{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T18:31:01Z","timestamp":1764959461891,"version":"3.46.0"},"reference-count":52,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T00:00:00Z","timestamp":1764892800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"funder":[{"name":"the Stanley Center for Psychiatric Research"},{"name":"United States' National Institute of Mental Health","award":["R01MH120642"],"award-info":[{"award-number":["R01MH120642"]}]},{"name":"United States' National Institute of Mental Health","award":["R01MH120642"],"award-info":[{"award-number":["R01MH120642"]}]},{"name":"United States' National Institute of Mental Health","award":["R01MH120642"],"award-info":[{"award-number":["R01MH120642"]}]},{"name":"United States' National Institute of Mental Health","award":["U01MH125047"],"award-info":[{"award-number":["U01MH125047"]}]},{"name":"the Intramural Research Program of the National Institutes of Health","award":["Z99 HD999999"],"award-info":[{"award-number":["Z99 HD999999"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Substance use disorders are increasingly prevalent in sub-Saharan African countries, with evident bidirectional risk for people with severe mental illness (SMI) resulting in more severe and chronic courses. This study examines the association between common substance use, including khat and alcohol, and SMI, comparing affected individuals to age and sex-matched controls in Ethiopia.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Method<\/jats:title>\n                    <jats:p>This study uses data collected as part of the NeuroGAP-Psychosis project, a large multi-country case-control genetics study. This case-control study consisted of 6,500 people with severe mental illness and age and sex-matched 6,500 controls in Ethiopia. Current substance use was defined as any use within the last three months, while current regular use was defined as at least weekly use within the previous three months. Descriptive statistics were used to determine the demographic distribution of participants, and logistic regression was used to estimate the association between substance use and severe mental illness.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Most cases were men (65.8%; n\u2009=\u20094,276) with a mean age of 36.9 (SD\u2009=\u200910.3) years, while the controls were 64.7% (n\u2009=\u20094,204) men with a mean age of 36.2 (SD\u2009=\u200910.9) years. Current use of tobacco, alcohol, khat, and cannabis was 15.1%, 17.2%, 20.4% and 1.0% among cases and 6.0%, 41.5%, 12.5%, and 0.8% among controls, respectively. The adjusted odds of regular tobacco and khat use were 4.8 (95% CI: 4.0, 5.9) and 1.6 (95% CI: 1.4, 1.8) times higher in cases than in controls, respectively. However, regular use of alcohol was 0.1 (95% CI: 0.1, 0.2) times lower among cases than among controls.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Tobacco and khat use were higher among cases than controls, while alcohol and cannabis use were more prevalent in controls. The high prevalence of khat use is particularly problematic in people with SMI as it adversely affects the course and outcome of mental illness. Tobacco smoking also contributes to physical health morbidity and associated premature mortality. Therefore, evidence-based screening and treatment services are warranted to mitigate the harmful health outcomes of khat use and tobacco consumption among individuals with SMI.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0332107","type":"journal-article","created":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T18:25:51Z","timestamp":1764959151000},"page":"e0332107","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Patterns of substance use in people with severe mental illness: A case-control study in Ethiopia"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0710-3435","authenticated-orcid":true,"given":"Melkam","family":"Alemayehu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Awoke","family":"Mihretu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruth","family":"Tsigebrhan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Manasi","family":"Sharma","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7934-548X","authenticated-orcid":true,"given":"Bizu","family":"Gelaye","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Solomon","family":"Teferra","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,12,5]]},"reference":[{"issue":"2","key":"pone.0332107.ref001","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/S2215-0366(22)00002-5","article-title":"The true global disease burden of mental illness: still elusive","volume":"9","author":"D Vigo","year":"2022","journal-title":"Lancet Psychiatry"},{"issue":"9904","key":"pone.0332107.ref002","doi-asserted-by":"crossref","first-page":"1575","DOI":"10.1016\/S0140-6736(13)61611-6","article-title":"Global burden of disease attributable to mental and substance use disorders: findings from the Global Burden of Disease Study 2010","volume":"382","author":"HA Whiteford","year":"2013","journal-title":"Lancet"},{"issue":"2","key":"pone.0332107.ref003","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1177\/0020764012471918","article-title":"The impact of psychosis on social inclusion and associated factors","volume":"60","author":"H Killaspy","year":"2014","journal-title":"Int J Soc Psychiatry"},{"volume-title":"GBD Compare: Ethiopia","year":"2019","author":"IHME","key":"pone.0332107.ref004"},{"key":"pone.0332107.ref005","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1016\/bs.adgen.2016.08.001","article-title":"Genetics of schizophrenia: historical insights and prevailing evidence","volume":"96","author":"J van de Leemput","year":"2016","journal-title":"Adv Genet"},{"issue":"10","key":"pone.0332107.ref006","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1007\/s11920-019-1091-3","article-title":"Non-genetic factors in schizophrenia","volume":"21","author":"SA Stilo","year":"2019","journal-title":"Curr Psychiatry Rep"},{"issue":"19","key":"pone.0332107.ref007","doi-asserted-by":"crossref","first-page":"2511","DOI":"10.1001\/jama.1990.03450190043026","article-title":"Comorbidity of mental disorders with alcohol and other drug abuse. 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