Impact of pneumonia on hyperactive delirium in end-stage lung cancer patients

Purpose Patients with incurable lung cancer often receive palliative care. Hyperactive delirium is a burden not only for the patient’s family but also for caregivers. There are no reports describing the risk factors for delirium among lung cancer patients. The present study investigated the frequency of incidence and risk factors for hyperactive delirium among end-stage lung cancer patients. Methods Patients who died of lung cancer in our institute from January 2010 to December 2010 were retrospectively investigated. Information was obtained from medical records, and patients who developed hyperactive delirium (delirium group, group D) were compared with patients who did not (control group, group C) based on clinical and laboratory data. Results A total of 146 patients (median age, 70 years; 80 % male) died of lung cancer. Thirty-one (21.2 %) patients developed hyperactive delirium. Sex ( P = 0.0093) and pneumonia ( P = 0.023) were statistically significant variables in univariate analysis. Pneumonia occurred in 27.4 % of all patients. The incidence of pneumonia was 45.2 % in group D and 22 % in group C. Only pneumonia (odds ratio, 2.89; 95 % confidence interval, 1.22–6.85; P = 0.016) was identified as a significant factor for predicting hyperactive delirium in multivariate analysis. Conclusions Pneumonia was identified as a significant risk factor for the development of hyperactive delirium among end-stage lung cancer patients.