The association between albumin corrected calcium levels and mortality in ICU patients undergoing maintenance hemodialysis

While the relationship between albumin corrected calcium (ACC) levels and unfavourable outcomes has been previously investigated, existing studies have been limited in their specific application to patients undergoing maintenance hemodialysis (MHD) in intensive care unit (ICU). This retrospective cohort study aimed to explore the association between baseline ACC and 28-day in-hospital mortality in ICU patients undergoing MHD. Logistic regression model, smooth curve fitting, piecewise linear regression, subgroup analyses, and a series of sensitivity analyses were employed. Of the 2114 patients with a median age of 64 years, 290 (13.72%) died within 28 days after ICU admission. Multivariate regression analysis revealed that, in comparison with the lowest tertile, the highest tertile of ACC was associated with a higher mortality rate (OR 1.69, 95% CI 1.09-1.53, P = 0.0032). When the ACC levels were < 8.04 mg/dL, the mortality rate decreased with an adjusted OR of 0.44 (95% CI 0.20-0.98, P = 0.0438) for every 1 mg/dL increase in the ACC levels. When the ACC levels were ≥ 8.04 mg/dl, the mortality rate increased with an adjusted OR of 1.36 (95% CI 1.13-1.64, P = 0.0011) for every 1 mg/dl increase in the ACC levels. Non-linear relationship between ACC and 28-day in-hospital mortality were identified in patients undergoing MHD in the ICU. However, the findings of this study need to be confirmed through prospective studies.