Risk factors of aspiration pneumonia in patients with severe benzodiazepine, zopiclone, or zolpidem overdose

Abstract Background Benzodiazepines, zopiclone, and zolpidem account for the most common hypnotics overdose in Hong Kong. Patients with severe benzodiazepines, zopiclone, or zolpidem overdose presenting in a comatose state are at risk of development of aspiration pneumonia. The objective of this study was to investigate the risk factors of aspiration pneumonia in this group of patients. Methods This was a retrospective cohort study. The study data were retrieved from the Hong Kong Poison Information Centre database. Patients who had been poisoned with benzodiazepines, zopiclone, and zolpidem presenting to Accident and Emergency Departments in Hong Kong with coma over the period of 1 January 2008 to 31 December 2023 were recruited. The outcome of analysis was the development of aspiration pneumonia in the same hospital admission. Results A total of 177 patients were included in the final analysis. The mean age was 56.7 years. The rate of developing aspiration pneumonia was 25%. Univariate analysis at p ‐value < 0.05 showed that (1) older age, (2) hypertension, (3) respiratory rate, (4) white blood cell count, (5) serum sodium, (6) serum creatinine, (7) use of antidote, (8) intubation in the Accident and Emergency Department (AED), and (9) admitted to intensive care unit were associated with aspiration pneumonia. The multivariate logistic regression model showed that older age and higher initial white blood cell count were risk factors for aspiration pneumonia. Conclusion Among patients with severe benzodiazepine, zopiclone, or zolpidem overdose, older age and higher white blood cell count were risk factors that strongly associated with the development of aspiration pneumonia.