Association Between Periodontal Health Status and COVID-19 Severity: A Cross-Sectional Study

Background and Objectives: The objective of this study was to investigate the relationship between clinical periodontal status and COVID-19 severity, including intensive care unit (ICU) admission and in-hospital mortality, in a cohort of hospitalized patients. Materials and Methods: This single-center, cross-sectional study included 44 patients with polymerase chain reaction-confirmed COVID-19 hospitalized at Buca Seyfi Demirsoy Training and Research Hospital, Izmir, Turkey, between August and December 2021. Of these, 32 (72.7%) were admitted to the ICU and 12 (27.3%) to the inpatient service. All participants underwent a full-mouth clinical periodontal examination to assess probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP), and plaque index (PI). Clinical data, demographics, comorbidities, and validated disease severity scores (GCS, APACHE II and SOFA) were extracted from electronic medical records, and a univariate logistic regression analysis was performed to identify factors associated with in-hospital mortality. Results: Patients admitted to the ICU (n = 32) were significantly older, had a higher prevalence of comorbidities, and showed higher CAL (p = 0.049) and PI (p < 0.001) values than those treated in the inpatient service. Deceased patients (n = 15) had a significantly higher PI than survivors (p = 0.024). In the univariate logistic regression analysis, APACHE II was the only variable significantly associated with in-hospital mortality (OR = 0.867, p = 0.003), however none of the periodontal parameters, including CAL and PI, showed a statistically significant association with mortality. Conclusions: Poorer periodontal findings, particularly higher CAL and PI values, were more frequently observed in patients requiring ICU care. However, periodontal parameters were not significantly associated with in-hospital mortality in univariate analysis. Given the cross-sectional design, small sample size, and lack of multivariable adjustment, these findings should be interpreted as unadjusted associations rather than evidence of an independent or causal relationship.