Arterial Stiffness and Carotid Intima-Media Thickness in Children Exposed to Smokeless Tobacco in Fetal Life.

Abstract

Arterial stiffening and increased intima-media thickness can be seen as early as childhood and are associated with increased risk of cardiovascular events in adult life. The authors hypothesized that exposure to prenatal smokeless tobacco (Swedish snus) without additional nicotine exposure after the breastfeeding period would be associated with increased arterial stiffness and intima-media thickening in preschool children. This was a longitudinal follow-up cohort study of children aged 5 to 6 years exposed to high doses of nicotine in utero. Women exclusively using snus and unexposed controls were enrolled in early pregnancy (gestational age range, 6-12 weeks). Exposure data were collected during and after pregnancy with questionnaires from both groups. For this study, only children of women using >48 mg nicotine per day during their entire pregnancy were included in the exposure group. Outcomes were determined in 40 healthy children (21 exposed to snus in utero). Ultrasonography of the common carotid artery was used to determine carotid intima-media thickness and calculate arterial stiffness index from the relationship between pulsatile changes in arterial diameter and arterial pressure. Children exposed to snus in fetal life had higher carotid stiffness (median 4.1 [interquartile range (IQR), 2.4-5] versus 2.9 [IQR, 2.1-3.5]; P=0.014) than tobacco-free controls. Carotid strain (relative diameter change) was lower in children exposed to snus (mean 16% [SD, 5.7%] versus 21% [SD, 6.6%]) than in controls (P=0.015). Carotid intima-media thickness did not differ significantly between children exposed to snus and controls. Exposure to snus during fetal life was associated with a stiffer carotid artery in preschool children.