Prognostic value of the geriatric nutritional risk index and other hematological markers on long‐term survival in the geriatric population

Objectives The prognostic value of hematological markers has not been extensively explored in the geriatric population, particularly in the presence of the frailty phenotype among hospitalized individuals. Therefore, our study aimed to assess the influence of the frailty phenotype in hospitalized geriatric individuals on hematological markers and their impact on short‐ and long‐term outcomes. Methods This is a secondary analysis of a prospective cohort study. This study involved hospitalized individuals who were followed during their hospitalization and for nearly 2 years after discharge. At baseline, Fried's frailty phenotype was assessed, as well as hematological markers, including neutrophil–lymphocyte ratio, monocyte–lymphocyte ratio, neutrophil–monocyte ratio, platelet–lymphocyte ratio, systemic inflammation index, prognostic nutritional index, geriatric nutritional risk index (GNRI), and C‐reactive protein–albumin ratio. The phase angle derived from bioelectrical impedance analysis was likewise considered a prognostic biomarker. Our main outcomes were hospital length of stay and mortality during follow‐up. Results Frailty occurred in 43.2% of the population. Individuals with the frailty phenotype exhibited worse hematological markers and lower phase angle values. Low GNRI and elevated C‐reactive protein–albumin ratio values were independently associated with mortality (hazard ratio = 6.88, 95% confidence interval 2.0–23.6; hazard ratio = 2.2, 95% confidence interval 1.1–4.4). Only higher values of the systemic inflammation index were independently associated with prolonged hospital stays. Conclusion Hematological markers may serve as a feasible tool for prognostic assessment. Individuals with the frailty phenotype and low GNRI represented a worst‐case scenario. Geriatr Gerontol Int 2024; 24: 312–318. Our research investigated the influence of hematological and other biomarkers on both short‐ and long‐term clinical outcomes among hospitalized patients, categorized based on the frailty phenotype. We found that a low geriatric nutritional risk index and a high C‐reactive protein–albumin ratio were independently associated with increased long‐term mortality.