Identifying Stigma Phenotypes in Social Media Narratives of Substance Use: Observational Study.

backgroundIndividuals with substance use problems experience stigma in different contexts. Identifying characteristic situations in which stigma occurs or manifests-stigma phenotypes-can serve as important leverage points for future intervention.

objectiveThis paper aims to (1) identify stigma phenotypes expressed in social media narratives related to substance use stigma and (2) explore the similarities and differences between the stigma phenotypes from a social ecological perspective.

methodsWe collected Reddit posts pertaining to 3 substances-alcohol, cannabis, and opioids. We performed feature engineering using a combination of content analysis, machine learning, and keyword-based methods to predict variables at different levels of the social ecological framework. Leveraging these features, we applied the fuzzy c-means clustering algorithm on the subset of posts containing stigma to extract stigma phenotypes, where a phenotype is defined by four main dimensions: (1) the stigma mechanism present (eg, internalized stigma, anticipated stigma, or enacted stigma), (2) the substance used (eg, alcohol, cannabis, or opioids), (3) the settings involved (eg, work, school, or home), and (4) the actors involved (eg, family, friends, or partners). Finally, we used Kruskal-Wallis and Dunn post hoc tests to examine the differences between stigma phenotypes with respect to specific ecological factors.

resultsWe derived 7 stigma phenotypes from stigma-related posts by 8627 authors. The phenotypes can be categorized into 4 groups: internalized stigma-only, anticipated stigma, enacted stigma-only, and mixed-stigma phenotypes. Narratives on internalized stigma phenotypes focused on the self, with minimal reference to settings and actors. One phenotype focused on anticipated stigma and was characterized by a high proportion of opioid use mentions (707/1217, 58.09% of the authors) and references to the health care setting (647/1217, 53.16% of the authors). Posts associated with the enacted stigma-only phenotypes included substantial representation of settings and actors. Narratives in the mixed-stigma phenotypes often involved more than one stigma mechanism, setting, and actor, with home and family being the most salient factors. The phenotypes differed from one another with respect to social ecological factors, including loneliness and social isolation, use of treatment services, presence of health care providers, community and support groups, society, and legalization.

conclusionsThese findings provide valuable insights that help inform the design and development of interventions targeted at different stigma phenotypic groups from a social ecological perspective.