Aspiration pneumonia develops after the aspiration of colonized oropharyngeal contents.1 The elderly or patients with cerebrovascular disease (CVD) are often subjected to aspiration pneumonia because bacteria colonized in the oral cavity and oropharynx easily enter the lung during sleep and usually undergo repeated silent aspiration.2 Aspiration pneumonia is increasing in patients with dysphagia, and aspiration pneumonia-associated mortality is a most serious problem in elderly patients. Interestingly, it has been reported that oral health care for elderly patients in nursing homes reduces bacterial pneumonia.3,4 Therefore, it is very important to determine the characteristics of oropharyngeal microflora in patients with CVD to plan the optimum oral care to prevent aspiration pneumonia. From this standpoint, we investigated initial pharyngeal microflora in patients with CVD and dysphagia requiring daily nursing (Table 1). This study protocol was approved by the Ethics Committee of Chikamori Rehabilitation Hospital. We collected swab samples from the oropharynx of 55 patients with CVD (26 with dysphagia and 29 without dysphagia). To count the colony-forming units, the swabs, which were diffused into sterile medium, were inoculated onto agar plate using the spiral system as described previously.5 In addition to bacterial culture, polymerase chain reaction with bacterial-specific primers was used for bacterial identification. A higher prevalence (38.5%; 10/26) of Pseudomonas aeruginosa was observed in patients with CVD and dysphagia than in patients with CVD and without dysphagia (3.4%; 1/29; P < .01). The prevalence of Staphylococcus spp (30.7% and 24.1%, respectively) and Candida spp (46.2% and 31.0%, respectively) in both groups was similar. Moreover, the bacterial number of P aeruginosa in patients with CVD and dysphagia was significantly higher than in the group without dysphagia. Ten (47.6%) of 21 patients with CVD and dysphagia who needed complete or some assistance in daily living had P aeruginosa in their oropharyngeal microflora. Regarding the mode of nutritional intake, seven (63.6%) of 11 patients with CVD and dysphagia who were administered nutrition through a catheter had P aeruginosa in their oropharyngeal microflora. Interestingly, four (25%) of 16 patients with CVD and dysphagia whose test results were negative for P aeruginosa in oropharyngeal microflora were also administered nutrition through a catheter, and only one (3.4%) of 29 patients with CVD and without dysphagia had positive test results for P aeruginosa in oropharyngeal microflora. More importantly, these observations suggest that the high detection rate of P aeruginosa from oropharyngeal microflora in patients with CVD is increased by the status of dysphagia, not catheter use. Our data highlight that the care of oropharyngeal microflora, especially P aeruginosa, may be important to prevent aspiration pneumonia in patients with CVD and dysphagia.