Cigarette Smoking in Smokers With and Without Schizophrenia
Primary Purpose
Tobacco Dependence, Schizophrenia
Status
Recruiting
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Sampling Research Cigarettes
Sponsored by
About this trial
This is an interventional basic science trial for Tobacco Dependence
Eligibility Criteria
Inclusion Criteria:
- Regular smoker of at least 10 cigarettes or cigarillos/day for at least 2 years
- For participants with schizophrenia: DSM-5 diagnosis of schizophrenia or schizoaffective disorder
- For participants with schizophrenia: Able to give informed consent
- For smokers with schizophrenia: No change in psychiatric medication or dosage in the last 4 weeks
Exclusion Criteria:
- Uncontrolled hypertension (resting systolic BP above 150 or diastolic above 95 mm Hg)
- Cardiovascular disease, such as history of myocardial infarction and ischemia, heart failure, angina, severe arrhythmias, or EKG abnormalities
- Severe asthma
- Chronic obstructive pulmonary disease
- Neurological illness, such as stroke, seizure disorder, neurodegenerative disease, or organic brain syndrome
- Mental retardation
- Alcohol or substance use disorder except nicotine within the last year
- Use of benztropine (Cogentin), varenicline (Chantix), bupropion (Wellbutrin, Zyban), or any type of nicotine replacement
- Pregnant or lactating
- For healthy control smokers: DSM-5 diagnosis of depression, bipolar disorder, ADHD, autism spectrum disorder, anorexia, bulimia nervosa, or any schizophrenia-spectrum disorder
- For healthy control smokers: immediate family history of psychosis
Sites / Locations
- Maryland Psychiatric Research CenterRecruiting
Arms of the Study
Arm 1
Arm 2
Arm Type
Other
Other
Arm Label
Smokers with schizophrenia
Smokers without schizophrenia
Arm Description
This is a diagnostic group, defined independently from this study.
This is a diagnostic group (i.e., no diagnosis of schizophrenia), defined independently from this study.
Outcomes
Primary Outcome Measures
Change in exhaled carbon monoxide
The concentration (ppm) of carbon monoxide (CO) in breath is measured by exhalation into a CO breathalyzer at the beginning of the Ad Libitum Smoking Session (baseline), and at the end eight hours later. The change value is obtained by subtracting each participant's baseline value from the end-of-session value.
Cigarette Discrimination Accuracy
Participants sample 4 cigarettes of type A and 4 cigarettes of type B in a double-blind manner and indicate for each cigarette if they think it is of type A or B. Two reference trials with cigarette type unblinded will be performed before the first and fifth sample cigarette. For each sampled cigarette, the score is either 1 (correct) or 0 (incorrect). Discrimination accuracy is calculated by averaging the eight scores for each participant.
Secondary Outcome Measures
Change in the number of research cigarettes smoked
In the Ad Libitum Smoking Session, participants can smoke as many research cigarettes as they wish. We quantify the number of cigarettes smoked in the first two hours and in the last two hours of the session and calculate the difference score by subtracting the number in the last two hours from that in the first two hours.
Difference in subjective state composite score
The difference in subjective state composite score is derived by transforming each subject's score on the Minnesota Nicotine Withdrawal Scale, the Affect-based Withdrawal Scale, the Questionnaire for Smoking Urges, and the modified Cigarette Evaluation Questionnaire into standard z-scores, calculating the difference between Research Cigarette A and B for each scale, and averaging the absolute values across scales.
Full Information
NCT ID
NCT04001114
First Posted
June 24, 2019
Last Updated
October 7, 2022
Sponsor
University of Maryland, Baltimore
1. Study Identification
Unique Protocol Identification Number
NCT04001114
Brief Title
Cigarette Smoking in Smokers With and Without Schizophrenia
Official Title
Cigarette Smoking in Smokers With and Without a Diagnosis of Schizophrenia
Study Type
Interventional
2. Study Status
Record Verification Date
October 2022
Overall Recruitment Status
Recruiting
Study Start Date
July 15, 2021 (Actual)
Primary Completion Date
June 2023 (Anticipated)
Study Completion Date
December 2023 (Anticipated)
3. Sponsor/Collaborators
Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
University of Maryland, Baltimore
4. Oversight
Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
Yes
5. Study Description
Brief Summary
Higher rates and severity of tobacco dependence in people with schizophrenia, as compared with the general population, contribute to the lower life expectancy seen in this population. Dependent tobacco smoking is controlled by how different aspects of cigarette smoking are perceived. There is evidence suggesting that people with schizophrenia differ in how they perceive cigarette smoking, which, if confirmed, would have implications for tailoring treatment interventions for smoking cessation in schizophrenia.
Detailed Description
The aim of the present study is to determine whether tobacco smoking in people with schizophrenia is governed by different aspects and effects of cigarette consumption. Smokers participating in this study either have no psychiatric diagnosis, or a diagnosis of schizophrenia or schizoaffective disorder. Over four study visits, participants will sample and compare different research cigarettes, complete questionnaires and concentration tasks, and smoke one type of research cigarette for eight hours while wearing a nicotine patch. By shaping our understanding of tobacco dependence in schizophrenia, the present project may redirect treatment development toward strategies tailored to the specific vulnerabilities of this population, which is among the most severely affected by its detrimental impact on health and life.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Tobacco Dependence, Schizophrenia
7. Study Design
Primary Purpose
Basic Science
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Model Description
We will compare participants with and without a diagnosis of schizophrenia. Study procedures are identical for the two groups.
Masking
ParticipantInvestigator
Masking Description
Participants compare different research cigarettes. Neither the participant nor the investigators know which cigarette is of which type.
Allocation
Non-Randomized
Enrollment
90 (Anticipated)
8. Arms, Groups, and Interventions
Arm Title
Smokers with schizophrenia
Arm Type
Other
Arm Description
This is a diagnostic group, defined independently from this study.
Arm Title
Smokers without schizophrenia
Arm Type
Other
Arm Description
This is a diagnostic group (i.e., no diagnosis of schizophrenia), defined independently from this study.
Intervention Type
Combination Product
Intervention Name(s)
Sampling Research Cigarettes
Intervention Description
Participants sample two research cigarettes, which differ in typical tobacco smoke constituents such as tar, nicotine, carbon monoxide, etc. In the Cigarette Discrimination Session, participants sample both types of cigarettes repeatedly, guess their identity (A or B) with regard to reference cigarettes, and rate their subjective effects. In the Ad Libitum Smoking Session, participants can smoke one of these cigarette types as much or as little as they like for eight hours.
Primary Outcome Measure Information:
Title
Change in exhaled carbon monoxide
Description
The concentration (ppm) of carbon monoxide (CO) in breath is measured by exhalation into a CO breathalyzer at the beginning of the Ad Libitum Smoking Session (baseline), and at the end eight hours later. The change value is obtained by subtracting each participant's baseline value from the end-of-session value.
Time Frame
One day (in the Ad Libitum Smoking Session), over an 8-hour time frame.
Title
Cigarette Discrimination Accuracy
Description
Participants sample 4 cigarettes of type A and 4 cigarettes of type B in a double-blind manner and indicate for each cigarette if they think it is of type A or B. Two reference trials with cigarette type unblinded will be performed before the first and fifth sample cigarette. For each sampled cigarette, the score is either 1 (correct) or 0 (incorrect). Discrimination accuracy is calculated by averaging the eight scores for each participant.
Time Frame
One day (in the Cigarette Discrimination Session), over a 6-hour time frame.
Secondary Outcome Measure Information:
Title
Change in the number of research cigarettes smoked
Description
In the Ad Libitum Smoking Session, participants can smoke as many research cigarettes as they wish. We quantify the number of cigarettes smoked in the first two hours and in the last two hours of the session and calculate the difference score by subtracting the number in the last two hours from that in the first two hours.
Time Frame
One day (in the Ad Libitum Smoking Session), over an 8-hour time frame.
Title
Difference in subjective state composite score
Description
The difference in subjective state composite score is derived by transforming each subject's score on the Minnesota Nicotine Withdrawal Scale, the Affect-based Withdrawal Scale, the Questionnaire for Smoking Urges, and the modified Cigarette Evaluation Questionnaire into standard z-scores, calculating the difference between Research Cigarette A and B for each scale, and averaging the absolute values across scales.
Time Frame
One day (in the Cigarette Discrimination Session), over a 6-hour time frame.
10. Eligibility
Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
60 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria:
Regular smoker of at least 10 cigarettes or cigarillos/day for at least 2 years
For participants with schizophrenia: DSM-5 diagnosis of schizophrenia or schizoaffective disorder
For participants with schizophrenia: Able to give informed consent
For smokers with schizophrenia: No change in psychiatric medication or dosage in the last 4 weeks
Exclusion Criteria:
Uncontrolled hypertension (resting systolic BP above 150 or diastolic above 95 mm Hg)
Cardiovascular disease, such as history of myocardial infarction and ischemia, heart failure, angina, severe arrhythmias, or EKG abnormalities
Severe asthma
Chronic obstructive pulmonary disease
Neurological illness, such as stroke, seizure disorder, neurodegenerative disease, or organic brain syndrome
Mental retardation
Alcohol or substance use disorder except nicotine within the last year
Use of benztropine (Cogentin), varenicline (Chantix), bupropion (Wellbutrin, Zyban), or any type of nicotine replacement
Pregnant or lactating
For healthy control smokers: DSM-5 diagnosis of depression, bipolar disorder, ADHD, autism spectrum disorder, anorexia, bulimia nervosa, or any schizophrenia-spectrum disorder
For healthy control smokers: immediate family history of psychosis
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Britta Hahn, Ph.D.
Phone
4104026112
Email
bhahn@som.umaryland.edu
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Britta Hahn, Ph.D.
Organizational Affiliation
University of Maryland, Baltimore
Official's Role
Principal Investigator
Facility Information:
Facility Name
Maryland Psychiatric Research Center
City
Catonsville
State/Province
Maryland
ZIP/Postal Code
21228
Country
United States
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Britta Hahn, Ph.D.
Email
bhahn@som.umaryland.edu
12. IPD Sharing Statement
Plan to Share IPD
No
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Cigarette Smoking in Smokers With and Without Schizophrenia
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