Association of hypocalcemia with in-hospital mortality and complications in patients with acute pulmonary embolism: results from the 2017 Nationwide Inpatient Sample

Background Acute pulmonary embolism (PE) is a common cause for hospitalization associated with significant mortality and morbidity. Disorders of calcium metabolism are a frequently encountered medical problem. The effect of hypocalcemia is not well defined on the outcomes of patients with PE. We aimed to identify the prognostic value of hypocalcemia in hospitalized PE patients utilizing the 2017 Nationwide Inpatient Sample (NIS). Methods In this retrospective study, we selected patients with a primary diagnosis of Acute PE using ICD 10 codes. They were further stratified based on the presence of hypocalcemia. We primarily aimed to compare in-hospital mortality for PE patients with and without hypocalcemia. We performed multivariate logistic regression analysis to adjust for potential confounders. We also used propensity-matched cohort of patients to compare mortality. Results In the 2017 NIS, 187,989 patients had a principal diagnosis of acute PE. Among the above study group, 1565 (0.8%) had an additional diagnosis of hypocalcemia. 12.4% of PE patients with hypocalcemia died in the hospital in comparison to 2.95% without hypocalcemia. On multivariate regression analysis, PE and hypocalcemia patients had 4 times higher odds (aOR-4.03, 95% CI 2.78-5.84, p < 0.001) of in-hospital mortality compared to those with only PE. We observed a similarly high odds of mortality (aOR = 4.4) on 1:1 propensity-matched analysis. The incidence of acute kidney injury (aOR = 2.62, CI 1.95-3.52, p < 0.001), acute respiratory failure (a0R = 1.84, CI 1.42-2.38, p < 0.001), sepsis (aOR = 4.99, CI 3.08-8.11, p < 0.001) and arrhythmias (aOR = 2.63, CI 1.99-3.48, p < 0.001) were also higher for PE patients with hypocalcemia. Conclusion PE patients with hypocalcemia have higher in-hospital mortality than those without hypocalcemia. The in-hospital complications were also higher, along with longer length of stay.