Low Male Birth Weight May Affect BP

A Swedish study shows that men bornwith below-average birth weight have aslightly higher risk of developing highblood pressure (BP) as young adults,compared with men born within the averageweight range.

The findings support the theory thatpoor fetal growth may cause metabolicdisorders, such as high BP or diabetes.This theory is known as the "fetal programminghypothesis," according to areport by Niklas Bergvall, PhD, of theKarolinska Institutet in Stockholm, whichappeared in the September 2005 issue ofEpidemiology.

Although past research has linked lowbirth weight (LBW) to high BP, most studieshave not taken socioeconomic andgenetic factors into account. Becauseboth are linked to the risk of LBW as wellas the risk of high adult BP, the relationshipcould be due to these factors.

The study included adult men, nearly90,000 of whom had at least 1 brother touse for a comparison. Because brothersshare an average of half their genes, growup in the same environment, and have thesame socioeconomic status, researcherswere able to control for the effect of thesefactors on the relationship between LBWand high BP.

The researchers defined LBW as aweight below 6 lb 3 oz for babies born at40 weeks' gestation, and high systolic BPas 140 mm Hg or higher. After adjustingfor genetic and socioeconomic factors,they found that men born with LBW had a14% greater risk of developing high BP inyoung adulthood.