Public narratives of geriatric diseases in the digital space: A topic modelling analysis of YouTube comments

• Analysed 129,613 YouTube comments on dementia, hypertension, and diabetes • Applied topic modelling and sentiment analysis to assess public discourse • Dementia comments showed higher emotional content and misinformation risk • Hypertension and diabetes comments focused on management and treatment • Findings support targeted interventions for neurodegenerative disease awareness In the digital age, social media platforms such as YouTube have become vital sources of health information and public discourse. This study analyses YouTube comments to explore public knowledge, perceptions, and emotional responses to three geriatric diseases dementia, hypertension and diabetes. Comments were collected via YouTube API v3 from the top 100 most-viewed videos for each disease, totalling 129,613 comments. Keywords were selected using Google Trends. After extensive preprocessing, word cloud analysis, sentiment analysis and topic modelling (with parameters optimized through grid search and coherence scores) were performed, identifying five coherent thematic clusters for each disease. Topic modelling identified five key themes per disease: dementia discussions centred on emotions (29%), caregiving (27%), political discourse (17%), fear of cognitive decline (16%), and diet (11%). Hypertension topics focused on treatment searches (28.9%), lifestyle and diet (26.4%), medication and comorbidities (17%), knowledge about blood pressure (16.2%), and work/kidney disease (11.5%). Diabetes conversations emphasized Indian dietary ingredients (37.2%), diet-insulin-blood pressure interactions (20.7%), general diet (16.8%), weight management (13.3%), and emotions/spirituality (12%). Sentiment analysis showed mostly neutral comments across diseases, with 81.4% neutrality in hypertension treatment searches and 89.8% neutrality in diabetes dietary ingredients. Dementia caregiving had the highest negative sentiment (43.5%), while dementia emotions scored 46% positive sentiment. The findings suggest that while hypertension and diabetes prompt neutral, disease management focused discussions, dementia elicits stronger emotional responses and misinformation. This highlights the need for targeted public health interventions and support systems to address the unique challenges of less prevalent neurodegenerative conditions such as dementia.