Objectives: Respiratory infection is a major cause of death in the elderly. We have evaluated the role of professional oral health care (POHC) by dental hygienists in reducing respiratory infections in elderly persons requiring nursing care.
Methods: Two populations of elderly persons, one receiving POHC and one not, were examined to determine numbers of microorganisms, potent pathogens of respiratory infection, enzymatic activity in saliva, fevers, prevalence of fatal aspiration pneumonia and prevalence of influenza.
Results: In the first population, we found a high prevalence of potent respiratory pathogens such as Staphylococcus species, Pseudomonas aeruginosa and Candida albicans. Patients who received POHC showed a lower prevalence for these pathogens than those who did not. The ratio of fatal aspiration pneumonia in POHC patients was significantly lower than that in patients without POHC (non-POHC) over a 24-month period (P < 0.05). The prevalence of a fever of 37.8 degrees C or more in POHC patients was significantly lower than that in the non-POHC group (P < 0.05). In the second study population, we investigated the effects of POHC on infection with influenza over a 6-month period. In the POHC group, neuraminidase and trypsin-like protease activities decreased, and one of 98 patients was diagnosed with influenza; whereas, in the non-POHC group, nine of 92 patients were diagnosed with influenza. The relative risk of developing influenza while under POHC was 0.1 (95% CI 0.01-0.81, P = 0.008).
Conclusion: These results suggest that POHC by dental hygienists is effective in preventing respiratory infections in elderly persons requiring nursing care.