Cannabinoid-related psychiatric hospitalizations increased nearly 5-fold in Germany over 18 years
Hospital admissions for cannabinoid-related mental disorders in Germany increased 4.8-fold between 2000 and 2018, with significant rises across intoxication, dependence, withdrawal, and psychotic disorders.
Quick Facts
What This Study Found
All categories of cannabinoid-related psychiatric hospitalizations increased significantly: intoxications, harmful use, dependence syndrome, withdrawal, psychotic disorders, and residual/late-onset psychotic disorders. The overall relative frequency increased 4.8-fold comparing 2000 and 2018. Meanwhile, alcohol dependence admissions remained stable and schizophrenia-spectrum admissions slightly decreased.
Key Numbers
4.8-fold increase in relative frequency from 2000 to 2018. All six subcategories showed statistically significant increases (p<0.001 for most). Schizophrenia admissions slightly decreased (p=0.008). Alcohol dependence unchanged (p=0.844).
How They Did This
Analysis of all inpatient hospital diagnoses in Germany from 2000-2018 using Federal Statistical Office (Destatis) data. Linear trend analysis of absolute and relative annual frequencies of ICD-10 cannabinoid-related diagnoses versus control diagnoses.
Why This Research Matters
The dramatic increase in cannabinoid-related psychiatric hospitalizations coincides with rising recreational use, synthetic cannabinoid availability, and increasing THC content in cannabis preparations.
The Bigger Picture
The divergence between increasing cannabinoid-related admissions and stable/decreasing alcohol and schizophrenia admissions suggests a specific cannabis-related public health trend rather than a general increase in psychiatric hospitalizations.
What This Study Doesn't Tell Us
Administrative data may reflect changes in diagnostic practices, awareness, or healthcare-seeking behavior rather than true incidence changes. Cannot link to individual-level cannabis use data.
Questions This Raises
- ?How much of the increase is driven by synthetic cannabinoids versus natural cannabis?
- ?Are rising THC concentrations a major contributing factor?
Trust & Context
- Key Stat:
- 4.8-fold increase in cannabinoid-related psychiatric hospitalizations (2000-2018)
- Evidence Grade:
- Complete national hospital data providing a reliable trend, though administrative data cannot determine causation.
- Study Age:
- Published in 2022 with German hospital data from 2000-2018.
- Original Title:
- Incidence of inpatient cases with mental disorders due to use of cannabinoids in Germany: a nationwide evaluation.
- Published In:
- European journal of public health, 32(2), 239-245 (2022)
- Authors:
- Gahr, Maximilian, Ziller, Julia, Keller, Ferdinand, Muche, Rainer, Preuss, Ulrich W, Schönfeldt-Lecuona, Carlos
- Database ID:
- RTHC-03856
Evidence Hierarchy
Looks back at existing records to find patterns.
What do these levels mean? →Frequently Asked Questions
Which types of cannabis-related mental disorders increased most?
All categories showed significant increases, including intoxication, harmful use, dependence, withdrawal, psychotic disorders, and residual/late-onset psychotic disorders.
Could this just reflect more people seeking help?
Partially possible, but the contrast with stable alcohol dependence admissions and slightly declining schizophrenia admissions over the same period suggests a real increase in cannabinoid-related psychiatric problems specifically.
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Cite This Study
https://rethinkthc.com/research/RTHC-03856APA
Gahr, Maximilian; Ziller, Julia; Keller, Ferdinand; Muche, Rainer; Preuss, Ulrich W; Schönfeldt-Lecuona, Carlos. (2022). Incidence of inpatient cases with mental disorders due to use of cannabinoids in Germany: a nationwide evaluation.. European journal of public health, 32(2), 239-245. https://doi.org/10.1093/eurpub/ckab207
MLA
Gahr, Maximilian, et al. "Incidence of inpatient cases with mental disorders due to use of cannabinoids in Germany: a nationwide evaluation.." European journal of public health, 2022. https://doi.org/10.1093/eurpub/ckab207
RethinkTHC
RethinkTHC Research Database. "Incidence of inpatient cases with mental disorders due to us..." RTHC-03856. Retrieved from https://rethinkthc.com/research/gahr-2022-incidence-of-inpatient-cases
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.