Mapping the Global Research Landscape of co-occurence of Schizophrenia and Substance Use: A Bibliometric Analysis (2000–2023)

Background Schizophrenia and substance use disorders frequently co-occur. Objective This study conducted a bibliometric analysis of the literature on schizophrenia and substance use published between 2000 and 2023 to characterise collaboration patterns, thematic structure, and publication outlets in this field. Methods A Scopus title-field search combining schizophrenia-spectrum terms with a broad set of substance use-related terms (including alcohol, cannabis, nicotine/tobacco, opioids, cocaine, and amphetamines) was restricted to English-language journal articles published between 2000 and 2023. After removing records with missing metadata (n = 7) and duplicates (n = 57), 1,242 documents were retained for analysis. Co-authorship networks (author, organisation, and country level), keyword co-occurrence networks, and journal/source analyses were generated and visualised using standard bibliometric mapping thresholds. Results The author-level co-authorship network comprised 104 authors across 34 clusters; only five organisations, predominantly North American departments of psychiatry, met the minimum productivity threshold, while 42 of 105 countries met the inclusion criterion, forming eight collaboration clusters. Keyword co-occurrence analysis of 144 author keywords (from 1,865 total) yielded 11 thematic clusters spanning neurobiology and psychosis, dual diagnosis and co-morbidity, antipsychotic pharmacotherapy, genetics and risk, nicotine - and cognition, and smoking cessation. Schizophrenia Research, Psychiatry Research, and Psychological Medicine were the most productive journals, with the American Journal of Psychiatry and Archives of General Psychiatry showing the highest citation impact. Conclusions Research on schizophrenia and substance use is thematically diverse but institutionally concentrated within a small number of high-income-country departments, with comparatively weak inter-institutional collaboration. Strengthening cross-national partnerships, particularly with low- and middle-income countries, could broaden the evidence base and applicability of future research.