AbstractBackgroundThe Preventing Dementia Massive Open Online Course (PD‐MOOC) is one of several initiatives aiming to increase dementia risk knowledge and promote risk‐reducing behaviour. These initiatives primarily reach advantaged individuals, increasing health inequities. Previously, thematic analysis of PD‐MOOC participant feedback identified frequent reports of sharing dementia risk information with others. Interpersonal communication often introduces information to people from a broader demographic and may increase the impact of dementia risk education. This study investigated the diffusion of dementia risk reduction knowledge and behaviour beyond PD‐MOOC participants.MethodThe PD‐MOOC attracted over 99,000 enrolments from 2016 to 2019. Responses to surveys completed by participants before (demographics) and after (course feedback) the PD‐MOOC were analysed. Qualitative statements were characterised using key word filtering and subsequent thematic analysis. Chi‐squared tests of homogeneity with Bonferroni adjustments for multiple comparisons were used to determine significant information sharing patterns.ResultOlder people, females, health sector workers and people with a post‐secondary education were over‐represented among PD‐MOOC participants. Participants expressed an eagerness to share the MOOC with others, with 98.8% of respondents agreeing they “would recommend the MOOC to others”. 25% of responding participants discussed sharing PD‐MOOC information in their response to the question “If you have already applied your MOOC learning, please tell us how”. Among those who reported sharing information with specific people, family members were mentioned most frequently, followed by friends and colleagues. Significantly more responses discussed sharing information with males than females (p < 0.001) and with people outside the health sector than within (p < 0.001). Some participants reported sharing information about specific risk domains; physical activity was mentioned most frequently, followed by cognitive stimulation and diet. Additionally, some reported that the person with whom they shared information altered their behaviour; increased physical activity was most commonly reported, followed by a general improved lifestyle and a change in diet.ConclusionInformation sharing transmits dementia risk information to, and promotes behaviour change among, people who are demographically less represented in the PD‐MOOC, extending the reach and impact of this educational intervention. The PD‐MOOC enables dementia risk reduction beyond those educated.