{
  "abstract": "Background Reasons for first using cannabis (RFUC) may influence later use patterns and mental health outcomes. However, limited research has explored self-medication versus social RFUCs in depth, and their associations with cannabis use patterns and psychopathology in the general population.Objectives We examined RFUCs and their associations with (1) reasons for continuing cannabis use, (2) weekly THC (delta-9-tetrahydrocannabinol) unit consumption and (3) symptoms of paranoia, anxiety and depressive symptoms.Methods We analysed data from the Cannabis&Me (CAMe) population survey (March 2022–July 2024), including 2573 (75.9%) current and 816 (24.1%) past cannabis users aged 18 years or older.Findings Participants reported a mean weekly consumption of 206 THC units (SD=268). Initiating cannabis use for anxiety (β=36.22, p=3.3e−03), depression (β=40.37, p=1.74e−03) or because ‘family members were using it’ (β=87.43, p=1.22e−09) was associated with higher weekly THC units. RFUC to relieve physical discomfort (β=8.89, p=4.12e−07), pain (β=7.24, p=5.56e−06), anxiety (β=9.67, p=1.63e−16), depression (β=9.12, p=1.21e−13) and minor psychotic symptoms (β=16.46, p=1.2e−04) were linked to higher paranoia scores. Similar associations were observed for anxiety and depression. Conversely, starting for fun (β=−3.71, p=3.49e−05) or curiosity (β=−2.61, p=5e−03) was associated with lower paranoia and anxiety. RFUC for ‘boredom’ was linked to increased depression (β=1.09, p=3.8e−03).Conclusions Initiating cannabis use for self-medication is associated with higher average THC consumption, and increased anxiety, depression and paranoia.Clinical implications Asking individuals why they first used cannabis may serve as a cost-effective screening tool to identify those who could benefit from monitoring, support, or referral to intervention services.",
  "authors": [
    {
      "affiliations": [
        "Psychosis Studies, King’s College London, London, UK",
        "South London and Maudsley NHS Foundation Trust, London, UK"
      ],
      "name": "Edoardo Spinazzola"
    },
    {
      "affiliations": [
        "Psychosis Studies, King’s College London Institute of Psychiatry, Psychology and Neuroscience, London, UK"
      ],
      "name": "Hannah Degen"
    },
    {
      "affiliations": [
        "Social, Genetic, and Developmental Psychiatry Centre, King’s College London Institute of Psychiatry Psychology and Neuroscience, London, UK"
      ],
      "name": "Isabelle Austin-Zimmerman"
    },
    {
      "affiliations": [
        "Social, Genetic, and Developmental Psychiatry Centre, King’s College London Institute of Psychiatry Psychology and Neuroscience, London, UK"
      ],
      "name": "Giulia Trotta"
    },
    {
      "affiliations": [
        "South London and Maudsley NHS Foundation Trust, London, UK",
        "King’s College London Department of Addictions, London, UK"
      ],
      "name": "Edward Chesney"
    },
    {
      "affiliations": [
        "Social, Genetic, and Developmental Psychiatry Centre, King’s College London Institute of Psychiatry Psychology and Neuroscience, London, UK"
      ],
      "name": "Zhikun Li"
    },
    {
      "affiliations": [
        "Psychosis Studies, King’s College London Institute of Psychiatry, Psychology and Neuroscience, London, UK",
        "South London and Maudsley Mental Health NHS Trust, London, UK"
      ],
      "name": "Luis Alameda"
    },
    {
      "affiliations": [
        "Psychosis Studies, King’s College London Institute of Psychiatry, Psychology and Neuroscience, London, UK",
        "Department of Psychiatry, The University of Hong Kong Li Ka Shing Faculty of Medicine, Hong Kong, Hong Kong"
      ],
      "name": "Bok Man Leung"
    },
    {
      "affiliations": [
        "Psychosis Studies, King’s College London Institute of Psychiatry, Psychology and Neuroscience, London, UK"
      ],
      "name": "Yifei Lang"
    },
    {
      "affiliations": [
        "University of Porto Institute of Biomedical Sciences Abel Salazar, Porto, Portugal"
      ],
      "name": "Andrea Quattrone"
    },
    {
      "affiliations": [
        "South London and Maudsley NHS Foundation Trust, London, UK",
        "Social, Genetic, and Developmental Psychiatry Centre, King’s College London Institute of Psychiatry Psychology and Neuroscience, London, UK"
      ],
      "name": "Diego Quattrone"
    },
    {
      "affiliations": [
        "King’s College London Department of Forensic and Analytical Science, London, UK"
      ],
      "name": "Erika Castrignanò"
    },
    {
      "affiliations": [
        "King’s College London Department of Forensic and Analytical Science, London, UK"
      ],
      "name": "Kim Wolff"
    },
    {
      "affiliations": [
        "Psychosis Studies, King’s College London Institute of Psychiatry, Psychology and Neuroscience, London, UK"
      ],
      "name": "Robin Murray"
    },
    {
      "affiliations": [
        "Psychology, University of Bath, Bath, UK"
      ],
      "name": "Tom P Freeman"
    },
    {
      "affiliations": [
        "Social, Genetic, and Developmental Psychiatry Centre, King’s College London Institute of Psychiatry Psychology and Neuroscience, London, UK"
      ],
      "name": "Marta Di Forti"
    }
  ],
  "title": "Are reasons for first using cannabis associated with subsequent cannabis consumption (standard THC units) and psychopathology?",
  "uid": "76045487-a8a9-5605-8366-2de9e085164f"
}