Preeclampsia linked with later kidney problems

Pregnant women who develop preeclampsia and who have a low birth weight infant appear to have an increased risk of later kidney problems, according to an online report in the Journal of the American Society of Nephrology. The risk of kidney disease is highest in women with both factors.

Preeclampsia is a complication of pregnancy characterized by elevated blood pressure and protein in the urine that occurs after the 20th week.

"It is well known that preeclampsia is associated with later cardiovascular disease in the mother," lead author Dr. Bjorn Egil Vikse, from the University of Bergen in Norway, said in a statement.

"Our study is the first to document a strong relationship between preeclampsia and low birth weight offspring and later clinical kidney disease in the mother."

To evaluate the link between pregnancy outcomes and kidney disease, the researchers correlated data from a Norwegian birth registry with that from a kidney biopsy registry. The study included 756,420 women, of whom 588 underwent kidney biopsy an average of 15.9 years after the birth of their child.

Preeclampsia and having a low birth weight infant, either alone or in combination, was tied to an elevated risk of kidney biopsy. Moreover, the risk of kidney disease increased as infant birth weight decreased.

Vikse said his team expected to find preeclampsia and low birth weight were associated with the development of kidney disease, but were surprised at the strength of the associations. Also, they were surprised that pregnancy outcome predicted future kidney disease in general, and not just a specific type, he added.

The development of preeclampsia and kidney disease may involve similar mechanisms, Vikse said, adding that further studies are needed to determine if it would be worthwhile, from a public health standpoint, to screen women with a preeclampsia history for kidney disease.

SOURCE: Journal of the American Society of Nephrology, January 18, 2006.