Effect of dental prophylaxis on long-term systemic risks in therapy-induced oral mucositis: A real-world cohort analysis.

e24195 Background: Oral ulcerating mucositis (OUM) is a common complication of radiation and antineoplastic therapy, often leading to pain, infection risk, and long-term systemic effects. Dental prophylaxis (DP) may mitigate these risks by improving oral hygiene, but its long-term impact remains understudied. The objective of this study is to evaluate the association between DP and long-term outcomes, including pain, sepsis, malaise, fever, lymphadenopathy, vascular diseases, respiratory complications, pleural diseases, and ischemic heart disease (IHD), in adults with therapy-induced OUM. Methods: Retrospective cohort study using the TriNetX federated health research network (deprecated COVID-19 Research Network, 89 healthcare organizations). Cohort 1 included 41,958 patients aged ≥18 years with OUM due to radiation or antineoplastic therapy without DP. Cohort 2 included 387 similar patients with DP. Index event was the first OUM diagnosis; outcomes were assessed starting 1-day post-index with no end date (up to 20 years). Propensity score matching was not applied. Measures of association (risk difference, ratio, odds ratio), Kaplan-Meier survival, and number of instances for each outcome, excluding patients with prior outcomes where specified. Results: Patients without DP showed higher risks for several outcomes. For lymphadenopathy (including prior occurrences), risk was 0.213 vs 0.158 (risk difference 0.055 [95% CI, 0.018-0.091]; P = 0.008), with reduced survival probability (48.89% vs 69.45%; log-rank P < 0.001; hazard ratio [HR] 1.560 [95% CI, 1.213-2.007]). Respiratory diseases had higher risk (0.296 vs 0.241; P = 0.077) and worse survival (44.85% vs 48.93%; log-rank P = 0.006; HR 1.461 [95% CI, 1.113-1.919]). IHD risk was elevated (0.122 vs 0.087; P = 0.054), with poorer survival (67.89% vs 69.03%; log-rank P = 0.008; HR 1.644 [95% CI, 1.133-2.384]). No significant differences were observed for pain, sepsis, malaise, fever, arterial diseases, or pleural diseases. Conclusions: DP was associated with reduced long-term risks of lymphadenopathy, respiratory complications, and IHD in patients with therapy-induced OUM. These findings suggest potential benefits of routine dental interventions in oncology care, warranting prospective studies.