Multidimensional Prognostic Index predicts mortality and length of stay during hospitalization in the older patients: a multicenter prospective study.

BACKGROUND: The Multidimensional Prognostic Index (MPI) is a validated predictive tool for long-term mortality based on information collected in a standardized Comprehensive Geriatric Assessment. We investigated whether the MPI is an effective predictor of intrahospital mortality and length of hospital stay after admission to acute geriatric wards.

METHODS: Prospective study of 1,178 older patients (702 women and 476 men, 85.0±6.8 years) admitted to 20 geriatrics units. Within 48 hours from admission, the MPI, according to an earlier validated algorithm, was calculated. Subjects were divided into three groups of MPI score, low-risk (MPI-1 value ≤ 0.33), moderate-risk (MPI-2 value 0.34-0.66), and severe-risk of mortality (MPI-3 value ≥ 0.67), on the basis of earlier established cut-offs. Associations with in-hospital mortality and length of stay were examined using multivariable Cox regression models and adjusted Poisson linear mixed-effects models, respectively.

RESULTS: At admission, 23.6% subjects had a MPI-1 score, 33.8% had a MPI-2 score, and 42.6% had a MPI-3 score. Subjects with higher MPI score at admission were older (p < .001), more frequently women (p < .001) and had higher prevalence of common chronic conditions. After adjustment for age, gender, and diseases, patients included in the MPI-2 and MPI-3 groups had a significantly higher risk for intrahospital mortality (hazard ratio: 3.48, 95% confidence intervals: 1.02-11.88, p = .047; hazard ratio: 8.31, 95% confidence intervals: 2.54-27.19, p < .001) than patients included in the MPI-1 group, respectively. In multivariable model, length of stay significantly increased across the three MPI groups (11.29 [0.5], 13.73 [1.3], and 15.30 [1.4] days, respectively [p < .0001]).

CONCLUSIONS: In older acute care inpatients, MPI score assessed at hospital admission is an independent predictor of in-hospital mortality and the length of hospital stay.