Understanding Cannabis Use Disorder

The American Psychiatry Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-5) defines Cannabis Use Disorder as: a problematic pattern of cannabis use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period:

1. Cannabis is often taken in larger amounts over a longer period than was intended;
2. There is a persistent desire or unsuccessful efforts to cut down or control cannabis use;
3. A great deal of time is spent in activities necessary to obtain cannabis, use cannabis, or recover from its effects;
4. Craving, or strong desire or urge to use cannabis;
5. Recurrent cannabis use resulting in a failure to fulfill major role obligations at work, school or home;
6. Continued cannabis use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of cannabis;
7. Important social, occupational, or recreational activities are given up or reduced because of cannabis use;
8. Recurrent cannabis use in situations in which it is physically dangerous;
9. Cannabis use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by cannabis;
10. Tolerance, as defined by either of the following:
    1. A need for markedly increased amounts of cannabis to achieve intoxication or desired effect;
    2. A markedly diminished effect with continued use of the same amount of cannabis.
11. Withdrawal, as manifested by either of the following:
    1. The characteristic withdrawal syndrome for cannabis as defined by DSM-5, or
    2. Cannabis, or a closely related substance, is taken to relieve or avoid withdrawal symptoms.

The DSM-5 defines cannabis withdrawal as the presence of three or more of the following signs and symptoms developed within approximately one week after cessation of heavy, prolonged use:

1. Irritability, anger or aggression
2. Nervousness or anxiety
3. Sleep difficulty (insomnia, disturbing dreams)
4. Decreased appetite or weight loss
5. Restlessness
6. Depressed mood
7. At least one of the following physical symptoms causing significant discomfort: abdominal pain, shakiness/tremors, sweating, fever, chills, or headache

An individual exhibiting two to three of the symptoms experiences mild CUD, while presence of four to five of the symptoms relate to moderate CUD. Severe CUD results when the person experiences six or more of the symptoms.

Despite its widespread usage, the American Society of Addiction Medicine acknowledges that cannabis consumption results in distinct effects on the brain and behavior and CUD represents a significant health problem. Numerous research studies confirm that an association exists between cannabis use and adverse social and health outcomes, including impaired neurocognitive function, poor memory, prenatal cannabis-associated early childhood effects, and psychosis and suicidality among teens and young adults. CUD, though, is associated with a broad range health-related concerns, including cognitive decline, respiratory and cardiovascular disease, and psychiatric symptoms. Proceeding from use to CUD results in more serious physical and psychological effects than occasional use. CUD presents differently in men and women, particularly in symptoms of cannabis withdrawal, with women reporting a greater increase in withdrawal symptoms during periods of abstinence than men. Additionally, tobacco and cannabis smoke share many known carcinogenic chemical compounds, associating cannabis smoking with an increased risk of head, neck and respiratory cancers.

Cannabis use during pregnancy presents unique concerns for fetal health. Women use cannabis more frequently during pregnancy than any other federally regulated drug. A recent study revealed a prevalence of cannabis use disorders among pregnant females, with a rate as high as 26.1%. Research links prenatal exposure to cannabis to adverse birth consequences, including small size for gestational age, neonatal intensive care unit admissions, and preterm birth, as well as childhood outcomes such as autism spectrum disorder, attention-deficit/hyperactivity disorder, as well as symptoms of psychopathology.

Co-occurring mental health disorders prevail among individuals diagnosed with CUD. Cannabis-induced mental health diagnoses include anxiety disorders, depression, psychotic and nonpsychotic bipolar disorder, schizophrenia, amotivational syndrome, disruptive cognitive function, neuropsychological decline and psychotic disorders. Various clinical and epidemiological studies reveal that 12% of persons treated for or diagnosed with major depressive disorder also experience CUD, while 24% of those with bipolar disorder use cannabis and 20% experience CUD. Among patients with schizophrenia, 26.6% exhibit current CUD or meet the criteria for life-time CUD.

Cannabis potency causes an additional concern for abusers. Marijuana available between the 1960s and the early 1980s yielded a THC content of about 2%. Cultivation techniques result in the current availability of products with increasingly higher THC levels. Studies suggest a two to three fold increase in THC levels in both illicit markets and U.S. state-legalized markets over the past four decades, rising from THC levels of 4% in the mid 1980’s to up to 72% in some THC concentrate samples today, Other cannabis products such as oil, shatter, dab and edibles offer a THC potency of up to 95%. Research studies link high-potency cannabis with a greater risk of long-term brain changes, psychosis and addiction, as compared with use of low-THC level products.

Proponents of cannabis legalization often cite a “medicinal” justification for marijuana use and increased potency of products. At the federal level, cannabis remains a Schedule I drug, meaning it offers no accepted medical purposes. Despite widespread promotion of cannabis as a therapeutic agent, “medicinal use” most often fails to result in any therapeutic benefit. Even as a Schedule I drug, though, in the U.S., four cannabis products have received limited federal approval for medicinal use, garnering approval to address chemotherapy-associated nausea and vomiting, to stimulate appetite in patients with HIV, to treat two rare forms of seizures and (although not in the U.S.) address multiple sclerosis-associated spasticity and neuropathic pain. No research studies support high levels of THC as beneficial for any medical condition, but rather the development of high-potency products operate for the purpose of producing psychoeffective results – in other words, a greater “high.”

A recent meta-analysis of epidemiological studies on the prevalence risk of CUD found that about 22% of individuals who use cannabis experience CUD, and the rate of not only cannabis use but CUD has increased, and is anticipated to continue to rise, paralleling the changes in the legal status of marijuana. Treatment for CUD generally involves psychotherapeutic intervention, focusing on the utilization of cognitive-behavioral therapy, motivational enhancement therapy, and contingency management, although the evidence suggests that a combination of the three treatment modalities produces the best outcomes. There are no current FDA-approved pharmacological treatments for CUD.

With more and more states legalize the use of cannabis for non-medical purposes, in other words, recreational use, we can anticipate additional research findings into the prevalence of cannabis use and CUD, and the attendant consequences for personal health and public safety.