Chronic Cannabis Smoking, Oxidative Stress and the Pulmonary Innate Immune Response
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ClinicalTrials.gov Identifier: NCT02480283 |
Recruitment Status :
Recruiting
First Posted : June 24, 2015
Last Update Posted : June 21, 2021
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Condition or disease | Intervention/treatment |
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Cannabis Smoking Oxidative Stress | Procedure: Bronchoscopy Radiation: Chest X-ray Procedure: Venipuncture Procedure: Intravenous Catheter |

Study Type : | Observational |
Estimated Enrollment : | 100 participants |
Observational Model: | Cohort |
Time Perspective: | Retrospective |
Official Title: | Chronic Cannabis Smoking, Oxidative Stress and the Pulmonary Innate Immune Response |
Actual Study Start Date : | November 11, 2015 |
Estimated Primary Completion Date : | July 2026 |
Estimated Study Completion Date : | July 2027 |

Group/Cohort | Intervention/treatment |
---|---|
Control
Subjects aged 18 to 55 who have never used cannabis by self report (validated via urine drug screen), who have never used tobacco/cigarettes and have the capacity to give informed consent.
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Procedure: Bronchoscopy
Passage of a thin flexible tube through the mouth, into the windpipe and then into the bronchial tubes so that the study doctor can look into the lungs to perform Bronchoalveolar lavage (BAL), cytologic brushing, and protected specimen brushing. Radiation: Chest X-ray To identify any previously undiagnosed lung disease that will either increase the risk of bronchoscopy or confound results of the study.
Other Name: CXR Procedure: Venipuncture To collect blood cells and serum for analyses.
Other Name: Blood Test Procedure: Intravenous Catheter To administer the appropriate medications for the bronchoscopy procedure.
Other Name: IV |
Cannabis Smokers
The exposed cohort will have daily or near daily cannabis smoking histories equivalent to a minimum of 20 joint years (number of joints smoked per day multiplied by years of cannabis smoking), will not have a significant tobacco/cigarette smoking history and will be able to provide informed consent.
|
Procedure: Bronchoscopy
Passage of a thin flexible tube through the mouth, into the windpipe and then into the bronchial tubes so that the study doctor can look into the lungs to perform Bronchoalveolar lavage (BAL), cytologic brushing, and protected specimen brushing. Radiation: Chest X-ray To identify any previously undiagnosed lung disease that will either increase the risk of bronchoscopy or confound results of the study.
Other Name: CXR Procedure: Venipuncture To collect blood cells and serum for analyses.
Other Name: Blood Test Procedure: Intravenous Catheter To administer the appropriate medications for the bronchoscopy procedure.
Other Name: IV |
- Change in alveolar macrophage phagocytosis related to the use of cannabis [ Time Frame: Baseline and at 18 hours ]Alveolar macrophage phagocytosis, secretion of pro-inflammatory cytokines, and cellular apoptosis, both at baseline, and after stimulation with pathogen-associated molecular patterns.
- Evaluation of intrapulmonary oxidative stress indices in bronchalveolar lavage (BAL) [ Time Frame: Baseline ]Intrapulmonary oxidative stress indices will be measured in both isolated alveolar macrophages (AM) and acellular epithelial lining fluid derived from bronchoalveolar lavage (BAL).
- Assessment of Lung Function [ Time Frame: Baseline ]Spirometry/Pulmonary function testing
Biospecimen Retention: Samples With DNA
- Urine
- Exhaled Breath Condensate
- Blood/Plasma
- Bronchial brushings
- Bronchoalveolar Lavage
- Oral rinse

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Ages Eligible for Study: | 18 Years to 55 Years (Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Sampling Method: | Non-Probability Sample |
Inclusion Criteria:
INCLUSION CRITERIA for CANNABIS USING patient: Subjects will be eligible if they meet ALL of the following criteria:
- Daily or near daily cannabis use (inhaled via joint/cigarette or pipe) equivalent to AT LEAST 20 "joint years" (number of joints/cigarettes per day multiplied by number of years during which cannabis was smoked) by self-report and validated through urine drug screen.
- Never or limited exposure to inhaled tobacco products (equivalent to LESS THAN one "pack year" in a lifetime) by selfreport and validated through negative urine cotinine screen.
- Capacity to answer screening questions and provide informed consent at time of interview, along with contact information
INCLUSION CRITERIA for CONTROL patient: Subjects will be eligible if they meet all of the following:
- No cannabis use ever by self-report, and validated through urine drug screen.
- Never users of tobacco/cigarettes
- Capacity to answer screening questions and provide informed consent at time of interview, along with contact information.
Exclusion Criteria:
EXCLUSION CRITERIA for CANNABIS USING patient: Subjects will be ineligible if they meet ANY of the following criteria:
- LESS THAN near daily cannabis use (inhaled via joint/cigarette or pipe) equivalent to LESS THAN 20 "joint years" (number of joints/cigarettes per day multiplied by number of years during which cannabis was smoked) or a negative urine drug screen (for cannabis)
- Inhaled tobacco product exposure EXCEEDING one "pack year" or a positive urine cotinine screen
- Elevated AUDIT-C score: A 3 item questionnaire to identify subjects with alcohol use disorders.
- Prior medical history of liver disease: cirrhosis, total bilirubin > 2.0 mg/dL or albumin <3
- Prior medical history of myocardial infarction or congestive heart failure
- Prior medical history of end-stage renal disease or serum creatinine >3 mg/dL
- Prior history of or current use of illicit drug use defined as a positive toxicology screen for opiates or cocaine
- Prior history of diabetes mellitus
- Prior history of chronic obstructive pulmonary disease (COPD) or asthma that is not clinically controlled (have not required systemic corticosteroids in the past month)
- Prior history of HIV, not controlled or on medication
- Peripheral white blood cell count of less than 3000
- Acute worsening (<7 days) in respiratory symptoms (such as change in cough frequency or sputum production, fever, dyspnea, abnormal chest radiograph), or room air pulse oximetry of < 92% at rest or spirometry of < 50% predicted for FEV1 and FVC
- Use of systemic antibiotics for any reason in the past month (4 weeks)
- Failure of a subject or the subject's substance abuse counselor to provide assent
- Nutritional risk index of less than 95
- Age < 21 or > 55 (using an age of 55 limits the likelihood of comorbid conditions that may increase the risk of adverse events with bronchoscopy)
- Pregnancy
- Decisionally challenged
- Prisoners.
EXCLUSION CRITERIA for CONTROL patient: Subjects will be ineligible to participate if they meet ANY of the following criteria:
- History of inhaled cannabis exposure EXCEEDING one "joint year" or positive urine toxicology screen (for cannabis)
- History of inhaled tobacco product exposure EXCEEDING one "pack year" or a positive urine cotinine screen
- Elevated AUDIT-C score: A 3 item questionnaire to identify subjects with alcohol use disorders.
- Prior medical history of liver disease: cirrhosis, total bilirubin > 2.0 mg/dL or albumin <3
- Prior medical history of myocardial infarction or congestive heart failure
- Prior medical history of end-stage renal disease or serum creatinine >3 mg/dL
- Prior history of or current use of illicit drug use defined as a positive toxicology screen for opiates or cocaine
- Prior history of diabetes mellitus
- Prior history of chronic obstructive pulmonary disease (COPD) or asthma that is not clinically controlled (have not required systemic corticosteroids in the past month)
- Prior history of HIV, not controlled or on medication
- Peripheral white blood cell count of less than 3000
- Acute worsening (<7 days) in respiratory symptoms (such as change in cough frequency or sputum production, fever, dyspnea, abnormal chest radiograph), or room air pulse oximetry of < 92% at rest or spirometry of < 50% predicted for FEV1 and FVC
- Use of systemic antibiotics in the past month (4 weeks)
- Failure of a subject or the subject's substance abuse counselor to provide assent
- Nutritional risk index of less than 95
- Age < 21 or > 55
- Pregnancy
- Decisionally challenged
- Prisoners.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02480283
Contact: Jeffrey D McKeehan, MSN | 303-724-6080 | jeffrey.mckeehan@ucdenver.edu | |
Contact: Ellen L Burnham, MD | 303-724-6078 | ellen.burnham@ucdenver.edu |
United States, Colorado | |
University of Colorado, Denver | Recruiting |
Aurora, Colorado, United States, 80045 |
Principal Investigator: | Ellen L Burnham, MD | University of Colorado, Denver |
Responsible Party: | University of Colorado, Denver |
ClinicalTrials.gov Identifier: | NCT02480283 |
Other Study ID Numbers: |
14-1957 UL1TR001082 ( U.S. NIH Grant/Contract ) |
First Posted: | June 24, 2015 Key Record Dates |
Last Update Posted: | June 21, 2021 |
Last Verified: | June 2021 |
Marijuana Abuse Substance-Related Disorders Chemically-Induced Disorders Mental Disorders |