Prognostic value of hypercalcemia in COVID‐19 infection: Retrospective cohort study

Abstract Purpose An increased incidence of hypercalcemia and the proposed prognostic value of calcium have been reported in patients with COVID‐19. We analyzed demographics, calcium levels, laboratory values, and clinical outcomes to determine the impact of calcium levels on survival. Method Information on 7927 adults admitted from 1/2/2022 to 31/3/2022 to three regional hospitals in Hong Kong was retrospectively collected. Of these, 1886 patients had confirmed COVID‐19. Results Hypercalcemia prevalence in COVID‐19 patients was 7.42% compared to 7.64% in other medical conditions ( p = 0.761). Median calcium levels were lower in the COVID‐19 group (2.36 mmol/L vs. 2.39 mmol/L, p < 0.001). Median calcium in patients who died was 2.41 mmol/L, compared to 2.35 mmol/L in survivors ( p < 0.001). Adjusted OR for calcium level was 4.419 (95% CI: 1.290–15.144, p = 0.018). Conclusion Hypercalcemia was associated with higher mortality in COVID‐19 infection. But COVID‐19 infection did not exhibit a higher incidence of hypercalcemia compared to other acute medical conditions.