Selenium, zinc and copper plasma levels in intrahepatic cholestasis of pregnancy, in normal pregnancies and in healthy individuals, in Chile

Background/Aims: Low blood Se levels have been previously shown in normal p regnancies (third trimester) and significantly lower levels in patients wit h intrahepatic cholestasis of pregnancy (ICP), in Finland and in Chile, sug gesting that a low or marginal dietary availability of Se may contribute to the pathogenesis of this disease. The aim of this study was to investigate whether a temporal change in plasma concentration of Se, and seasonal fluc tuations in plasma concentrations of Se, Zn and Cu, could coincide with cha nges in the prevalence of ICP. Methods: A cross-sectional cohort study was done including 21 ICP patients, 98 women in the third trimester of a normal pregnancy, 29 non-pregnant wom en, and also 13 individuals (seven non-pregnant women and six men) who had been studied 9 years before. Plasma Se, Zn and Cu were measured by atomic s pectroscopy. Plasma Se levels in the present study were compared to the res ults obtained 5 to 7 years before, employing identical methodology in simil ar population samples. Results: Plasma Se concentrations in non-pregnant women were higher than in the previous study: 1.43+/-0.34 mu mol/l ps 0.85+/-0.13; p<0.001. In compa rison to non-pregnant women, normal pregnancies near term had lower plasma levels of Se: 1.08+/-0.25 mu mol/l; p<0.01, and Zn: 17.90+/-3.61 mu mol/l I ts 19.71+/-3.21; p<0.05, but higher plasma Levels of Cu: 34.35+/-7.12 mu mo l/l vs 20.62+/-3.34; p<0.01. In normal pregnancies, plasma Se concentration was significantly higher in summer (1.34+/-0.19 mu mol/l) than in the othe r seasons, while Zn and Cu diminished. Similar to previous studies, ICP pat ients had significantly lower Se plasma levels than normal pregnancies: 0.9 4+/-0.12 mu mol/l, p<0.05, and Cu levels were significantly higher: 50.80-c 7.02 mu mol/l, p<0.01. Cu plasma levels correlated with the biochemical sev erity of the disease. Zn did not change in ICP. Conclusions: The present study shows that the decrease in the prevalence of ICP in Chile during the last decade coincides with an increase in plasma S e levels. Its lower incidence during summer coincides with a higher plasma Se concentration in summer than in other seasons, as observed in normal pre gnancies.