ArticleNeurology2011
Effects of cannabis on cognitive function in patients with multiple sclerosis.
Article in Neurology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 32 papers, 2 of them syntheses that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
32 citing papers in PubMed, 2 syntheses or guidelines pooled it, 96 citations in OpenAlex.
- Hospital Anxiety and Depression Scale Anxiety subscale (HADS-A) for detecting anxiety disorders in adults.The Cochrane database of systematic reviews · 2025Pooled it
- Pharmacological treatment for memory disorder in multiple sclerosis.The Cochrane database of systematic reviews · 2013Pooled it
- An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain From Spinal Cord Injury and Disease.The journal of pain · 2016Trial
- Trial
- Smoked cannabis for spasticity in multiple sclerosis: a randomized, placebo-controlled trial.CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne · 2012Trial
- Challenges and Innovation for Diagnosing and Treatment of Secondary Progressive Multiple Sclerosis.International journal of molecular sciences · 2026Review
- Temporal Association Between Reported Use of Psychoactive Substances and Cognitive Function in Individuals With Multiple Sclerosis.Archives of physical medicine and rehabilitation · 2026Article
- Cannabis and Cognitive Function in Multiple Sclerosis: Findings From a Large Consecutive Clinical Sample.European journal of neurology · 2025Article
- Phytocanabinoids and synthetic cannabinoids: from recreational consumption to potential therapeutic use - a review.Frontiers in toxicology · 2024Review
- Impact of Low-Dose Dronabinol Therapy on Cognitive Function in Cancer Patients Receiving Palliative Care: A Case-Series Intervention Study.Palliative medicine reports · 2023Article
- Tetrahydrocannabinol and cannabidiol medicines for chronic pain and mental health conditions.Inflammopharmacology · 2022Review
- A bibliometric analysis of the cannabis and cannabinoid research literature.Journal of cannabis research · 2022Article
- Impaired awareness: Why people with multiple sclerosis continue using cannabis despite evidence to the contrary.Brain and behavior · 2021Article
- The why behind the high: determinants of neurocognition during acute cannabis exposure.Nature reviews. Neuroscience · 2021Review
- Cannabinoids in Neurology - Position paper from Scientific Departments from Brazilian Academy of Neurology.Arquivos de neuro-psiquiatria · 2021Article
- A Critical Review of the Role of the Cannabinoid Compounds ΔMolecules (Basel, Switzerland) · 2020Review
- Cognitive impairment in multiple sclerosis: An exploratory analysis of environmental and lifestyle risk factors.PloS one · 2019Article
- Cannabinoids for Treatment of MS Symptoms: State of the Evidence.Current neurology and neuroscience reports · 2018Review
- Attitudes, perceptions, and use of marijuana in youth with multiple sclerosis.Journal of neurology · 2018Article
- Onset Symptoms, Tobacco Smoking, and Progressive-Onset Phenotype Are Associated With a Delayed Onset of Multiple Sclerosis, and Marijuana Use With an Earlier Onset.Frontiers in neurology · 2018Article
Corrections and comments
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Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundWhile 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.
methodsTwo 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.
resultsCannabis 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.
conclusionThis 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.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.