Thursday, 21 October, 2021

Passive smoking causes heart disease in newborns

Passive smoking causes heart disease in newborns

Passive smoking by parents or others of family and outsiders is causing Congenital Heart Disease (CHD) or by-birth heart problems in children in Bangladesh, according to a study.

According to health experts, passive smoking means breathing in other people’s tobacco smoke. If a pregnant woman breathes in second-hand smoke, it can also affect the unborn baby. Second-hand tobacco smoke comes from cigarettes, pipes, cigars and shisha pipes (hookah).

There are two types of second-hand smoke--Mainstream smoke - smoke that’s breathed out by someone who smokes and side-stream smoke - smoke that comes from the lit end of a tobacco product, they added.

“Maternal active smoking is significantly associated with an increased risk of congenital heart defects (CHDs), but the association between maternal passive smoking and risk of CHDs is inconclusive,” Dr M. Abdullah Al Mamun, associate professor of Dhaka Shishu (Children) Hospital told the Daily sun.

A study was conducted to evaluate the effect of passive smoking and the risk of development of CHD among the Bangladeshi population. The study was conducted by Dr Abdullah Al Mamun along with Dr Md Khalid Ebna Shahid Khan and Prof Dr. Manzoor Hossain of the Dhaka Shishu Hospital (DSH).

The research was carried out from July 2018 to July 2019 in Paediatric Cardiology department of the DSH. It was published in the Malaysian Journal of Paediatrics and Child Health (MJPCH) on June 29 this year.

According to the study result, among case groups, no mother was active smoker while 51.9 percent were exposed to passive smoke and most of the cases source was husband,  19.6 percent took smokeless tobacco or green tobacco, 55.8 percent took tea and 5.8 percent took coffee during pregnancy period.

However, none of the mother was found smoker or alcoholic during the research, it added.

“Passive smoking was independently associated with CHDs. Mother with passive smoking exposure had 1.5 times risk of developing CHDs compared to those who were not exposed,” Abdullah Al Mamun said.

In the study, total 260 children having CHD was enrolled as cases and 280 children having no heart disease was taken as control. Among children, males were predominant in both groups. Most of the respondents were from rural area both in case (86.9 per cent) and control (80 per cent) group.

Dr Md Khalid Ebna Shahid Khan, also registrar of the department of Interventional Cardiology at the DSH, said passive smoking involves exposure to the same range of tobacco smoke toxins experienced by active smokers. Although at lower levels, it is likely that exposure to secondhand smoke also causes some or all of these complications but with lower levels of relative risk.

“Cigarette smoking contributes to the aetiology of CHD through induction of either male and female germ-cell mutation or interference with epigenetic pathways,” he added.

According to the study, all forms of tobacco use and exposure, including chewing tobacco and secondhand smoke, significantly increased health hazard as the timing and mechanism of this effect is not clear, it is important to prevent passive smoking exposure in women before and during pregnancy.

Active smoking among mothers in Bangladesh is low, while smoking prevalence among men is high, but the use of smokeless tobacco products is approximately the same among males and females, it added.

The study found that large number of mothers took smokeless or green tobacco even in their pregnancy period. It was not found statistically significant in the development of CHDs.

“Evidence suggests that although smokeless tobacco is less hazardous than smoked tobacco, there is indeed reason to be cautious about the use of smokeless tobacco,” Dr Mamun said.

Findings of the study also have shown that maternal smoking has adverse effects on the developing fetus, including hypoxia caused by carbon monoxide, nicotine and reduction in the supply of essential nutrients to the embryonic tissues.

“Although advancement in paediatric cardiology and paediatric cardiac surgery have improved long term outcome and promised better quality of life, the etiology of most congenital heart defects is still unknown,” Dr Md Khalid Ebna Shahid Khan, also a prominent pediatric cardiac surgeon said.

Clinicians and basic scientists have long understood the sources of these cardiovascular developmental errors, and there is wide acceptance of the opinion that the etiology of CHD is complex and possibly lies within the interaction of environmental exposures and inherited factors.

Khalid said maternal smoking during pregnancy tended to increase the risk of congenital heart defects.

The Global Adult Tobacco Survey (GATS) founds that the prevalence of male who smoked are far greater than female in Bangladesh (among males 45.6 per cent as compared to females 3.1 per cent). Use of smokeless tobacco products in Bangladesh was approximately the same among males (26.4 per cent) and females (27.9 per cent).

According to the observation of the research, this has made it difficult to create population-based strategies to reduce the burden of illness from CHDs and for couples to choose lifestyles to reduce the risk of delivering a child with CHDs. This study was therefore performed to investigate the effect of passive smoking on the risk of developing CHD in the Bangladesh population.