Research Information System
European Journal of Geriatrics and Gerontology, vol.7, no.2, pp.59-70, 2025 (Scopus)
Objective: Hypophosphatemia is a critical condition in intensive care settings, often linked to adverse clinical outcomes. Elderly patients, due to factors such as malnutrition, comorbidities, and altered renal function, are vulnerable to this condition. This study aimed to evaluate the incidence, associated factors, and clinical implications of hypophosphatemia in elderly critically ill patients. Materials and Methods: A retrospective cohort study was conducted in a tertiary intensive care unit (ICU) between January 2020 and December 2022. Patients aged ≥65 years were divided into two groups: hypophosphatemic and non-hypophosphatemic. Hypophosphatemia was defined as a serum phosphate level <2.5 mg/dL. Results: Among 433 elderly critically ill patients, the incidence of hypophosphatemia was 18.5%. Logistic regression analysis identified cardiac decompensation as the reason for ICU admission [odds ratio (OR): 2.33, 95% confidence interval (CI): 1.09-4.95, p=0.028]; absence of renal injury according to the Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) classification (OR: 3.83, 95% CI: 2.19-6.71, p<0.001); hypokalemia (OR: 2.61, 95% CI: 1.46-4.69, p=0.001); and hypoalbuminemia (OR: 2.61, 95% CI: 1.46-4.67, p=0.01) as independent risk factors for hypophosphatemia. Subgroup analysis revealed a higher prevalence of hypophosphatemia of 32.8%, in patients without renal injury according to the RIFLE classification. However, hypophosphatemia was not associated with adverse clinical outcomes, including the requirement of mechanical ventilation, an increased ICU length of stay, or higher mortality, even after excluding patients with renal injury according to the RIFLE classification. Conclusion: Contrary to expectations, this study found that hypophosphatemia incidence is not higher in elderly critically ill patients than in the general ICU population. Although current literature has emphasized the association between hypophosphatemia and negative clinical outcomes, our study did not demonstrate this association, suggesting, hypophosphatemia is an indicator of disease severity rather than a risk factor for mortality.