Diarrhoea and smoking: an analysis of decades of observational data from Bangladesh.

BACKGROUND: Although cigarette smoking affects all biological systems of the human body including the gastrointestinal tract, there is a lack of evidence regarding its effect on the severity of diarrhoeal disease and whether a dose-response relationship exists. We therefore tested for the presence of specific causative pathogens for infectious diarrhoea, assessed the independent effect of smoking on its severity and tested whether any dose-response relationship existed while controlling for subjects' age, sociodemographic characteristics and presence of causative pathogens in an urban setting in Bangladesh. METHODS: A total of 20,757 patients aged 15 years and above with diarrhoea were enrolled into the Diarrhoeal Disease Surveillance System, managed by the International Centre for Diarrhoeal Disease Research, Bangladesh, from 1993 to 2012. We collected data on individuals' current daily consumption of cigarettes and bidis (traditional hand-rolled cigarettes) and conducted an ordered logistic regression to determine the effect of smoking on diarrhoeal disease severity and whether a dose-response relationship exists. RESULTS: We identified 19 % of patients with diarrhoea as smokers, of whom 52 % smoked 1-9 cigarettes per day. While 97 % of smokers were male, 41 % were aged 15-30 years of age. Smokers were found to have a significantly lower severity of diarrhoeal disease (OR: 0.92, 95 % CI: 0.85-0.99, p = 0.025) after adjusting for age, wealth quintile, illiteracy and the presence of specific causative pathogens (Vibrio cholerae and Shigella). We observed no dose-response relationship between the number of cigarettes smoked per day and disease severity when adjusting for the same covariates. Smokers were more frequently infected with Shigella (7 vs. 6 %, p < 0.001) and less often with Vibrio cholerae (22 vs. 26 %, p < 0.001) than their non-smoking counterparts. CONCLUSIONS: The aetiology and severity of diarrhoeal disease differed between smokers and non-smokers in our sample. However, we found no dose-response relationship between disease severity and the number of cigarettes smoked per day.

Association between paternal smoking and nutritional status of under-five children attending Diarrhoeal Hospital, Dhaka, Bangladesh.

AIM: The study aimed at determining whether there is an association between paternal smoking and nutritional status of children aged 0-59 months. Furthermore, the study looked at the presence of any nutritional differentials within different socio-economic groups. METHODS: Secondary analysis of data on children aged 0-59 months enrolled in the Hospital Surveillance System of International Centre for Diarrhoeal Disease Research, Dhaka Hospital, Bangladesh, during 1996-2006. RESULTS: Among 13,555 under-five children, fathers of 49% were smokers. In multivariate logistic regression models adjusting for potential confounders, fathers' smoking was significantly associated with increased risk of moderate underweight (OR 1.16, 95% CI 1.08-1.25), severe underweight (OR 1.15, 95% CI 1.06-1.26), moderate stunting (OR 1.15, 95% CI 1.06-1.23) and severe stunting (OR 1.13, 95% CI 1.03-1.25). In middle and lower socio-economic strata, risk of moderate and severe child malnutrition was found to be significantly increased in the group where the father was a smoker. CONCLUSION: Results indicate that there is an association between fathers' smoking and malnutrition of under-five children particularly in lower socio-economic group. A possible mechanism - if this association is causal - may be through a negative effect on family economy.