Study register · detailQuerschnittsstudie · Multiple Sclerosis · 2011
Effects of cannabis on cognitive function in patients with multiple sclerosis.
Honarmand et al.·NeurologyImpact 1.0
HarmGRADEVery low96 citations
Samplen = 50 Pat.
ControlMS patients without cannabis use
EndpointMACFIMS
Blindingn.a.
DesignQuerschnittsstudie
Cannabinoidvollspektrum
”Key finding
Prolonged cannabis use is associated with significantly worse cognitive performance in several domains in MS patients.
Summary
n=50 MS patients (25 cannabis users vs. 25 non-users); cannabis users performed significantly worse in information processing speed, working memory, executive functions and visuospatial perception; twice as likely to be globally cognitively impaired (factor ~2,0) compared to non-users. No group differences in depression/anxiety (HADS).
P
PopulationAdults with multiple sclerosis, cannabis users (n=25) vs. non-users (n=25), total n=50
I
InterventionProlonged use of inhaled or ingested street cannabis (no controlled dosage)
C
ControlMS patients without cannabis use (n=25)
O
OutcomeCannabis users showed significantly worse performance in information processing speed, working memory, executive functions and visuospatial perception; twice as likely to be globally cognitively impaired
Confidence in the evidence
Very lowLowModerateHigh
Very low
The lowest GRADE level, the effect estimate remains uncertain.
<h4>Background</h4>While neuropsychological deficits have been reported in healthy individuals who use street cannabis, data in patients with multiple sclerosis (MS) are lacking. Given that MS is associated with cognitive deterioration, the aim of this study was to determine the neuropsychological effects of cannabis use in this population.<h4>Methods</h4>Two groups, each of 25 patients with MS (cannabis users and nonusers), were administered the Minimal Assessment of Cognitive Function in MS battery of neuropsychological tests, the Hospital Anxiety and Depression Scale (HADS), and the Structured Clinical Interview for the DSM-IV Axis I Disorders (SCID-I). Group-matching and regression analysis were used to control for the effects of age, sex, education, premorbid intelligence, disability, and disease course and duration on cognitive function.<h4>Results</h4>Cannabis users performed significantly more poorly than nonusers on measures of information processing speed, working memory, executive functions, and visuospatial perception. They were also twice as likely as nonusers to be classified as globally cognitively impaired. There were no between-group differences on the HADS measures of depression and anxiety or lifetime SCID-I psychiatric diagnoses.<h4>Conclusion</h4>This cross-sectional study provides empirical evidence that prolonged use of inhaled or ingested street cannabis in patients with MS is associated with poorer performance on cognitive domains commonly affected in this population. Whatever subjective benefits patients may derive from using street cannabis (e.g., pain and spasticity relief) should be weighed against the associated cognitive side effects.