Smoking during pregnancy has minimal effect on CV risk factors in offspring
MedWire News: Study findings suggest that maternal smoking during pregnancy has little effect on cardiovascular (CV) risk factors in offspring in early adulthood.
"The only evidence that maternal smoking is associated with the development of metabolic CV risk factors in early adulthood was the observation that high-density lipoprotein (HDL) cholesterol was lower among offspring of smokers," write Bernardo Lessa Horta (Universidade Federal de Pelotas, Brazil) and team in the journal Atherosclerosis.
Exposure to maternal smoking during pregnancy has been associated with short and long-term health risks, they explain. However, evidence concerning the programming of CV diseases by maternal smoking during pregnancy is limited, and evidence on the long-term effects of smoking during pregnancy on offspring is restricted to observational studies.
The team therefore performed a follow-up analysis on a Brazilian birth cohort recruited in 1982. The study included a total of 5914 mothers who were asked during an interview whether they had smoked during their pregnancy.
From October 2004 through August 2005 the researchers identified 4297 of the children from the cohort and assessed several metabolic risk factors for CV disease, namely blood pressure, HDL cholesterol, triglycerides, blood glucose, and C-reactive protein.
Overall, 64.5% (n=2765) of the mothers said they did not smoke during their pregnancy, 8.1% (n=348) said they stopped smoking during their pregnancy, and 27.4% (n=1176) smoked throughout their pregnancy.
The researchers report that of the CV risk factors assessed, the only outcome associated with maternal smoking was HDL cholesterol in females. Indeed, women born to mothers who smoked during pregnancy had significantly lower HDL cholesterol levels at 23 years of age than those who did not smoke, at 57.5 mg/dl (1.49 mmol/l) versus 60.4 mg/dl (1.56 mmol/l).
These findings remained significant after controlling for possible confounding variables, such as perinatal factors (low birth weight and preterm births), adult behavioral factors (physical activity, dietary pattern, intake of fat and fiber, and tobacco smoking), and adult anthropometry (body mass index and waist circumference).
The researchers conclude, therefore, that previously reported associations between maternal smoking and risk factors for CV disease in adulthood are likely due to postnatal exposure to lifestyle patterns.
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By Nikki Withers