Understanding who uses R eddit: Profiling individuals with a self-reported bipolar disorder diagnosis (2021)

Abstract: Recently, research on mental health conditions using public online data, including Reddit, has surged in NLP and health research but has not reported user characteristics, which are important to judge generalisability of findings. This paper shows how existing NLP methods can yield information on clinical, demographic, and identity characteristics of almost 20K Reddit users who self-report a bipolar disorder diagnosis. This population consists of slightly more feminine- than masculine-gendered mainly young or middle-aged US-based adults who often report additional mental health diagnoses, which is compared with general Reddit statistics and epidemiological studies. Additionally, this paper carefully evaluates all methods and discusses ethical issues.

## introduction and related work people who experience extreme mood states that interfere with their functioning, meet the criteria for bipolar disorder (bd) according to the diagnostic manuals diagnostic and statistical manual of mental disorders (dsm) @xcite and international classification of diseases (icd) @xcite . dsm and icd operationalise extreme mood states in terms of major depressive episodes, 'almost daily depressed mood or diminished interest in activities with additional symptoms for at least 14 days' @xcite and (hypo-)manic episodes, 'a distinct period of abnormally and persistently elevated, expansive, or irritable mood and abnormally and persistently increased goal-directed activity or energy' that lasts at least seven (four) days @xcite . dsm and icd distinguish several bd subtypes based on the lifetime frequency and intensity of (hypo-)manic and depressed episodes. the only requirement for a diagnosis of bipolar i disorder (bd-i) is at least one lifetime manic episode, whereas bipolar ii disorder (bd-ii) requires at least one hypomanic and one major depressive episode @xcite . cyclothymic disorder applies to numerous periods of hypomanic and depressive symptoms during at least two years that do not meet criteria for hypomanic or major depressive episodes @xcite . bipolar mood episodes are often recurring @xcite , so many individuals living with bd require life-long treatment @xcite and have a heightened suicide risk @xcite . however, characteristics and outcomes of people meeting bd criteria are diverse, with some living well, (e.g., @xcite and even functioning on a high level @xcite . ## ethical considerations at least four main ethical considerations arise for the work presented here: concerns around (1) consent and (2) anonymity of reddit users, around the (3) selection, category labels, and assignment of user characteristics (mh diagnoses, age, country, gender), and (4) potentially harmful uses of the presented dataset and methods. the lancaster university faculty of health and medicine research ethics committee reviewed and approved this study in may 2019 (reference number fhmrec18066). ## results and discussion the self-reported bd diagnosis matching method identified 19,685 reddit users who together had 21,407,595 public reddit posts between march 2006 and march 2019. compared to 9k unique user accounts who posted in the four largest bd-related subreddits in may 2020, this likely only constitutes a small fraction of reddit users with a bd diagnosis that could be reliably automatically identified (see following subsection). ## conclusion this paper set out to automatically profile reddit users under consideration of ethical aspects. a combination of pattern-based and previously published nlp methods served to estimate clinical, demographic, and identity characteristics of nearly 20k reddit users with a self-reported bd diagnosis. half of the reddit users disclosed mh diagnoses besides bd and 80% were located in the us. from the users for which age or gender could be estimated, 80% were between 18-49 years old and 52% performed or identified with feminine gender. these findings indicate about which populations bd-focused research on reddit may generalise. additionally, this work may serve as a model for how to provide more information on other specific reddit populations as requested by recent transparency and accountability movements in nlp. mark zimmerman and theresa a. morgan. 2013. problematic boundaries in the diagnosis of bipolar disorder: the interface with borderline personality disorder. current psychiatry reports, 15(422).