Viimeisen kahdenkymmenen vuoden aikana Tanskassa on kannabiksen ja skitsofrenian yhteys kasvanut 3-4 -kertaiseksi

Viimeisen kahdenkymmenen vuoden aikana Tanskassa on kannabiksen ja skitsofrenian yhteys kasvanut 3-4 -kertaiseksi
Kannabiksen laillistaminen ei ole järkevää.

kts artikkelin tiivistelmä alla.
Development Over Time of the Population-Attributable Risk Fraction
for Cannabis Use Disorder in Schizophrenia in Denmark
Carsten Hjorth.j, PhD; Christine Merrild Posselt, MSc; Merete Nordentoft, DrMedSc
IMPORTANCE Cannabis use and potency of cannabis have increased during the past 2
decades. If the association between cannabis use and schizophrenia is causal, this should be
reflected in an increase in the proportion of cases of schizophrenia being attributable to
cannabis, the population-attributable risk fraction (PARF).
OBJECTIVE To determine whether the PARF for cannabis use disorder in schizophrenia has
increased over time.
DESIGN, SETTING, AND PARTICIPANTS This nationwide, register-based historical prospective
cohort study included all people in Denmark born before December 31, 2000, who were alive
and 16 years or older at some point from January 1, 1972, to December 31, 2016. Data analysis
was performed from August 2020 to April 2021.
EXPOSURE Diagnosis of cannabis use disorder.
MAIN OUTCOMES AND MEASURES Diagnosis of schizophrenia, with estimated PARF
of cannabis use disorder in schizophrenia from 1972 to 2016.
RESULTS A total of 7 186 834 individuals were included in the analysis, including 3 595 910
women (50.0%) and 3 590 924 men (50.0%). The adjusted hazard ratio for schizophrenia
fluctuated at approximately 4 (with 95%CIs ranging from approximately 3 to 6) throughout
most of the study period when people diagnosed with cannabis use disorder were compared
with those without cannabis use disorder. The PARF of cannabis use disorder in schizophrenia
also fluctuated, but with clear evidence of an increase from 1995 (when the PARF was
relatively stable around 2.0%, with a 95%CI of approximately 0.3%to either side) until
reaching some stability around 6.0% to 8.0% (with a 95%CI of approximately 0.5%
to either side) since 2010.
CONCLUSIONS AND RELEVANCE The results from these longitudinal analyses show the
proportion of cases of schizophrenia associated with cannabis use disorder has increased
3- to 4-fold during the past 2 decades, which is expected given previously described increases
in the use and potency of cannabis. This finding has important ramifications regarding
legalization and control of use of cannabis.
JAMA Psychiatry. doi:10.1001/jamapsychiatry.2021.1471
Published online July 21, 2021.