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Sekä skitsofreniaan nuorena sairastuneilla että kannabiksen käyttäjillä on todettu vasemman päälaenlohkon volyymivähentymistä

Parietal Lobe Volume Deficits in

Adolescents With Schizophrenia and

Adolescents With Cannabis Use Disorders

Sanjiv Kumra,et al

Varhain alkavassa skitsofreniassa on todettu parietaali- eli päänlaenlohkon epänormaaliuksia. Kannabis on tunnettu skitsofrenian puhkeamisen aikaistaja. Sekä skitsofreniaan nuorena sairastuneilla että kannabiksen käyttäjillä on todettu vasemman päälaenlohkon volyymivähentymistä. Jos oli sekä skitsofrenia että kannabiksen käyttö, niin myös vasen talamus oli pienempi kuin verrokkiryhmällä.

Kannabis on siis nuoren aivojen kehitykselle haitallista.

Objective:

In early-onset schizophrenia (EOS), the earliest structural brain volumetric abnormalities appear in the parietal cortices. Early exposure to cannabis may represent an environmental risk factor for developing schizophrenia. This study characterized cerebral

cortical gray matter structure in adolescents in regions of interest (ROIs) that have been implicated in EOS and cannabis use disorders (CUD).

Method:

T1-weighted magnetic resonance images were acquired from adolescents with EOS (n 35), CUD (n16), EOS, CUD (n13), and healthy controls (HC) (n51). Using FreeSurfer, brain volume was examined within frontal, temporal, parietal and subcortical ROIs by a 2 (EOS versus no EOS) 2 (CUD versus no CUD) design using multivariate analysis of covariance. In ROIs in which

volumetric differences were identified, additional analyses of cortical thickness and surface area were conducted.

 

Results:

A significant EOS-by-CUD interaction was observed. In the left superior parietal region, both ”pure” EOS and ”pure” CUD had smaller gray matter volumes that were associated with lower surface area compared with HC. A similar alteration

was observed in the comorbid group compared with HC, but there was no additive volumetric deficit found in the comorbid group compared with the separate groups. In the left thalamus, the comorbid group had smaller gray matter volumes compared with the CUD and HC groups.

 

Conclusions:

These preliminary data indicate that the presence of a CUD may moderate the relationship between EOS and cerebral cortical gray matter structure in the left superior parietal lobe. Future research will follow this cohort over adolescence to further

examine the impact of cannabis use on neurodevelopment.

J. Am. Acad. Child Adolesc. Psychiatry, 2012;51(2):171–180.