Pneumonia is a common cause of death in the elderly and may be due to aspiration of oropharyngeal material. Many patients institutionalized in the long-term care setting have poor oral care. Yoneyama and colleagues hypothesized that silent aspiration of oropharyngeal contents may contribute to the development of pneumonia.

Patients in 11 nursing homes in Japan were included in this study if their physical and cognitive impairments had been stable for at least three months before enrollment. The follow-up period was two years. None of the patients had feeding tubes. Pneumonia was diagnosed if the patient had a new radiographically visible infiltrate plus a cough or fever, or subjective shortness of breath. Patients were randomly assigned to the non-oral care protocol (toothbrushing by the patient) or oral care protocol, which included daily toothbrushing by nurses or caregivers without toothpaste. Toothbrushing lasted for approximately five minutes after each meal and included brushing the teeth, the dorsum of the tongue, and the palatal and mandibular mucosa. If the toothbrushing was not “efficient,” povidone iodine was applied to the oropharynx. Dentures were brushed daily, with denture cleanser applied weekly. A dental group provided weekly plaque and calculus control in the oral care group as necessary.

There were 184 patients in the oral care group and 182 in the non-oral care group. In the non-oral care group, 29 percent of the patients had febrile days, compared with 15 percent in the oral care group. Overall, pneumonia developed in 19 percent of those without oral care and in 11 percent of those with oral care. Patients with pneumonia who did not receive oral care were nearly twice as likely to die of this illness than those with pneumonia who received oral care. Rates were similar whether the patients had dentures or not.

The authors conclude that lack of oral care and failure to remove latent oral infections may play a large role in the development of pneumonia in elderly patients in nursing homes. Oral care in the elderly, whether they are edentulous or not, was associated with lower rates of pneumonia and death from pneumonia.