Association Between Smoking, Brain Activity, Genes, and ADHD

January 12, 2017 updated by: Jean Gehricke, University of California, Irvine

Smoking, Neurocircuitry and Genes in Adult ADHD

The study investigated the underlying mechanisms of smoking in young adults by examining the associations between smoking, brain activity, dopamine genes, and attention deficit hyperactivity disorder (ADHD).

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The study investigated the underlying mechanisms of smoking in young adults by examining the associations between smoking, brain activity, dopamine genes, and attention deficit hyperactivity disorder (ADHD). Four groups of young adults were recruited: (1) smokers with ADHD; (2) nonsmokers with ADHD; (3) normative control smokers; and (4) normative control nonsmokers. Smoking was assessed via questionnaires and salivary cotinine levels. Brain activity was examined via functional Magnetic Resonance Imaging (fMRI). Each nonsmoker underwent an fMRI scan during an experimental task consisting of mathematical problems. Smokers underwent two fMRI scans during similar experimental tasks under the following two conditions: (1) after smoking a cigarette and (2) after overnight abstinence. The association between the DRD4-7 repeat allele and smoking was explored.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
89

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • California
      • Santa Ana, California, United States, 92705
        • 2500 Red Hill Avenue

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 45 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Commuity sample

Description

Inclusion Criteria:

  1. Smokers with ADHD

    • Cigarette smoking for the last year
    • ADHD diagnosis

  2. Nonsmokers with ADHD

    • No history of regularly smoking cigarettes
    • ADHD diagnosis

  3. Normative control smokers

    • Cigarette smoking for the last year
    • No history and diagnosis of ADHD

  4. Normative control nonsmokers

    • No history of regularly smoking cigarettes
    • No history and diagnosis of ADHD

Exclusion Criteria:

  • Children under the age of 18
  • Adults above the age of 45
  • Pregnancy or planning to become pregnant
  • Any major medical illness
  • Any mental disorders that require medication (except stimulant medication)
  • Any contraindications to fMRI scanning
  • Not speaking English

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Smokers with ADHD
Smokers with ADHD participated in one overnight abstinence condition (withdrawal) and one smoking condition (smoking the first cigarette of the morning).
Behavioral: Cigarette smoking
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking a cigarette.
Behavioral: Abstinence
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking abstinence.
Nonsmokers with ADHD
Nonsmokers with ADHD participated in one condition.
Behavioral: Abstinence
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking abstinence.
Control smokers
Control smokers participated in one overnight abstinence condition (withdrawal) and one smoking condition (smoking the first cigarette of the morning).
Behavioral: Cigarette smoking
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking a cigarette.
Behavioral: Abstinence
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking abstinence.
Control nonsmokers
Control nonsmokers participated in one condition.
Behavioral: Abstinence
Participants had an fMRI scan during an experimental task consisting of mathematical problems after smoking abstinence.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Brain Activity
Time Frame: One MRI session for nonsmokers and two MRI sessions for smokers
BOLD z-score of smokers with ADHD after abstinence/smoking a cigarette, control smokers after abstinence/smoking a cigarette, nonsmokers with ADHD, and control nonsmokers. All participants performed a mathematical task in the MRI scanner. Higher BOLD z-scores indicate greater brain activation.
One MRI session for nonsmokers and two MRI sessions for smokers

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
DRD4 Genotype
Time Frame: one time blood draw
one time blood draw
Salivary Cotinine
Time Frame: Once per week for 4 weeks
Average level of salivary cotinine over all time points (microgram/milliliter)
Once per week for 4 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of California, Irvine

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institute on Drug Abuse (NIDA)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jean-G. Gehricke, Ph.D., M.A., University of California, Irvine

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 1, 2009

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2016

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 1, 2016

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
June 4, 2009

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 5, 2009

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 8, 2009

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 13, 2017

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 12, 2017

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2016

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • HS 2009-6740
  • K01DA025131 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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