title: Calcium-to-creatinine ratio in spot urine samples in early pregnancy and its relation to the development of preeclampsia.
abstract: We investigated the relation between an alteration in calcium (Ca) excretion in early pregnancy and the risk of preeclampsia in 1,147 pregnant women. We measured Ca and creatinine (Cr) concentrations in spot urine samples obtained at 12 weeks or less of gestation. Seventy-one (6.2%) had hypertension alone, nine (0.8%) developed superimposed preeclampsia, 39 (3.4%) developed proteinuria alone, and 13 (1.1%) developed preeclampsia; 1,015 women did not develop hypertension or proteinuria. The Ca/Cr ratio was significantly reduced in the 39 women who eventually developed proteinuria (0.116 +/- .103) and 13 who developed preeclampsia (0.121 +/- .063) compared with 1,015 women who had neither hypertension nor proteinuria (0.158 +/- .239). The relative risk of development of preeclampsia, proteinuria, or superimposed preeclampsia was 1.98 (95% confidence interval, 1.22 to 3.22) for women with a Ca/Cr ratio less than the 30th percentile (0.082) compared with women with a Ca/Cr ratio greater than the 30th percentile. These results suggest that preeclampsia may be related, in part, to a relative Ca intake deficiency. Determination of the Ca/Cr ratio in spot urine samples in the first trimester is of only limited clinical value for identifying women with an increased risk of preeclampsia.
authors.affiliation: Department of Obstetrics and Gynecology, Jichi Medical School, Tochigi, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Izumi
authors.forename: H
authors.initials: H
authors.lastname: Minakami
authors.forename: T
authors.initials: T
authors.lastname: Kuwata
authors.forename: I
authors.initials: I
authors.lastname: Sato
mesh_terms: D015415:Biomarkers / Q000652:urine; D001794:Blood Pressure; D002118:Calcium / Q000652:urine*; D003404:Creatinine / Q000652:urine*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007564:Japan; D011225:Pre-Eclampsia / Q000453:epidemiology*; D011247:Pregnancy / Q000502:physiology / Q000652:urine*; D011249:Pregnancy Complications, Cardiovascular / Q000453:epidemiology; D011261:Pregnancy Trimester, First; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D003404:Creatinine; D002118:Calcium