Factors Associated with Pneumonia-caused Death in Older Adults with Autopsy-confirmed Dementia

OBJECTIVE: A better understanding of risk factors for pneumonia-caused death may help to improve the clinical management of dementia. METHODS: A retrospective observational study was conducted by reviewing the medical charts and autopsy reports of 204 patients who were admitted to hospital, underwent a post-mortem examination, and who were neuropathologically diagnosed with dementia. The risk factors for pneumonia-caused death were examined both as underlying and immediate causes of death using logistic regression models. RESULTS: A high frequency of pneumonia-caused death was observed both in underlying- (37.3%) and immediate- (44.1%) cause of death, but varied according to the subtypes of dementia. The factors related to pneumonia-caused death (underlying) were subtypes of dementia; Alzheimer's disease (odds ratio [OR], 2.891; 95% confidence interval [CI], 1.459-5.730); argyrophilic grain disease (OR, 3.148; 95% CI, 0.937-10.577); and progressive supranuclear palsy (OR, 34.921; 95% CI, 3.826-318.775), dysphagia (OR, 2.045; 95% CI, 1.047-3.994), diabetes mellitus (OR, 3.084; 95% CI, 1.180-8.061) and conversely related with heart failure (OR, 0.149; 95% CI, 0.026-0.861). Factors relating to pneumonia-caused death (immediate) were incidence of pneumonia during hospitalizations (OR, 32.579; 95%CI, 4.308-246.370), gender-male (OR, 2.060; 95% CI, 1.098-3.864), and conversely related with malignant neoplasm (OR, 0.220; 95% CI, 0.058-0.840). CONCLUSION: The different factors relating to the pneumonia-caused death were evaluated depending on whether pneumonia was the underlying- or immediate-cause of death. Strengthening clinical management on dysphagia and diabetes mellitus, and preventing incidence of pneumonia during hospitalization appear to be the important for the terminal stage of hospitalized patients with dementia.