Risk Factors of Aspiration Pneumonia in Alzheimer’s Disease Patients

Abstract

Background: Pneumonia is the reported cause of death of a high proportion of Alzheimer’s disease (AD) patients. Objectives: This study assessed swallowing function to explore the potential risk factors of aspiration pneumonia in AD patients. Methods: Data were gathered on 121 AD patients (mean age 78.2, SD 7.5, male/female ratio = 48/73) treated in two psychiatric hospitals. Multiple logistic regression analysis was used to estimate odds ratios for the risk of aspiration pneumonia. The following risk factors were considered: age, severity of dementia, silent brain infarction (SBI) in the basel ganglia, use of psychotropic drugs (neuroleptics and benzodiazepines), and gender. The latency time of the swallowing reflex was analyzed (1) among groups based on the severity of dementia; (2) between groups with and without SBI in the basal ganglia; (3) before and after the use of psychotropic drugs in the group without SBI in the basal ganglia, and (4) between males and females. Results: Aspiration pneumonia in ambulatory AD patients was significantly and independently associated with severe dementia, presence of SBI in the basal ganglia, intake of neuroleptics, and the male gender. The mean latency of the swallowing reflex in the severe AD group was significantly longer compared to that in the mild-to-moderate AD group. The mean latency of the swallowing reflex after the intake of neuroleptics was significantly prolonged compared to that obtained before any neuroleptic intake, whereas there was no significant difference in the mean latency of the swallowing reflex before and after benzodiazepine intake. Conclusion: We recommend the use of the smallest efficacious dosage of neuroleptics especially in treating severely demented AD patients with basal-ganglia infarction. As soon as the behavioral and psychiatric problems are resolved, drug tapering or discontinuation should be considered in order to prevent life-threatening aspiration pneumonia.