Early weight gain linked to higher blood pressure in adulthood

The pace of weight gain in early childhood may be associated with increased blood pressure in adulthood, according to a report by researchers at Bristol University. The findings were published in October's edition of Hypertension: Journal of the American Heart Association.

The study is the first to examine whether accelerated infant growth predicts adult systolic and diastolic blood pressure. Systolic blood pressure is the pressure in the arteries while the heart contracts. Diastolic blood pressure is the pressure when the heart relaxes between beats. 

Researchers found that:

• Babies that are lighter at birth have higher systolic blood pressure as adults.
• Babies that gain weight more rapidly in the first five months after birth and from about ages 2 to 5 years have higher systolic blood pressure in young adulthood.
• Immediate weight gain after birth is associated with higher adult diastolic blood pressure.

Yoav Ben-Shlomo, lead author and Professor of Clinical Epidemiology in the University's Department of Social Medicine, said: "Changes in immediate (or the first five months) post-natal weight gain and childhood weight gain were associated with small changes in systolic blood pressure that were probably not due to chance.

"At an individual level, these changes would not be very important but in public health terms they are relevant."

The researchers followed 679 adults (about age 25) whose growth patterns were tracked as infants as part of the Barry Caephilly Growth Study. Measurements had been recorded at 14 points between birth and age five.

After studying whether subjects' growth patterns influenced blood pressure into adulthood, they found that weight gain occurring between 0 and five months and one year, and nine months to five years made the most difference.

Professor Ben-Shlomo added: "When trying to understand why some people get high blood pressure in later life, we need to consider a life course approach that considers early life as well as adult life risk factors such as dietary salt and obesity.

"For example, two babies are born of average weight, both on the 50th percentile of the birth weight distribution. One of them gains weight but remains within the 50th percentile, while the other gains weight more rapidly and is on the 85th percentile when both are 6 months old.

"Our study suggests that the second baby would have higher systolic blood pressure at age 25 (after adjusting for other factors such as how much they weighed at birth or 5 years, smoking, adult obesity, and so on) than the other baby who stayed where he was on the distribution."

The study helps researchers understand what drives the increase in average blood pressure that, as we age, results in a greater risk of high blood pressure or hypertension.

He added: "From a public health perspective, the results are important. If children put on more post-natal weight today than they did in the past, then we could better predict that the burden of high blood pressure will increase in the future. Hypertension, in turn, is associated with an increased risk of heart disease and stroke."

Paper: 'Immediate Postnatal Growth is Associated with Blood Pressure in Young Adulthood' by Yoav Ben-Shlomo, Anne McCarthy, Rachael Hughes, Kate Tilling, David Davies, and George Davey Smith.

The study was funded by the British Diabetic Association and the British Heart Foundation.

http://www.bris.ac.uk