AM, they will receive a second IV in the opposite arm that will draw blood and monitor blood sugar levels. At 8 AM, participants will begin receiving insulin in the first IV; blood samples will be drawn and blood sugar levels will be monitored during this time to ensure they remain within a healthy range. At 11 AM, participants will receive an injection of an antipsychotic medication into their arm muscles. The antipsychotic, which will be randomly assigned, will be either olanzapine or aripiprazole. Participants will be monitored for 3 hours after receiving the injection of antipsychotic medication; during this time, more blood samples will be drawn, blood sugar levels will be monitored to ensure they are within a healthy range, and secondary medications will be available to counteract certain side effects of the antipsychotics. After 2 more weeks, participants will undergo a third study visit in which they repeat the OGTT.

Interventions

DRUGOlanzapine

Single intramuscular 10-mg dose

DRUGAripiprazole

Single intramuscular 9.75-mg dose

Sponsors

National Institute of Mental Health (NIMH)
CollaboratorNIH
Veterans Medical Research Foundation
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
40 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* Prediabetic, defined as 2-hour post-load serum glucose between 140 and 199 mg/dl on a 75-gram standard oral glucose tolerance test (OGTT) within the past 90 days * Family history of type 2 diabetes mellitus * Body mass index (BMI) between 25 and 35 kg/m2 * English speaker * Nonsmoker

Exclusion criteria

* History of Axis I mood, anxiety, or psychotic disorder, confirmed by Structured Clinical Interview for DSM-IV * Use of psychotropic drugs

Design outcomes

Primary

MeasureTime frameDescription
Change in Glucose DispositionMeasured over 6 hoursRatio of post-antipsychotic/pre-antipsychotic glucose disposition as measured using the hyperglycemic clamp technique. This method allows one to measure either how well an individual metabolizes glucose or how sensitive an individual is to insulin.

Secondary

MeasureTime frameDescription
Change in Percent of Insulin Suppression of Endogenous Glucose ProductionMeasured over 6 hoursRatio of Post-Antipsychotic/Pre-Antipsychotic Percent of Insulin Suppression of Endogenous Glucose Production
Akathisia6 hoursNumber of subjects reporting mild or greater complaints of akathisia after antipsychotic administration

Countries

United States

Participant flow

Participants by arm

ArmCount
Aripiprazole
Participants will receive an injection of aripiprazole during the tracer-clamp study. Aripiprazole: Single intramuscular 9.75-mg dose
15
Olanzapine
Participants will receive an injection of olanzapine during the tracer-clamp study. Olanzapine: Single intramuscular 10-mg dose
15
Total30

Baseline characteristics

CharacteristicOlanzapineTotalAripiprazole
Age, Continuous54.4 years
STANDARD_DEVIATION 5.97
51.17 years
STANDARD_DEVIATION 5.77
47.9 years
STANDARD_DEVIATION 5.57
Ethnicity (NIH/OMB)
Hispanic or Latino
3 Participants5 Participants2 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
12 Participants25 Participants13 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Glucose Disposition3.31 mg/kg/min
STANDARD_DEVIATION 1.35
3.60 mg/kg/min
STANDARD_DEVIATION 1.67
3.88 mg/kg/min
STANDARD_DEVIATION 1.99
Insulin Suppression of Endogenous Glucose Production (EGP)86.52 % suppression of EGP
STANDARD_DEVIATION 22.34
85.40 % suppression of EGP
STANDARD_DEVIATION 21.32
84.28 % suppression of EGP
STANDARD_DEVIATION 20.3
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
3 Participants7 Participants4 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
12 Participants23 Participants11 Participants
Region of Enrollment
United States
15 participants30 participants15 participants
Sex: Female, Male
Female
0 Participants0 Participants0 Participants
Sex: Female, Male
Male
15 Participants30 Participants15 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
1 / 157 / 15
serious
Total, serious adverse events
0 / 150 / 15

Outcome results

Primary

Change in Glucose Disposition

Ratio of post-antipsychotic/pre-antipsychotic glucose disposition as measured using the hyperglycemic clamp technique. This method allows one to measure either how well an individual metabolizes glucose or how sensitive an individual is to insulin.

Time frame: Measured over 6 hours

ArmMeasureValue (MEAN)Dispersion
AripiprazoleChange in Glucose Disposition1.18 ratio of post/pre valuesStandard Deviation 0.324
OlanzapineChange in Glucose Disposition1.42 ratio of post/pre valuesStandard Deviation 0.3
p-value: 0.04295% CI: [0.00943, 0.47605]t-test, 2 sided
Secondary

Akathisia

Number of subjects reporting mild or greater complaints of akathisia after antipsychotic administration

Time frame: 6 hours

ArmMeasureValue (NUMBER)
AripiprazoleAkathisia1 participants
OlanzapineAkathisia7 participants
Comparison: Comparison of akathisia rates between the two arms.p-value: 0.01295% CI: [0.095, 0.705]Chi-squared, Corrected
Secondary

Change in Percent of Insulin Suppression of Endogenous Glucose Production

Ratio of Post-Antipsychotic/Pre-Antipsychotic Percent of Insulin Suppression of Endogenous Glucose Production

Time frame: Measured over 6 hours

ArmMeasureValue (MEAN)Dispersion
AripiprazoleChange in Percent of Insulin Suppression of Endogenous Glucose Production1.0594 ratio of post/pre valuesStandard Deviation 0.519
OlanzapineChange in Percent of Insulin Suppression of Endogenous Glucose Production1.312 ratio of post/pre valuesStandard Deviation 0.642
p-value: 0.26995% CI: [-0.208, 0.714]t-test, 2 sided

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026