Altered serum calcium homeostasis independently predicts mortality in patients with acute coronary syndrome: a retrospective observational cohort study

Abstract

ObjectivesSerum calcium levels (sCa) were reported to be associated with risk of cardiovascular diseases. The aim of this study was to analyse the association between sCa and long-term mortality in patients with acute coronary syndrome (ACS).DesignA retrospective observational cohort study.SettingSingle-centre study with participants recruited from the local area.ParticipantsA total of consecutive 13 772 patients with ACS were included in this analysis. Patients were divided based on their sCa profile (≤2.1 mmol/L, 2.1–2.2 mmol/L, 2.2–2.3 mmol/L, 2.3–2.4 mmol/L, 2.4–2.5 mmol/L,>2.5 mmol/L) and followed up for a median of 2.96 years (IQR 1.01–4.07).Primary outcomeLong-term all-cause mortality.ResultsDuring a median follow-up period of 2.96 years, patients with sCa ≤2.1 mmol/L had the highest cumulative incidences of all-cause mortality (16.7%), whereas those with sCa 2.4–2.5 mmol/L had the lowest cumulative incidences of all-cause mortality (3.5%). After adjusting for potentially confounding variables, the Cox analysis revealed that compared with the reference group (sCa 2.4–2.5 mmol/L), all the other groups had higher mortality except for the sCa 2.3–2.4 mmol/L group (HR, 1.32, 95% CI 0.93 to 1.87). Restricted cubic splines showed that the relationship between sCa and all-cause mortality seemed to be U shaped. The optimal sCa cut-off point, 2.35 mmol/L, was determined based on the shape of restricted cubic splines.ConclusionsAltered serum calcium homeostasis at admission independently predicts all-cause mortality in patients with ACS. In addition, a U-shaped relationship between sCa and all-cause mortality exists, and maintaining sCa at approximately 2.35 mmol/L may minimise the risk of mortality.

Association of admission serum calcium level with left ventricular dysfunction in patients with acute coronary syndrome

“…Previous studies investigated the correlation between serum calcium and left ventricular function and found that patients with low concentration of serum calcium were more likely to have LVEF < 50% ( 22 ). And patient with established heart failure presented low level of serum calcium concentration ( 13 , 23 ).…”

“…Serum calcium ions play a vital role in many metabolic and regulatory processes associated with cardiovascular disease, such as platelet adhesion and aggregation, blood coagulation, enzymatic activity, myocardial excitation, contraction and relaxation ( 8 , 9 ). In view of the roles of serum calcium in myocardial excitation-contraction coupling and cardiac electrophysiologic effect, abnormalities of serum calcium may cause disarrangement of calcium homeostasis in the cytoplasm of cardiomyocytes and lead to myocardial dysfunction ( 22 ). On the other side, hypocalcemia reduces renal sodium excretion ( 26 ), thus contributes to fluid overload and decreased myocardial contractility, as demonstrated by decreased left ventricular work index ( 9 , 27 ).…”

Non-linear relationship between albumin-corrected calcium and 30-day in-hospital mortality in ICU patients: A multicenter retrospective cohort study

“…The high mortality of ICU patients due to numerous risk factors, of which the disorders of electrolytes, including potassium, sodium, and calcium, is one of the most important risk factors (12). Previous studies have explored the association between serum calcium and mortality in different types of diseases (8,9,(13)(14)(15)(16)(17)(18)(19)(20). In Chinese patients with acute pulmonary thromboembolism, hypocalcemia (total serum calcium) is a risk factor of mid-and long-term mortalities (8).…”