Why and when do patients with pulmonary diseases die?

Introduction and Objective: Department of pulmonary medicine is interested in diagnosis and treatment of diseases like chronic obstructive pulmonary disease (COPD), pneumonia, lung cancer that are significant causes of mortality and morbidity worldwide. In this study, we aimed to investigate mortality rate, death causes and death times in patients who were hospitalized in pulmonary diseases clinic. Methods: File records of patients who died in pulmonary diseases clinic of a university hospital between January 2006 and December 2009 were analysed retrospectively. Results: It was detected that a total of 3553 patients of whom 2258 (64%) were males and 1295 (36%) were females had been hospitalized and of these patients, 243 patients (162 male-67%, 81 female-33%) had died in our clinic. Four-year mortality was estimated as 6.8%. Mean age was found as 68.4 +/- 11.3 years for male patients who died and as 72.5 +/- 12.5 years for female patients. Main causes of death, additional diseases and death times of 202 (83%) patients out of 243 were analysed. According to this, while main causes of death were detected as pneumonia (28.2%), COPD (27.2%), malignities of the lung and pleura (18.1%), pulmonary thromboembolism (6.6%) respectively, causes of death could not be determined in 15 (6.2%). An additional disease was detected in 135 out of 202 (56%) patients. The most common additional diseases were detected as cardiac diseases (25.7%), pulmonary diseases (23.3%), hypertension (20.8%). Respiratory failure (RF) was detected in 99 (49%) of dying patients. Twentyfour hours was divided into four equal periods in order to compare death times of the patients (06:00-12:00 h, 12:00-18:00 h, 18:00-00:00 h, 00:00-06:00 h). According to this, more patients with RF were found to have died during sleeping hours (between 00:00-06:00 h) (p=0.049). In conclusion, pneumonia and COPD are the most common causes of mortality in our clinic. Additionally, the fact that more patients die between 00:00 and 06:00 suggests that staff on duty during these hours should be more carefull. Nevertheless, further miscallenous studies are needed to investigate the causes of death of patients with RF in this time period.