Oral hygiene in elderly people in hospitals and nursing homes

Searches were made using Medline, the Cochrane Library, the National Health Service Economic Evaluation database and, by hand, of relevant articles' reference lists.

The search was limited to studies conducted in humans only. The predetermined inclusion criteria were: clinical studies and randomised controlled trials (RCT) that linked oral hygiene with healthcare-associated pneumonia or respiratory tract infection in elderly people. Publications in Dutch, English, German and any of the Nordic languages (Danish, Finnish, Icelandic, Norwegian, Swedish) were included. Articles about authority opinions and reports of expert committees were excluded, as were studies on subjects who required mechanical ventilation or tube feeding.

Data extraction from RCT was focused on the outcomes. Assessments were made of the quality and validity of the studies, using statistical methods to test these. To ensure the consistency of the assessments throughout the study, two authors (EN, PS) performed the data extraction independently, and any disagreements were resolved in consensus meetings. Pooling data from individual studies (meta-analysis) was not deemed appropriate because of heterogeneous study designs, quality of reporting methodological aspects and trial conduct. To provide an overview of additional clinical studies in this research area, the non-RCT studies that were identified were scrutinised for the authors' main conclusion(s).

Fifteen publications, of which five were RCT, fulfilled the inclusion criteria and were considered throughout all the assessments. All of the RCT revealed positive preventive effects of oral care on pneumonia or respiratory tract infection in nursing home residents, with numbers needed to treat ranging from 8.6-15.3.

Available results from RCT provide evidence that mechanical oral hygiene decreases mortality risk from pneumonia and seems to have a clinically relevant preventive effect on nonfatal pneumonia in independent elderly individuals. The data show that providing mechanical oral hygiene may prevent approximately 1 in 10 cases of death from pneumonia in dependent elderly people and indicate a largely similar effect for prevention of pneumonia.