Cannabis Use Disorder, Moderate, Cannabis Use Disorder, Severe
Conditions
Brief summary
Heavy cannabis use is associated with substantive learning and memory impairments and elevated risk of psychopathology. It has been repeatedly demonstrated that the hippocampus, centrally implicated in these processes, is particularly vulnerable to the deleterious effects of prolonged exposure to cannabis. This deterioration of hippocampal structure, function, and biochemistry can be reversed, but this requires two or more years of abstinence from cannabis. However, most heavy cannabis users find it extremely difficult to maintain abstinence over extended periods and current treatments for cannabis use disorders are inadequate. There is a pressing clinical need for an intervention that rapidly accelerates hippocampal recovery, ameliorates the associated cognitive impairments and mental health symptoms, and leads to improved treatment outcomes. One promising candidate is physical exercise. In addition to the well-known physical health benefits, regular exercise also has a potent positive effect on brain health. The current study will investitive the capacity of two different neuroscientifically-informed 12-week exercise programs can restore brain health for heavy long term cannabis users.
Detailed description
Heavy cannabis use is associated with substantive learning and memory impairments and elevated risk of psychopathology. It has been repeatedly demonstrated that the hippocampus, centrally implicated in these processes, is particularly vulnerable to the deleterious effects of prolonged exposure to cannabis. This deterioration of hippocampal structure, function, and biochemistry can be reversed, but this requires two or more years of abstinence from cannabis. However, most heavy cannabis users find it extremely difficult to maintain abstinence over extended periods and current treatments for cannabis use disorders are inadequate. There is a pressing clinical need for an intervention that rapidly accelerates hippocampal recovery, ameliorates the associated cognitive impairments and mental health symptoms, and leads to improved treatment outcomes. One promising candidate is physical exercise. In addition to the well-known physical health benefits, regular exercise also has a potent positive effect on brain health and can increase the size of the hippocampus. It's not yet known how much or what kind of exercise produces the best results. This study has been designed to compare the effects of two different exercise programs. 1. 12 weeks of regular HIIT exercise 2. 12 weeks of regular strength training The research team are investigating whether the programs have a positive impact on brain health and, if they do, whether one is more effective than the other. The research team will also measure whether engaging in either program leads to a reduction in cannabis consumption, and improvements in thinking skills, mental health, and general wellbeing.
Interventions
BEHAVIORALHigh Intensity Interval Training
Exercise sessions will commence with an initial 3-week accustomization period whereby training load will increase incrementally from 2 x 45min sessions with effort peaking at 60% VO2 max (week 1) increasing to 3 x 45minute with effort peaking at 80% VO2max (week 3). Participants will transition to the full HIIT protocol for the remaining weeks. The HIIT component will comprise a work-rest ratio of ≥1:1minutes, with alternating exertion epochs at \>80% VO2max and \<60% VO2max. As VO2max is likely to increase as fitness improves toward the end of the 3-month program, adjustments to HIIT will be made by the exercise physiologist based on real-time heart rate monitoring, ensuring greater accuracy in participants achieving their heart rate targets.
BEHAVIORALStrength and Resistance Training
Exercise sessions will comprise a combination of strength, coordination and mobility exercises. The strength component will consist of 2-3 sets of resistance exercises at ≤70% of a predicted 1 repetition maximum, targeting all body segments. Heart rate tracking will occur to ensure participants do not exceed 70% v02 (or exceed Lactate Threshold).
Sponsors
Turning Point
Monash University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
20 Years to 55 Years
Healthy volunteers
No
Inclusion criteria
1. Aged 20-55 years 2. Voluntary and able to provide informed consent 3. Fluent in English 4. Current moderate - severe cannabis use disorder 5. Major history of cannabis use (i.e. ≥3 days per week on average for ≥4 of the past 6 years) 6. Capacity to tolerate physical exercise according to 'Fitness to Exercise'
Exclusion criteria
1. Have a history of cardiovascular disease, high blood pressure, musculoskeletal injury or other condition that would preclude safe engagement in VO2 max fitness testing and/or regular physical exercise 2. Severe claustrophobia, non-MR compatible metallic implant, or other contraindication to MRI scanning 3. Lifetime history of significant neurological illness, or moderate - severe brain injury, 4. Current major unstable medical illness or chronic pain condition 5. Lifetime history of schizophrenia, schizoaffective disorder, OCD, PTSD, bipolar disorder 6. Current significant depression or anxiety that precludes ability to reliably engage in the exercise program 7. Current moderate - severe substance use disorder for substances other than cannabis (excluding nicotine) 8. Currently pregnant or lactating 9. Shift work employment schedule within the prior 6-months 10. Have engaged in ≥5 sessions of HITT or resistance training within the past 12-months 11. History of treatment with antipsychotic medications 12. Current participation in psychosocial treatment for substance use disorder 13. Other psychoactive medications or psychosocial treatments will be considered on a case-by-case basis. Where a current psychoactive medication is deemed acceptable, both dose and type must have been stable for a minimum of four weeks prior to baseline assessment, and remain stable throughout the 12-week exercise phase of the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in hippocampal integrity | Baseline (0 months), post (3 months) | Composite score derived from three hippocampal health indices: volume (structural MRI), connectivity (DTI), neuronal health (MRS NAA) calculated as described in Yucel et al (2016), doi:10.1038/tp.2015.201. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in cannabis use | Baseline (0 months), post (3 months), follow up (6 months) | Time line follow back |
| Change in cannabis dependence | Baseline (0 months), post (3 months), follow up (6 months) | Severity of Dependence Scale (SDS; range = 0-15 higher scores indicate higher dependence |
| Change in cannabis craving | Baseline (0 months), post (3 months), follow up (6 months) | Penn Craving Scale (PCS; range = 0 - 30 higher scores indicate greater craving) |
| Change in depression symptoms | Baseline (0 months), post (3 months), follow up (6 months) | Quick Inventory of Depressive Symptomology (QUIDS; range = 0 - 27 higher scores indicate greater depression symptom severity) |
| Change in anxiety symptoms | Baseline (0 months), post (3 months), follow up (6 months) | StateTrait Anxiety Inventory (STAI; range = 20 to 80, higher scores indicate greater anxiety) |
| Change in resilience | Baseline (0 months), post (3 months), follow up (6 months) | Connor David Resilience Scale (CDRS; range = 0-100 higher scores indicate higher resilience) |
| Change in mental wellbeing | Baseline (0 months), post (3 months), follow up (6 months) | Warwick Edinburgh Mental Wellbeing Scale (WEMWBS; range = 14-70 higher scores indicate increased mental well being) |
| Change in sleep quality | Baseline (0 months), post (3 months), follow up (6 months) | Pittsburgh Sleep Quality Index (PSQI; range = 0 to 21 higher scores indicate worse sleep quality) |
| Change in quality of life | Baseline (0 months), post (3 months), follow up (6 months) | Quality of Life and Satisfaction Questionnaire - Short Form (QOL-SF; range = 70 higher scores indicate greater life satisfaction and enjoyment) |
| Change in memory | Baseline (0 months), post (3 months), follow up (6 months) | Rey Auditory Verbal Learning Test (RAVLT) |
| Change in associative memory | Baseline (0 months), post (3 months), follow up (6 months) | Paired Associates Learning Task (PAL) |
| Change in visual memory | Baseline (0 months), post (3 months) | Figural Memory Tasks |
| Change in cardiorespiratory fitness | Baseline (0 months), post (3 months) | VO2 max |
| Change in coping skills | Baseline (0 months), post (3 months), follow up (6 months) | Perceived Stress Scale (10 item; range = 0 - 40 higher scores indicate greater stress) |
Countries
Australia
Outcome results
None listed