Does smoking status affect cost of hospitalization? Evidence from three main diseases associated with smoking in Iran.

Smoking is recognized as one of the main public health problems worldwide and is accounted for a high financial burden to healthcare systems and the society as a whole. This study was aimed at examining the effect of smoking status on cost of hospitalization among patients with lung cancer (LC), chronic obstructive pulmonary disease (COPD) and ischemic heart diseases (IHD) in Iran in 2014. A total of 1,271 patients (consisting of 415 LC, 427 COPD and 429 IHD patients) were included in the study. Data on age, sex, and insurance status, length of hospital stay and cost of hospitalization were extracted from the medical records of the patients. The smoking status of the patients was obtained through a telephone survey. A generalized linear model (GLM) was used to compare the costs of hospitalization of current, former and never smokers. The analysis was done using Stata v.12. The mean±SD cost of hospitalization per patient was 45.6 ± 41.8 million IR for current smokers, 34.8±23 million IR for former smokers and 27.6±24.6 million IR for never smokers, respectively. The findings indicated that the cost of hospitalization for current and former smokers was 65% and 26% in the unadjusted model and 35% and 24% in the adjusted model higher than for never smokers. The findings revealed that smoking drains a large hospital resource and imposes a high financial burden on the health system and the society. Therefore, efforts should focus on reducing the prevalence of smoking and the negative economic consequences of smoking.