Relationship between oral health and prognosis in patients with empyema: Single center retrospective study with propensity score matching analysis

BACKGROUND: Empyema is a life-threatening infection often caused by oral microbiota. To the best of our knowledge, no reports have investigated the association between the objective assessment of oral health and prognosis in patients with empyema. MATERIALS AND METHODS: A total of 63 patients with empyema who required hospitalization at a single institution were included in this retrospective study. We compared non-survivors and survivors to assess risk factors for death at three months, including the Renal, age, pus, infection, diet (RAPID) score, and Oral Health Assessment Tool (OHAT) score. Furthermore, to minimize the background bias of the OHAT high-score and low-score groups determined based on the cut-off value, we also analyzed the association between the OHAT score and death at 3 months using the propensity score matching method. RESULTS: The 3-month mortality rate was 20.6% (13 patients). Multivariate analysis showed that a RAPID score ≥5 points (odds ratio (OR) 8.74) and an OHAT score ≥7 points (OR 13.91) were significantly associated with death at 3 months. In the propensity score analysis, a significant association was found between a high OHAT score (≥7 points) and death at 3 months (P = 0.019). CONCLUSION: Our results indicated that oral health assessed using the OHAT score may be a potential independent prognostic factor in patients with empyema. Similar to the RAPID score, the OHAT score may become an important indicator for the treatment of empyema.