Outcome prediction with Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity score system in elderly patients submitted to elective surgery.

Context: Elderly patients have a higher risk of complications and 30-day mortality than younger patients. Population is aging and this is an emergent preoccupation.

Aims: The aim of this study was to evaluate the performance of Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity (POSSUM) system on 30-day mortality in elderly patients submitted to elective surgery. Additionally, the correlation of WHODAS 2.0 and Clinical Frailty Score (CFS) with mortality was evaluated.

Settings and Design: An observational prospective study was conducted between May and July 2017.

Methods and Material: Patients submitted to elective orthopedic, gynecologic, urologic, vascular, plastic, and general surgery were included. Exclusion criteria were as follows: age <60 years old; inability to give informed consent; emergency/urgency surgery, inability to understand Portuguese; patients admitted in the ICU after surgery. POSSUM was used to estimate postoperative mortality risk. WHODAS 2.0 and CFS were used to assess quality of life and health status. Mortality was evaluated during hospital stay and 30 days after surgery. area under the receiver operating characteristic (AUROC) was analyzed to test the discrimination of P-POSSUM, WHODAS 2.0 and CFS scale.

Statistical Analysis Used: Statistical analysis was done using the SPSS Software (version 24.0).

Results: POSSUM-predicted mortality was 3.0% with a standardized mortality ratio = 0.87; 95% CI 0.62-0.93; and a good calibration (H-L: P = 0.646); however, the AUROC was poor (0.563). We identified an association between mortality and a higher CFS grade ( P = 0.000 and AUROC = 0.859) and a higher WHODAS 2.0 score ( P = 0.000 and AUROC = 0.808).

Conclusions: WHODAS and CFS appear to be a better assessment tolls for predicting postoperative mortality with a good discrimination comparing with P-POSSUM system.