Frailty and Severity as Determinants of Hospital Cost in the ICU

Frailty and Severity as Determinants of Hospital Cost in the Intensive Care Unit: A Retrospective Cohort Study With Partial Economic Evaluation.

This study evaluated the association between baseline frailty (mFI-11) and acute illness severity (SAPS 3) with real hospital costs in adult patients admitted to the Intensive Care Unit (ICU). The objective was to determine if frailty and severity are independent predictors of resource consumption.

A retrospective cohort study was conducted at Hospital H+ Querétaro involving 142 adult patients admitted to the ICU between January 2024 and May 2025. Baseline frailty was calculated using the 11-item Modified Frailty Index (mFI-11), and acute severity was assessed with the SAPS 3 score. Total hospital costs were obtained from institutional financial records. Multivariate models were used to adjust for comorbidities (Charlson Index) and other clinical variables to identify independent determinants of hospital expenditure.

Inclusion Criteria:

• Patients aged 18 years or older.
• Admission to the ICU between January 1, 2024, and May 31, 2025.
• Complete medical records allowing for the calculation of mFI-11, SAPS 3, and Charlson Index.
• Availability of institutional records regarding actual hospital costs.Exclusion Criteria:
• Incomplete records for primary exposure or outcome variables.
• Patients transferred from other institutions without sufficient baseline data.
• Severe inconsistencies in cost records.
• Subsequent readmissions where costs cannot be independently attributed to the index episode.