A UNIVERSITY of WA study has found the risk of heart disease is greater among teen girls who smoke or take the oral contraceptive pill (OC), compared to teen boys who smoke.
Published in the Journal of Lipid Research, researchers surveyed 1050 teenagers from the Western Australian Pregnancy Cohort (Raine) Study featuring children born between 1989 and 1992. They analysed the data of adolescents who attended a 17-year review.
It follows on from their previous work, published in The Journal of Clinical Endocrinology and Metabolism last year, which found teen girls had a greater heart disease risk than teen boys when exposed to passive smoking.
Lead author Dr Chi Le-Ha, from UWA's School Medicine and Pharmacology and based at Royal Perth Hospital, says girls who smoked and didn’t use OCs had significantly higher high-sensitivity levels of C-reactive protein (CRP), which has been linked to cardiovascular disease.
“On the other hand, the group that used OCs but did not smoke also had higher high-sensitivity CRP levels,” he says.
“Studies in adults previously have shown that smoking or OC use is independently associated with higher CRP.
“Interestingly in our study, the group of girls that both smoke and use OCs was not significantly associated with higher high-sensitivity-CRP. This may be due to the anti-oestrogenic effects of smoking.”
The group of boys who smoke also had higher CRP, although the association was not statistically significant.
As CRP is an inflammatory marker, both smoking and OC use adversely affect the body’s inflammatory profile.
“Both active and passive smoking are important modifiable cardiovascular risk factors,” Dr Le-Ha says.
“We found that adolescent girls are vulnerable to the harmful effects of active and smoking exposure with regard to future cardiovascular disease risk.”
Dr Le-Ha says the study’s findings support CRP’s important role in predicting this risk, particularly in women.
“Abandoning smoking and banning smoking in public places have been crucial points in cardiovascular health promotion programs,” he says.
“In this context, our research suggests the effects of smoking exposure on long-term cardiovascular health may be more detrimental in women, given both smoking behaviour and C-reactive protein levels track from childhood to adulthood.”
While the research again endorses a no-smoking lifestyle is better for health, there is also concern about OCs increasing blood pressure.
Dr Le-Ha and his team have previously reported on the issue highlighting the need for female teens to modify behaviours to help prevent adult hypertension.