Online Search Trends and Quality of Web-Based Information on the Relationship Between Periodontal and Cardiovascular Diseases Worldwide

Abstract

Background: Periodontal disease is a highly prevalent chronic inflammatory condition increasingly linked to cardiovascular disease, yet the quality and accessibility of online information regarding this association remain insufficiently characterized. Objectives: To evaluate worldwide online search behavior concerning the relationship between periodontal disease and cardiovascular disease and to assess the quality, transparency, readability, and completeness of web-based information available to lay users. Materials and Methods: This cross-sectional infodemiological and web-content analysis used Google Trends data from January 2010 to December 2025 and assessment of 120 English-language webpages retrieved through Google searches. Google Trends data were downloaded on 15 January 2026, after the complete 2025 monthly dataset was available, and Google webpage searches were performed on 16 January 2026. Search expressions combining periodontal and cardiovascular terms were analyzed as monthly relative search volume values and summarized as annual means, quarterly means, and predefined period blocks. Website quality was evaluated using DISCERN, JAMA benchmark criteria, Health on the Net certification, readability formulas, a seven-domain content-completeness checklist, and an additional source-channel/commercial-orientation check to identify whether eligible non-medical pages were media-, social-media-, influencer-, or commerce-associated. Results: Relative search volume increased over time for combined periodontal-cardiovascular queries, with higher mean values in 2020-2025 than in earlier periods. The overall mean relative search volume increased from 21.4 +/- 5.8 in 2010-2014 to 34.7 +/- 7.6 in 2015-2019 and 52.9 +/- 10.3 in 2020-2025. Patient-centered expressions such as "gum disease heart disease" generated higher relative search volume than technical expressions. The final webpage sample included academic/professional sources (26.7%), hospital/clinic sources (24.2%), commercial sources (20.8%), news/media sources (15.8%), and miscellaneous sources (12.5%). No standalone social-media or influencer-posted page met the eligibility criteria as a patient-facing textual webpage. Mean DISCERN score was 46.8 +/- 12.7. Only 18.3% of webpages fulfilled all four JAMA benchmarks and 14.2% displayed a HONcode seal. Academic/professional sources had higher DISCERN, JAMA, and completeness scores than commercial and news/media websites (p < 0.001). Readability was generally above the recommended patient level. Conclusions: Worldwide online search activity related to the periodontal-cardiovascular relationship increased in relative terms during the study period. However, relative search volume reflects normalized search behavior rather than absolute public interest, disease prevalence, or clinical concern. Online information was heterogeneous in quality, transparency, completeness, and readability. These findings support the need for professionally curated, readable, and evidence-based digital resources that communicate both the importance and the limitations of current knowledge on the periodontal-cardiovascular association.