Parents who smoke are increasing their children’s risk for carotid atherosclerosis, found one study published online March 23 in Circulation. Researchers noted while markers remained, those who practiced good hygiene and avoided their children when smoking reduced some of that risk.

The Cardiovascular Risk in Young Finns study compared carotid ultrasound and childhood serum cotinine levels acquired in either 1980 or 1983 to those from 2001 or 2007. At baseline, parents noted whether one or both smoked. Children were ages three, six, nine, 12, 15 or 18 years at baseline.

The overall analysis by Henry W. West, BM, of Menzies Institute for Medical Research at the University of Tasmania in Hobart, Australia, and colleagues included 2,448 patients. They performed a subanalysis of serum cotinine on 1,578 participants.

Risk for detected adulthood carotid plaque among children of smokers was nearly double that of nonsmokers (1.7). However, smoking hygiene had a significant influence on reducing some of the risk for detectable carotid artery plaque. Children whose parents did not smoke around them had 1.6 times more risk for plaque than those of nonsmokers. Children whose parents smoked in their presence had four times the risk of children whose parents didn’t smoke.

Parental smoking had significant impacts on the number of children with nondetectable serum cotinine. Among children whose parents did not smoke, 84 percent had no detectable cotinine. Among children whose parents smoked with nondetectable cotinine, 62 percent had one parent who smoked and 43 percent, both parents smoked.

West et al noted that overall the influence of parental smoking was the greatest among the youngest children. Those who were three to nine at baseline were 6.3 times more likely to have increased plaque more than years later.

The research team stressed that for increased benefits to children, smokers should quit, but if they cannot, “[parents] may be able to reduce some of the potential long-term risk for their children by actively reducing their children’s exposure to secondhand smoke (i.e., not smoking inside the home, car, or smoke well away from their children),” said senior author Costan Magnussen, PhD, also of the Menzies Institute for Medical Research and of the University of Turku in Finland in a press release.