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Impact of Reduced Cannabis Use on Functional Outcomes

Impact of Reduced Cannabis Use on Functional Outcomes

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03681353
Enrollment
25
Registered
2018-09-24
Start date
2019-04-04
Completion date
2020-09-23
Last updated
2021-03-05

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

Conditions

Cannabis, Cannabis Use

Brief summary

Nearly 20 million Americans report use of cannabis in the past month, and heavy cannabis use has increased by nearly 60% in the U.S. since 2007. Heavy cannabis use is associated with lower educational attainment, reduced physical activity, and increased rates of addiction, unemployment, and neuropsychological deficits. Studies by the lab and others suggest that cannabis use is also associated with increased mental health symptoms and suicidal and nonsuicidal self-injury. In addition, cannabis is the illicit drug most strongly associated with drugged driving and traffic accidents, including fatal accidents. There is evidence that sustained abstinence from cannabis can lead to improvements in the functional outcomes of former users. However, he degree to which reductions in cannabis use might be associated with positive changes in functional outcomes is currently unknown. The overall objective of the present research is to use ecological momentary assessment (EMA), a real-time, naturalistic data collection method, to study the impact of reduced cannabis use on functional outcomes in heavy cannabis users. Contingency management (CM) will be used to promote reductions in frequency and quantity of cannabis use. CM is an intensive behavioral therapy that is highly effective at producing short-term reductions in illicit drug use. The investigators novel approach includes mobile technology to make CM more portable and feasible. The present research will use this technology in conjunction with state-of-the-art EMA methods to study the impact of reduced cannabis use on key functional outcomes. The investigators central hypothesis is that reductions in frequency and quantity of cannabis use will lead to positive changes in cannabis users' mental health, physical activity, working memory, health-related quality of life, and driving behavior.

Detailed description

Nearly 20 million Americans report use of cannabis in the past month, and heavy cannabis use has increased by nearly 60% in the U.S. since 2007. Heavy cannabis use is associated with lower educational attainment, reduced physical activity, and increased rates of addiction, unemployment, and neuropsychological deficits. Studies by the lab and others suggest that cannabis use is also associated with increased mental health symptoms and suicidal and nonsuicidal self-injury. In addition, cannabis is the illicit drug most strongly associated with drugged driving and traffic accidents, including fatal accidents. While there is evidence that sustained abstinence can lead to improvements in the functional outcomes of former users, the degree to which reductions in cannabis use alone (i.e., in the absence of sustained abstinence) might be associated with positive changes in functional outcomes is currently unknown. This is a critical gap in the literature, as many clinical interventions for cannabis and other drugs are associated with decreases in frequency and quantity of use, but fail to achieve an effect on overall abstinence rates. The overall objective of the present research is to use ecological momentary assessment (EMA), a real-time, naturalistic data collection method, to prospectively study the impact of reduced cannabis use on functional outcomes in heavy cannabis users. EMA addresses several limitations of traditional assessment techniques by enhancing ecological validity, minimizing memory bias, and enabling examination of the impact of context on participants' behavior. Contingency management (CM) will be used to promote reductions in frequency and quantity of cannabis use. CM is an intensive behavioral therapy that is highly effective at producing short-term reductions in illicit drug use. Moreover, the investigators have recently developed a novel approach that leverages mobile technology and recent developments in cannabis testing to make CM for cannabis more portable and feasible. The investigators have pilot-tested this approach with heavy cannabis users and found that it is an acceptable and feasible method to reduce their cannabis use. The present research will use this technology in conjunction with state-of-the-art EMA methods to study the impact of reduced cannabis use on key functional outcomes. The investigators central hypothesis is that reductions in frequency and quantity of cannabis use will lead to positive changes in cannabis users' mental health, physical activity, working memory, health-related quality of life, and driving behavior. The rationale for this research is that it will provide the first and only real-time data concerning the potential impact of reductions in cannabis use on functional outcomes. As such, the findings from the present research will directly inform ongoing efforts to include reductions in illicit drug use as a valid, clinically-meaningful outcome measure in clinical trials of pharmacotherapies for the treatment of substance use disorders.

Interventions

BEHAVIORALMobile Contingency Management, active

Participants are provided monetary reinforcement for providing oral fluid test results that suggest they have reduced cannabis use.

Sponsors

Duke University
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No

Inclusion criteria

* cannabis use on ≥40 of past 90 days * ability to speak and write fluent English * 18-70 years of age * willingness to attempt to temporarily reduce cannabis use

Exclusion criteria

* expect to have an unstable medication regimen during the study * are currently receiving non-study CUD treatment * meet criteria for serious mental illness (e.g., bipolar disorder, schizophrenia) * become imprisoned * become hospitalized for psychiatric reasons * become pregnant * report imminent risk for suicide or homicide * meet criteria for a substance use disorder other than CUD or tobacco

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants Who Complete the Baseline AssessmentBaselineAdherence is defined as completing the baseline assessment
Number of Participants Who Complete the 8-week Follow-up Assessment8- week follow upAdherence is defined as completing the 8-week follow-up assessment
Number of Participants Who Complete 1 or More Ecological Momentary Assessments (EMA) Per Day (Total ≥56) for the Duration of the 8-week EMA Protocol8 week follow upAdherence is defined as completing 1 or more EMA assessments per day (total ≥56) for the duration of the 8-week EMA protocol
Number of Participants Who Score Above Threshold on Treatment Acceptability Measure8-week posttreatment visitAcceptability of treatment will be measured by a questionnaire designed for use in this study. A single item measured acceptability of treatment, with a Likert scale (1-10) response in which 1=extremely unacceptable and 10=extremely acceptable. Threshold for acceptability is a score of 6 or greater.

Secondary

MeasureTime frameDescription
Average Number of Days Since Last Cannabis Use8-week posttreatment visitInvestigators will use count-adjusted (i.e., negative binomial or Poisson) MLM to model the equivalent number of joints/gram smoked on a given day as a function of days since last use.
Number of Participants Who Have ≥ 50% Reduction in Quantity of Cannabis UseAd lib monitoring period (up to 2 weeks), 8-week posttreatment visitTo evaluate if this milestone has been met, the investigators will calculate the percentage reduction in overall cannabis quantity by comparing the ad lib monitoring period to the mobile CM period.
Number of Participants Who Have ≥ 50% Reduction in Frequency of Cannabis UseAd lib monitoring period (up to 2 weeks), 8-week posttreatment visitTo evaluate if this milestone has been met, the investigators will calculate the percentage reduction in bioverified abstinent days by comparing the ad lib monitoring period to the mobile CM period.

Countries

United States

Participant flow

Participants by arm

ArmCount
Reduced Use Condition
This arm includes six weeks of mobile contingency management treatment administered via a smart-phone based application (mobile CM), in which participants are provided monetary reinforcement for reducing cannabis use. Mobile Contingency Management, active: Participants are provided monetary reinforcement for providing oral fluid test results that suggest they have reduced cannabis use.
18
Total18

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyLost to Follow-up2
Overall StudyWithdrawal by Subject3
Overall Studywithdrawn by PI2

Baseline characteristics

CharacteristicReduced Use Condition
Age, Continuous36.95 years
STANDARD_DEVIATION 12.93
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
17 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
11 Participants
Race (NIH/OMB)
More than one race
1 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
Race (NIH/OMB)
White
5 Participants
Region of Enrollment
United States
18 Participants
Sex: Female, Male
Female
8 Participants
Sex: Female, Male
Male
10 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 18
other
Total, other adverse events
2 / 18
serious
Total, serious adverse events
1 / 18

Outcome results

Primary

Number of Participants Who Complete 1 or More Ecological Momentary Assessments (EMA) Per Day (Total ≥56) for the Duration of the 8-week EMA Protocol

Adherence is defined as completing 1 or more EMA assessments per day (total ≥56) for the duration of the 8-week EMA protocol

Time frame: 8 week follow up

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Complete 1 or More Ecological Momentary Assessments (EMA) Per Day (Total ≥56) for the Duration of the 8-week EMA Protocol8 Participants
Primary

Number of Participants Who Complete the 8-week Follow-up Assessment

Adherence is defined as completing the 8-week follow-up assessment

Time frame: 8- week follow up

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Complete the 8-week Follow-up Assessment18 Participants
Primary

Number of Participants Who Complete the Baseline Assessment

Adherence is defined as completing the baseline assessment

Time frame: Baseline

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Complete the Baseline Assessment18 Participants
Primary

Number of Participants Who Score Above Threshold on Treatment Acceptability Measure

Acceptability of treatment will be measured by a questionnaire designed for use in this study. A single item measured acceptability of treatment, with a Likert scale (1-10) response in which 1=extremely unacceptable and 10=extremely acceptable. Threshold for acceptability is a score of 6 or greater.

Time frame: 8-week posttreatment visit

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Score Above Threshold on Treatment Acceptability Measure18 Participants
Secondary

Average Number of Days Since Last Cannabis Use

Investigators will use count-adjusted (i.e., negative binomial or Poisson) MLM to model the equivalent number of joints/gram smoked on a given day as a function of days since last use.

Time frame: 8-week posttreatment visit

ArmMeasureValue (MEAN)Dispersion
Reduced Use ConditionAverage Number of Days Since Last Cannabis Use6.95 daysStandard Deviation 9.55
Secondary

Number of Participants Who Have ≥ 50% Reduction in Frequency of Cannabis Use

To evaluate if this milestone has been met, the investigators will calculate the percentage reduction in bioverified abstinent days by comparing the ad lib monitoring period to the mobile CM period.

Time frame: Ad lib monitoring period (up to 2 weeks), 8-week posttreatment visit

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Have ≥ 50% Reduction in Frequency of Cannabis Use12 Participants
Secondary

Number of Participants Who Have ≥ 50% Reduction in Quantity of Cannabis Use

To evaluate if this milestone has been met, the investigators will calculate the percentage reduction in overall cannabis quantity by comparing the ad lib monitoring period to the mobile CM period.

Time frame: Ad lib monitoring period (up to 2 weeks), 8-week posttreatment visit

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Reduced Use ConditionNumber of Participants Who Have ≥ 50% Reduction in Quantity of Cannabis Use18 Participants

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