Additional birth weight cuts risk of developing TB: Study

According to Eduardo Villamor,study author and associate professor at the U-M School of Public Health,the association between birth weight and developing disease is much stronger for males than females.

Girls are 16 per cent less likely to develop TB for every 1.1 pounds of birth weight,while the risk decreased by 87 per cent for infant males with each pound,he said.

“It’s too early to say if insufficient prenatal growth causes clinical tuberculosis,but the findings suggest that may be the case,” Villamor said.

“The fact that researchers studied twins and could control for many genetic and environment factors that influence the development of TB supports the causal relationship.”

Villamor and his team worked at the Karolinska Institute in Sweden and began the research while at Harvard.

The findings are important because tuberculosis infects about one-third of the planet’s population,and is second only to HIV in deaths caused by a single infection. Low birth weight of babies is a larger problem in developing countries,but it occurs everywhere,he said.

“The study also helps understand the developmental origins of health and disease,” Villamor said,which is an emerging field.

“Prenatal exposure to environmental insults,including maternal malnutrition,could program what happens later on in terms of our immune responses to infection,possibly through programming of the immune system,” he said.

“This study is an example of that.”

The study,”Evidence for an effect of fetal growth on the risk of tuberculosis,” is set to appear in the next edition of the Journal Infectious Disease.