Predictive Impact of Electrolyte Abnormalities on the Admission Outcome and Survival of Palliative Care Cancer Referrals

Background and Aim: Electrolyte abnormalities are common among patients with advanced cancer. Our aim was to estimate the prognostic significance of such abnormalities in a palliative care setting. Methods: A retrospective review of the medical records of inpatients with cancer referred to palliative care over a 25-month period. The five electrolytes studied were potassium, sodium, calcium, magnesium, and phosphate. The prognostic impact of related abnormalities on admission outcome and overall survival was estimated in univariate analysis. Results: From 866 new cancer referrals, 259 (30%) were eligible for analysis. Abnormalities in sodium, calcium, and magnesium levels were associated with a significant difference in inpatient death rates (p = 0.004, 0.001 and 0.04, respectively) and overall survival (p = 0.0008 and 0.0008, and < 0.0001, respectively). The status of potassium and phosphate had no significant impact on admission outcome or overall survival. The three electrolyte abnormalities associated with the highest inpatient death rate were hypercalcemia, hypernatremia, and hypermagnesemia (69%, 68%, and 62%, respectively). Patients with these abnormalities had the shortest median survival as well (12, 8, and 12 days, respectively). Conclusion: Some electrolyte abnormalities may be useful as prognostic indicators in the palliative care setting. However, their prognostic value needs to be investigated in prospective studies and adjusted against proven prognostic indicators.