Lung cancer in relation to smoking including relighting cigarette butts: Kathmandu Valley Nepal “an unmatched case control study”

Abstract

Background: Lung cancer is one of the most common cancers in Nepal causing 14.1%of total death among cancers. Nepal being a developing country with poor socioeconomic and human development, the rate of lung cancer patient is in increasing trend. Tobacco smoking is one of the major risk factors causing 70% lung cancer deaths. The major objectives of the study was to find out association of cigarette smoking and relighting of cigarette butts while smoking with occurrence of lung cancer in Kathmandu Valley Nepal. Methods: An Unmatched Case Control study was conducted among 207 participants including 108 cases and 99 controls from the study areas; National Hospital and Cancer Research Centre Pvt. Ltd , Bhaktapur Cancer Hospital and areas nearby to the hospitals in Kathmandu from April 2017 to July 2017 purposively. For data collection interviewer administered questionnaire was used having Socio-demographic, Smoking Habits and Secondary Exposure to smoke characteristics section. Descriptive statistics was done to summarize the characteristics and analytical statistics was done in which bivariate analysis of factors showing pvalue <0.2 was included in the Multivariable Logistic regression where parsimonious model with backward regression was used to calculate odds ratios (ORs) and 95% confidence intervals to find association of risk factors. Results: In multivariate regression, cigarette smoking was a strong associated risk factor for occurrence of lung cancer (OR=1.91,95%C.I=1.001-3.66),even when adjusted with other 11 factors from the bivariate analysis (OR=2.85,95%C.I=1.054-7.68).Whereas relighting of cigarette butts while smoking showed positively strong association with occurrence of lung cancer when it was unadjusted (OR=4.47,95%C.I=2.28-8.78)as well as when adjusted for 17 factors from bivariate analysis (OR=37.63,95%C.I=7.55-187.46). Conclusions: As per this research smoking and relighting of cigarette butts were both major associated risk factors for occurrence of lung cancer. This call for strengthening the prevention aspect of tobacco control program to focus on behavioral change for reducing relighting of cigarette butts among the general population and also reducing tobacco addiction among the general population in Nepal.