Calcium and conjugated linoleic acid reduces pregnancy-induced hypertension and decreases intracellular calcium in lymphocytes

Background: The aim of the present study was to determine whether the beneficial effect of oral supplementation with calcium and conjugated linoleic acid (CLA) in the reduction of the incidence of pregnancy-induced hypertension (PIH) is related with changes in plasma levels of prostanoids, renin, angiotensin II, calciotropic hormones, and plasma and intracellular ionized free calcium. Methods: These mediators were determined using the blood samples obtained from a randomized, double-blind, placebo-controlled trial that included 48 healthy primigravidas with a family history of preeclampsia and with diastolic notch, recruited from four outpatient clinics from two developing countries. Participants were randomized to daily oral doses of elemental calcium and CLA or lactose-starch placebo from week 18 to week 22 of gestation until delivery. Results: The incidence of PIH was significantly reduced in women receiving the supplement (2 women [8.3%]) compared with placebo (10 women [41.7%]) (relative risk = 0.20, 95% confidence interval 0.05-0.82, P = .01). There were no significant differences in the plasma concentrations of ionized calcium, prostaglandin E-2, renin, angiotensin II, parathormone,and calcitonine. The concentration of intracellular ionized free calcium presented a significant reduction after interventions (92.0 nmol/L [range 62.5 to 220 nmol/L] nu 62.5 nmol/L [range 28 to 200 nmol/L; P = .01) in the supplemented group but not in the placebo group. The women who developed PIH (n = 12) presented a significant increase in the concentrations of intracellular calcium after interventions (120 nmol/L [range 89.2 to 240 nmol/L] nu 137.5 nmol/L [range 89.2 to 138 nmol/L; P = .02). Conclusions: Calcium and CLA supplementation during pregnancy reduces the incidence of PIH, and decreases the intracellular concentration of ionized free calcium in peripheral blood lymphocytes. (c) 2006 American Journal of Hypertension, Ltd.