Low birth-weight possible risk for hypertension in adulthood - Geriatric Nutrition - Brief Article

Nutrition Research Newsletter, Nov, 2001

The intrauterine environment is thought to possibly play a crucial role in the development of hypertension later in life. Previous studies have shown a relationship between low birth weight and elevated blood pressure (BP) in adult life. This relationship has been studied in twins as twin studies afford an opportunity to distinguish between individual fetoplacental, maternal, and genetic influences.

Researchers investigated the association between birth weight and adult resting ambulatory BP in young adult twins. The subjects consisted of 418 twin pairs between 18 and 34 years of age who were randomly selected from the East Flanders Prospective Twin Survey. The East Flanders Prospective Twin Survey is a population-based survey that that prospectively registered all twins born in the Belgian Province of East Flanders since 1964. Subjects were excluded if they suffered from cardiovascular disease, endocrine disorders. or multiple sclerosis or were taking drugs with potential effects on BP. Birth weights were obtained from obstetric records. The obstetrician reported gestational age. All subjects visited the research center for a two-hour examination in the morning. Following five minutes of a supine rest. BP was measured on the right arm in triplicate by sphygmomanometry and auscultation. Body mass index was calculated after obtained standing height and weight. Ambulatory BP was monitored using the SpaceLabs 90207 device. Subjects wore the monitor at home on the nondominant arm for 24-hour duration. They were instructed to perform normal activity, but not to engage in vigorous physical exercise.

In women, it was found that resting systolic blood pressure decreased 4.27 mm Hg (P<0.001) and diastolic pressure decreased 2.18 mm Hg (P=0.02) kilogram increase in birth weight. Similar associations were seen in ambulatory measurements, however they were less significant. Twin pairs of whom both siblings had a low birth weight had a higher systolic blood pressure compared with twins who both had a high birth weight. The results were similar for monozygotic and dizygotic twin pairs. There were no associations found between birth weight and adult blood pressure in men.

It appears that prenatal programming of adult blood pressure occurs in female twins. The researchers suggest that maternal influences, experienced by both twin siblings, may be the precipitating association between birth weight and blood pressure. The association seems to be most pronounced when both fetuses had low birth weight. Further investigation is needed to clarify this association.

R. Loos, R. Fagard, G. Beunen, et al. Birth weight and blood pressure in young adults. Circulation 104: 1633-1640 (October, 2001) [Correspondence: Ruth Loos, Faculteit voor Lichamelijke Opvoeding en Kinesitherapie. Tervuursevest 101, B-3001 Leuven, Belgium. E-mail: ruth.loos@med.kuleuven.ac.be.]