Association between periodontitis and severity of COVID-19 infection: A case-control study.
Level 4 - case-series / case-control
Case-control study using electronic health records
PubMed 33527378 · doi:10.1111/jcpe.13435
What was done
A case-control study was conducted using national electronic health records from Qatar between February and July 2020. Cases were COVID-19 patients experiencing major complications (death, ICU admission, or assisted ventilation), and controls were COVID-19 patients discharged without major complications. Periodontal conditions were determined from existing dental radiographs. Associations were assessed using logistic regression adjusting for demographic, medical, and behavioral factors.
What was found
In 568 analyzed patients, after multivariable adjustment, periodontitis was associated with higher risks of: - Death: OR = 8.81 (95% CI: 1.00–77.7) - ICU admission: OR = 3.54 (95% CI: 1.39–9.05) - Assisted ventilation: OR = 4.57 (95% CI: 1.19–17.4) Blood levels of white blood cells, D-dimer, and C-reactive protein were significantly higher in COVID-19 patients with periodontitis (specific numeric values not reported in the abstract).
Why it matters
This study provides observational evidence linking pre-existing periodontal disease and systemic inflammation to worsened COVID-19 clinical outcomes.
Limits
The retrospective case-control design cannot establish causality. Confidence intervals, particularly for mortality, are extremely wide, indicating significant imprecision. Periodontitis assessment relied strictly on available dental radiographs rather than full clinical periodontal probings, and residual confounding remains possible.
Cited by
- supports Having gum disease was a risk factor for severe infection or death from COVID-19.