Toothbrushing tied to lower rates of pneumonia among hospitalised patients

05 January 2024

Researchers say toothbrushing is associated with lower rates of hospital-acquired pneumonia, lower rates of ICU mortality, shorter duration of mechanical ventilation, and shorter ICU length of stay.

A new study by investigators from Brigham and Women’s Hospital, a founding member of the Mass General Brigham healthcare system, and Harvard Pilgrim Health Care Institute examined whether daily toothbrushing among hospitalised patients is associated with lower rates of hospital-acquired pneumonia and other outcomes.

The team combined the results of 15 randomised clinical trials that included more than 2,700 patients and found that hospital-acquired pneumonia rates were lower among patients who received daily toothbrushing than those who did not.  The results were especially compelling among patients on mechanical ventilation. Their results are published in JAMA Internal Medicine.

“The signal that we see here towards lower mortality is striking—it suggests that regular toothbrushing in the hospital may save lives,” said Michael Klompas, corresponding author and professor of population medicine at Harvard Pilgrim Health Care Institute. “It’s rare in the world of hospital preventative medicine to find something like this that is both effective and cheap. Instead of a new device or drug, our study indicates that something as simple as brushing teeth can make a big difference.” 

Hospital-acquired pneumonia occurs when bacteria in the mouth enter a patient’s airways and infect their lungs. Patients experiencing frailty or patients with a weakened immune system are particularly susceptible to developing hospital-acquired pneumonia during their hospital stay. However, adopting a daily toothbrushing regimen can decrease the amount of bacteria in the mouth, potentially lowering the risk of hospital-acquired pneumonia from occurring.

The team conducted a systematic review and meta-analysis to determine the association between daily toothbrushing and hospital-acquired pneumonia. Using a variety of databases, the researchers collected and analysed randomised clinical trials from around the world that compared the effect of regular oral care with toothbrushing versus oral care without toothbrushing on the occurrence of hospital-acquired pneumonia and other outcomes.

The team’s analysis found that daily toothbrushing was associated with a significantly lower risk for hospital-acquired pneumonia and ICU mortality.  In addition, the investigators identified that toothbrushing for patients in the ICU was associated with fewer days of mechanical ventilation and a shorter length of stay in the ICU.

Most of the studies in the team's review explored the role of a teeth-cleaning regimen in adults in the ICU. Only two of the 15 studies included in the authors’ analysis evaluated the impact of toothbrushing in non-ventilated patients.  The researchers are hopeful that the protective effect of toothbrushing will extend to non-ICU patients, but additional studies focusing on this population are needed to clarify if, in fact, this is the case. 

Micheal added, “The findings from our study emphasise the importance of implementing an oral health routine that includes toothbrushing for hospitalised patients.  Our hope is that our study will help catalyse policies and programs to ensure that hospitalised patients regularly brush their teeth.  If a patient cannot perform the task themselves, we recommend a member of the patient’s care team assist.”