Background: Over the past decade, social media data have gained special interest across various sectors, specially in medicine where these data are being utilized for a variety of purposes, including surveillance, pharmacovigilance, or patient recruitment. Among the social platforms, Reddit is one of the most widely used worldwide. The way in which this social network organises information, in specific subreddits, makes it possible to estimate the popularity and relevance of topics, including medical ones. Although there have been multiple studies in rheumatology using these social media, none have detailed the different rheumatology-specific communities that exist within Reddit.

Objectives: To identify rheumatology-related subreddits; to describe their characteristics and to conduct sentiment analyses to better understand users’ interactions.

Methods: The Reddit search engine, along with a list of 21 commonly used rheumatology terms, was used to identify the candidate subreddits. The subreddit’s name, creation date, number of subscribers, public status, size, and activity since May 2023 to May 2024 information was collected. Exclusion criteria were applied to narrow down the results. Only subreddits with over 1000 subscribers, active, with strong affinity and recoverable through Pushshift.io were extracted. Different metrics and statistics were computed to characterise the subreddits identified in the previous step (e.g., number of users who participate in each subreddit, number of messages, thread length, word count per submissions, subreddits activities, most commented threads per subreddit and so on). Continuous variables were summarised using the median and the first and third quartiles (Q1–Q3). Moreover, a pre-trained model fine-tuned for sentiment analysis was used to classify posts as negative, neutral, or positive.

Results: Of 83 potential subreddits, 20 met the inclusion criteria. The oldest subreddit was r/Fibromyalgia. The number of subscribers ranged from 2k (r/Behcets) to 70k (r/Fibromyalgia) and the ratio comments/submissions was higher in r/ankylosingspondylitis (12.36), Table 1. Almost exponential growth is seen for all communities since 2016-2017. r/Fibromyalgia has the highest number of messages per day.Peak activity occurs between 16:00 and 23:00 and the majority of activity is concentrated in the second half of the year. The patient’s age is a common concern across subreddits. Another majornconcern is the COVID vaccine and its potential impact on patients with RMDs (i.e., r/mctd,r/costochondritis, r/Sjogrens, r/Uveitis). Some of the most commented posts on r/gout are AskMe Anything sessions, where professionals respond to patient’s questions. This highlights patient’s interest in exchanging information with healthcare professionals via social media. The highest percentage of negative comments pertains to mechanical conditions such as costochondritis or back pain, as well as to fibromyalgia, Figure 1.

Conclusion: Reddit provides a valuable platform for studying patient concerns, needs, and perceptions about their RMDs as evidenced by the number of subscribers, the diversity of communities, and the extent of their activity and size. This research contributes to understand how rheumatic and musculoskeletal communities utilize Reddit to discuss health-related topics, potentially informing better patient support and engagement strategies in digital spaces.

REFERENCES: NIL.

Figure 1.

Sentiment in RMDs Reddit communities sorted by negative percentage

Acknowledgements: NIL.

Disclosure of Interests: None declared.

© The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Neither EULAR nor the publisher make any representation as to the accuracy of the content. The authors are solely responsible for the content in their abstract including accuracy of the facts, statements, results, conclusion, citing resources etc.