Background: It remains unclear how swallowing assessment can help clinicians to predict the risk for pneumonia in elderly persons after ischemic stroke. A prospective case-control study was conducted to evaluate the prognostic utility of swallowing ability assessments.
Methods: Participants were 136 elderly persons who had an acute ischemic stroke 3-12 months previously. They were separated into four groups based on their history of repeated episodes of pneumonia in combination with swallowing ability: Group 1 had neither repeated pneumonia nor swallowing abnormality (n = 69); group 2 had repeated pneumonia but no swallowing abnormality (n = 0); group 3 had swallowing abnormality but no repeated pneumonia (n = 54); and group 4 had both swallowing abnormality and repeated pneumonia (n = 13). The follow-up period was as long as 2.2 years. Outcomes and causes of death were compared among the groups.
Results: During the study, the overall mortality rate was higher in group 3 (24 deaths, 44.4%) and group 4 (9 deaths, 69.2%) than in group 1 (3 deaths, 4.3%, both p <.05). The annual mortality rate from pneumonia was also significantly higher in group 3 (21.2%) and group 4 (38.2%) than in group 1 (0.8%, p <.0001). The odds ratio for patients who subsequently died of pneumonia was 46.8 between groups 1 and 3.
Conclusions: The high sensitivity (.96) and specificity (.68) of swallowing ability indicate that the method is useful for identifying those persons at greatest risk for pneumonia and death after ischemic stroke.