L-arginine, Antioxidant Food Bar Reduces Pre-eclampsia

MEXICO CITYSupplementation during pregnancy with a medical food containing L-arginine and antioxidant vitamins reduced the incidence of pre-eclampsia in a population at high risk of the condition, according to a new study from American and Mexican researchers (BMJ 2011; 342:d2901 DOI: 10.1136/bmj.d2901). They found antioxidant vitamins alone did not have a protective effect for prevention of pre-eclampsia.

The randomized, blinded, placebo controlled clinical trial evaluated pregnant women with a history of a previous pregnancy complicated by pre-eclampsia, or pre-eclampsia in a first degree relative at a public hospital in Mexico City. The women, deemed to be at increased risk of recurrence of the disease, were studied from week 14 to 32 of gestation and followed until delivery. During pregnancy, the women received a medical food bars containing either L-arginine plus antioxidant vitamins (n=228), antioxidant vitamins alone (222) or placebo (222). Women had 4 to 8 prenatal visits while receiving the bars.

The incidence of pre-eclampsia was reduced by 12 to 21 percent (P<0.001) in women randomized to L-arginine plus antioxidant vitamins compared with placebo. Antioxidant vitamins alone showed an observed benefit (about 7 percent), but this effect was not statistically significant compared with placebo (P=0.052). L-arginine plus antioxidant vitamins were 9 percent more effective than antioxidant vitamins alone (P=0.004).

This study describes the first successful intervention resulting in prevention of pre-eclampsia providing a simple and inexpensive measure with potential use in public health," said lead researcher Felipe Vadillo-Ortega, M.D. L-arginine is the substrate for synthesis of nitric oxide, a compound with antihypertensive effects. Providing an extra amount of L-arginine in the diet of pregnant women at high risk for developing pre-eclampsia resulted in a protective effect against this disease," he said.

Jerome F. Strauss III, M.D., Ph.D., dean of the Virginia Commonwealth University School of Medicine who also authored the study, added: Nutritional interventions for the prevention of pre-eclampsia have been sought for some time. The medical food used in our study appears to offer substantial benefit for women at high risk of pre-eclampsia, demonstrating that nutritional supplementation is a viable and safe approach to prevention of a disease that is a major cause of maternal and neonatal  mortality.

According to Strauss and Vadillo-Ortega, the team will conduct further studies to determine whether these results are due to L-arginine alone, or a combination of L-arginine and antioxidant vitamins.