Abstract
This study assesses survey results from adolescent marijuana users concerning mental health symptoms and marijuana use to estimate the association of acute psychotic symptoms with frequency of use.
Marijuana use is associated with acute psychotic symptoms,1 but the prevalence of these symptoms in youth is not known, to our knowledge. We surveyed adolescents presenting for routine medical care to assess whether they had experienced acute psychotic symptoms during or right after marijuana use.
Methods
We analyzed data from a survey of health and substance use that was administered to a convenience sample of youths aged 14 to 18 years presenting for routine care; 1235 patients were approached and 527 consented for a response rate of 42.7%. Youths were enrolled with a waiver of parental consent under the approval of the Boston Children’s Hospital Institutional Review Board. Measures included 2 questions about acute psychotic symptoms (“In the past 12 months, how often have you felt anxious or paranoid during or after using marijuana?” and, “In the past 12 months, how often have you seen, felt, or heard things that were not really there [ie, hallucinations] during or after using marijuana?”) and standardized questions about symptoms of cannabis use disorder (based on the modified World Mental Health Composite International Diagnostic Interview),2 anxiety (based on the 2-item Generalized Anxiety Disorder scale),3 and depression (based on the Patient Health Questionnaire 2)4 and sociodemographic characteristics. One hundred forty-six respondents who affirmed past-year marijuana use and had complete data for measures of interest were included in the analysis.
Descriptive statistics were used to characterize rates of marijuana-related psychotic symptoms by demographic variables, frequency of use, presence of cannabis use disorder, and symptoms of depression or anxiety. We used χ2 tests to compare psychotic symptoms with the sociodemographic characteristics of the sample. We used logistic regression adjusted for age, sex, and race/ethnicity to examine associations between having experienced hallucinations or paranoia related to marijuana use and screen scores for depression, anxiety, and cannabis use disorder. We used SAS version 9.4 software (SAS Institute Inc) to perform statistical analysis.
Results
Mean (SD) age of respondents was 16.6 (1.1) years; 104 (71.2%) were female; 112 (76.7%) were of non-Hispanic white race/ethnicity. Overall, 40 respondents (27.4%) reported hallucinations, 49 (33.6%) reported paranoia or anxiety, and 63 (42.9%) reported having at least 1 symptom. Neither hallucinations nor paranoia or anxiety was associated with age, sex, race/ethnicity, general health status, or socioeconomic status. Respondents who met criteria for cannabis use disorder were more likely to report having experienced hallucinations or paranoia. Seventy respondents (47.9%) affirmed “monthly or more” marijuana use during the past year, and this group was more likely to report experiencing hallucinations and paranoia compared with youths who affirmed use “once or twice” in the past year (42 [60.0%] vs 28 [40%]). Respondents with results on mental health screens that were suggestive of depression were more likely to report experiencing paranoia (23 [65.7%] vs 12 [34.3%] of 35 respondents with positive results for depression) (Table).
Table. Demographic Characteristics; Frequency of Cannabis Use; Scores on Depression, Anxiety, and Cannabis Use Disorder Screens; and Associations With Experiencing Marijuana-Related Hallucinations or Paranoia.
| Cannabis Use/Mental Health Variable | Total, No. (%) (N = 146) | Hallucinations in Past 12 mo, No. (%) | OR (95% CI)a | Paranoia or Anxiety in Past 12 mo, No. (%) | OR (95% CI)a | ||
|---|---|---|---|---|---|---|---|
| Never (n = 106) | Ever (n = 40) | Never (n = 97) | Ever (n = 49) | ||||
| Cannabis use disorder | |||||||
| CUD diagnosis | 40 (27.4) | 21 (52.5) | 19 (47.5) | 3.76 (1.69-8.34) | 19 (47.5) | 21 (52.5) | 3.15 (1.46-6.78) |
| No diagnosis | 106 (72.6) | 85 (80.2) | 21 (19.8) | 1 [Reference] | 78 (73.6) | 28 (26.4) | 1 [Reference] |
| Frequency of past-year marijuana use | |||||||
| Monthly or more | 70 (47.9) | 42 (60.0) | 28 (40.0) | 3.81 (1.71-8.50) | 37 (52.9) | 33 (47.1) | 3.30 (1.58-6.89) |
| Once or twice | 76 (52.1) | 64 (84.2) | 12 (15.8) | 1 [Reference] | 60 (78.9) | 16 (21.1) | 1 [Reference] |
| Anxiety screen | |||||||
| Positive, score ≥3 on GAD | 26 (17.8) | 16 (61.5) | 10 (38.5) | 1.84 (0.74-4.57) | 13 (50.0) | 13 (50.0) | 2.32 (0.96-5.58) |
| Negative, score <3 on GAD | 120 (82.2) | 90 (75.0) | 30 (25.0) | 1 [Reference] | 84 (70.0) | 36 (30.0) | 1 [Reference] |
| Depression screen | |||||||
| Positive, score ≥3 on PHQ | 35 (24.0) | 23 (65.7) | 12 (34.3) | 1.51 (0.66-3.45) | 15 (42.9) | 20 (57.1) | 3.75 (1.69-8.36) |
| Negative, score <3 on PHQ | 111 (76.0) | 83 (74.8) | 28 (25.2) | 1 [Reference] | 82 (73.9) | 29 (26.1) | 1 [Reference] |
Abbreviations: CUD, cannabis use disorder, determined by the modified World Mental Health Composite International Diagnostic Interview2; GAD, Generalized Anxiety Scale; OR, odds ratio; PHQ, Patient Health Questionnaire 2.
Odds ratio (95% CI) logistic regression adjusts for age (continuous), sex, and race/ethnicity.
Discussion
A sizeable proportion of adolescent marijuana users reported experiencing paranoia or anxiety or hallucinations in association with their marijuana use, with rates higher among those who used cannabis more regularly, met criteria for cannabis use disorder, or experienced symptoms of depression. Marijuana-related psychotic symptoms may become more common if rates of regular or heavy marijuana use continue to rise.5
The association between marijuana use during adolescence and poor adult outcomes has been well documented, and there is a strong association between its use and the development of mental health problems and psychotic disorders.6 Marijuana use is also associated with psychotic symptoms related to intoxication. The association between these phenomena is poorly understood. Experiencing acute psychotic symptoms while using marijuana may be a marker of risk for developing a psychotic disorder in the future. Because some adolescents with psychotic disorders report first experiencing symptoms acutely with marijuana use, these experiences may represent prodromal symptoms in some individuals. A future longitudinal study could examine these questions. A limitation of our study was self-report, which is subject to recall and social desirability biases that could lead to underreporting and hence underestimation of the true nature of the phenomenon.
The mental health burden of adolescent marijuana use may be challenging to accurately estimate because adolescents do not always seek treatment for mental health problems. Our findings suggest that experience of marijuana-related acute psychotic symptoms may be considerable.
References
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