Reduced Blood Circulating Calcium Level Is An Outstanding Biomarker For Preeclampsia Among 48 Types Of Human Diseases.

Abstract

BACKGROUND\nCalcium ion (Ca2+) is essential for human physiology by regulating various signal transduction pathways inside all cells and in the blood circulation.\n\n\nAIM\nWe compared circulating Ca2+ levels in the healthy control against 48 different types of human diseases.\n\n\nDESIGN\nA total of 144,201 independent test results of Ca2+ levels from 48 clinically defined diseases and 141,679 independent test results of Ca2+ from healthy individuals who came to the hospital for annual physical examination were retrieved during the past five years.\n\n\nMETHODS\nCa2+ was determined by the standard Arsenazo III method in the clinical laboratory of Affiliated Hospital of Qingdao University. We analyzed all data using RStudio V.1.3.1073 and python libraries 3.8.\n\n\nRESULTS\nAll 48 types of diseases had decreased Ca2+ levels than the healthy control based on either mean or median values. Patients suffering from preeclampsia had the lowest Ca2+ levels among all 48 diseases. The perfect AUC, sensitivity, and specificity values of 1.0, 0.96, and 0.96 indicated that Ca2+ was an excellent biomarker for diagnosing preeclampsia. Extremely low Ca2+ was present in patients suffering kidney-related diseases. Since the correlation between each disease on the statistical features is proportional to their vector distance, the two-component analysis revealed that preeclampsia, sepsis, and chronic obstructive pulmonary disease were closely related among 48 diseases.\n\n\nCONCLUSIONS\nAll human diseases were associated with reduced circulating Ca2+ levels, where the decreased Ca2+ was a perfect biomarker for preeclampsia. Kidney-related conditions were related to over-down-regulation of Ca2+ levels. The resemblance of preeclampsia to sepsis and chronic obstructive pulmonary disease based on two-component analysis suggested that the three unrelated diseases might share a similar mechanism of the circulating Ca2+ regulation.