ACE and susceptibility to pneumonia measurement: Previous studies showed that ACE inhibitors can prevent aspiration pneumonia among elderly stroke patients.6–11 One international clinical trial of ACE inhibitor use among stroke patients showed that ACE inhibitor use had a preventive effect on pneumonia only in Asian populations.12 Because stroke patients may have impaired cough reflex and are more likely to be hospitalized for aspiration pneumonia, we examined the effects of ACE inhibitors on pneumonia risk among patients with a history of stroke.