Prevalence and Etiological Profile of Hypercalcemia in Hospitalized Adult Patients and Association with Mortality.

Background: The etiology of hypercalcemia varies according to the clinical setting. Hitherto, data on the prevalence and profile of hypercalcemia in hospitalized Asian-Indian patients are limited. Hence, we conducted a prospective observational study to determine the prevalence and etiological profile of hypercalcemia in hospitalized Asian-Indian patients and its association with 6-month mortality. Materials and Methods: We conducted a prospective observational study wherein all the patients (aged >12 years) admitted to the general medicine wards of a tertiary care hospital in North India between January 1, 2016, and June 30, 2017, were screened. Finally, patients with sustained hypercalcemia (defined as corrected serum total calcium ≥10.4 mg/dl documented twice at least 24 h apart) were included in this study. These patients were followed up throughout the hospital course and thereafter till 6 months from the date of discharge. Results: Out of 9902 patients, 150 patients had sustained hypercalcemia (prevalence 1.5%). The most common cause of hypercalcemia was malignancy (41.3%), followed by primary hyperparathyroidism (PHPT, 32.7%). Vitamin D intoxication was responsible for hypercalcemia in 8.7% of patients; 2.7% of patients had hypercalcemia of advanced chronic liver disease. Nevertheless, a definite etiology could not be identified in 7.3% of the patients with hypercalcemia. At the end of 6 months of follow-up, the cumulative mortality rate was 28%. Underlying malignancy and higher calcium levels were the significant determinants of mortality. Conclusions: The prevalence of hypercalcemia in Asian-Indian patients admitted to a tertiary care hospital was 1.5%. The most common etiology was malignancy, followed by PHPT.