Risk of Stroke-Associated Pneumonia and Oral Hygiene

Abstract

Background: Pneumonia is a major complication of stroke, but effective prevention strategies are lacking. Since aspiration of oropharyngeal secretions is the primary mechanism for development of stroke-associated pneumonia, strategies that decrease oral colonization with pathogenic bacteria may help curtail pneumonia risk. We therefore hypothesized that systematic oral care protocols can help decrease pneumonia risk in hospitalized stroke patients. In this study, we investigated the impact of a systematic oral hygiene care (OHC) program in reducing hospital-acquired pneumonia in patients with acute-subacute stroke.

Methods: This study compared the proportion of pneumonia cases in hospitalized stroke patients before and after implementation of a systematic OHC intervention. All patients hospitalized with acute ischemic stroke or intracerebral hemorrhage admitted to a large, urban academic medical center in Boston, Mass., USA from May 31, 2008, to June 1, 2010 (epoch prior to implementation of OHC), and from January 1, 2012, to December 31, 2013 (epoch after full implementation of OHC), who were 18 years of age and hospitalized for ≥ 2 days were eligible for inclusion. The cohort in the first epoch constituted the control group whereas the cohort in the second epoch formed the intervention group. Multivariate logistic regression was used to control for confounders. The main outcome measure was hospital-acquired pneumonia, defined via International Classification of Diseases, Ninth Revision, Clinical Modification codes.

Results: The cohort comprised 1,656 admissions (707 formed historical controls; 949 were in the intervention group). The unadjusted incidence of hospital-acquired pneumonia was lower in the group assigned to OHC compared to controls (14 vs. 10.33%; p = 0.022) with an unadjusted OR of 0.68 (95% CI 0.48-0.95; p = 0.022). After adjustment for influential confounders, the OR of hospital-acquired pneumonia in the intervention group remained significantly lower at 0.71 (95% CI 0.51-0.98; p = 0.041).

Conclusion: In this large hospital-based cohort of patients admitted with acute stroke, systematic OHC use was associated with decreased odds of hospital-acquired pneumonia.