Cardiovascular impact of tobacco smoke exposure in pediatrics
Examining the current burden of tobacco smoke exposure, its associated cardiovascular health risks to our pediatric population, and what we can do to make a difference.
Primary Author: Charles Spear, MD | Chief Pediatric Resident
Column Editor: Rupal Gupta, MD | Medical Director, Operation Breakthrough Clinic | General Academic Pediatrics | Assistant Professor, UMKC School of Medicine
Over the greater part of the last half-century, there has been a heightened awareness of the negative health risks associated with tobacco product use. In addition to the risks associated with direct use of tobacco and nicotine, we now know more about the effects of tobacco smoke exposure on the cardiovascular health of children. This includes the immediate consequences of secondhand smoke exposure, as well as the adverse cardiovascular effects that persist into adulthood. Evidence points to tobacco smoke exposure as a major proponent of cardiovascular morbidity and mortality in children. Providers need to convey these risks to families, who may not understand the prevalence of tobacco exposure and its adverse effects on child health.
Although the prevalence of adult smokers declined from 20.9 percent in 2005 to 15.1 percent in 2015, children continue to be disproportionately affected by environmental tobacco smoke. Indeed, among the 58 million non-smokers in the U.S. exposed to tobacco smoke, approximately 40 percent of these exposures occurred in children, with an estimated 15 million between the ages of 3 and 11 years, and 9.6 million between 12 and 19 years of age.1 Furthermore, a 2013 study demonstrated that among the adolescent population itself, nearly six in 10 U.S. middle and high school students reported exposure to tobacco smoke.2 Other epidemiological factors play a role in increasing the burden of exposure, including racial disparities, socio-demographic differences, living environment (such as living in multi-unit housing), and most importantly, whether or not parents in the household smoke. In fact, a 2014 systematic review concluded that parental smoking is the strongest predictor of childhood environmental tobacco exposure when compared to other positive predictors of exposure.3 This exposure occurs through both secondhand and thirdhand smoke. Secondhand smoke is the combination of gases and fine particles emitted from a tobacco product that a non-user inhales directly, while thirdhand smoke represents the exhaled particulate that sticks to surfaces and can expose a non-user through both skin contact and inhalation over long periods of time.
The cardiovascular effects of secondhand smoke exposure on children include its association with obesity, dyslipidemia and elevated blood pressure. Indirect tobacco smoke exposure starts in utero, and studies have shown that compared to children of nonsmoking mothers, those offspring with in utero exposure have an increased risk of obesity by age 4 years old.4 Smoking during pregnancy is also linked to a significantly lower high density lipoprotein (HDL) level in children.5 Further evidence points to higher measured systolic and diastolic blood pressures of pre-school children exposed to environmental tobacco smoke compared to their peers.6 When combined with other atherosclerosis-promoting risk factors, these comorbidities can in turn lead to premature cardiovascular disease in a child or adolescent.7
Preventing environmental smoke exposure can help prevent the cardiovascular effects that a child might experience in adulthood, and this is where we as general pediatricians can make an impact. In its 2015 Public Policy to Protect Children from Tobacco, Nicotine and Tobacco Smoke, the American Academy of Pediatrics (AAP) emphasized that no safe level of tobacco smoke exposure exists.8 A recent meta-analysis found that parental interventions with statistically significant benefit in increasing parental cessation rate had several unifying qualities: They were geared toward parents of children aged 4 years and older; they utilized a cessation medication in their intervention; they included interventions whose primary purpose was cessation; lastly, they had high rates of established follow-up with families.9
While smoking cessation is the optimal choice, physicians can start the conversation by encouraging parents to keep the home and car smoke-free. This simple intervention has high potential for effectiveness: among adolescents, lack of smoke-free rules at home was associated with a nine-fold increase in risk of exposure to environmental tobacco smoke.2 Pragmatically, some recommend that parents utilize a smoking jacket that is stored outdoors, but trials have not yet been done to examine the degree to which harm-reducing strategies such as this may help reduce children’s environmental smoke exposure.
Ultimately, evidence-based policy actions will be essential to help decrease tobacco smoke exposure among children.8 However, it is our job in supporting the AAP’s efforts and ultimately, the children we serve, to arm ourselves with the knowledge of the negative consequences of tobacco exposure among our youth and to share this information with families.
Vital Signs: Disparities in Nonsmokers' Exposure to Secondhand Smoke - United States, 1999-2012. Homa DM, Neff LJ, King BA, Caraballo RS, Bunnell RE, Babb SD, Garrett BE, Sosnoff CS and Wang L. MMWR Morbidity and mortality weekly report. 2015;64:103-8.
Prevalence and Determinants of Secondhand Smoke Exposure Among Middle and High School Students. Agaku IT, Singh T, Rolle I, Olalekan AY, King BA. Pediatrics. 2016;137(2).
Predictors of Children's Secondhand Smoke Exposure at Home: A Systematic Review and Narrative Synthesis of the Evidence. Orton S, Jones LL, Cooper S, Lewis S and Coleman T. PLoS One. 2014;9:e112690.
Parental Smoking During Pregnancy, Early Growth, and Risk of Obesity in Preschool Children: The Generation R Study. Durmus B, Kruithof CJ, Gillman MH, Willemsen SP, Hofman A, Raat H, Eilers PH, Steegers EA and Jaddoe VW. The American Journal of Clinical Nutrition. 2011;94:164-71.
Maternal Cigarette Smoking is Associated with Reduced High-density Lipoprotein Cholesterol in Healthy 8-year-old Children. Ayer JG, Belousova E, Harmer JA, David C, Marks GB and Celermajer DS. European heart journal. 2011;32:2446-53.
Determinants of Blood Pressure in Preschool Children: The Role of Parental Smoking. Simonetti GD, Schwertz R, Klett M, Hoffmann G, Schaefer F, Wuhl E. Circulation. 2011; 123:292-8.
Exposure to Parental Smoking in Childhood is Associated with Increased Risk of Carotid Atherosclerotic Plaque in Adulthood: The Cardiovascular Risk in Young Finns Study. West HW, Juonala M, Gall SL, et al. Circulation. 2015;131:1239–46.
Section on Tobacco Control. Public Policy to Protect Children From Tobacco, Nicotine, and Tobacco Smoke. Pediatrics. 2015; 136(5): 998-1007.
Parental Smoking Cessation to Protect Young Children: A Systematic Review and Meta-analysis. Rosen, LJ, Noach MB, Winickoff JP, Hovell MF. Pediatrics. 2012; 129(1): 141-152.