Mortality, Geriatric, and Nongeriatric Surgical Risk Factors Among the Eldest Old: A Prospective Observational Study

BACKGROUND: Preoperative risk and postoperative outcomes among the elderly are the subject of extensive debate. However, the eldest old, that is, the fastest-growing and most vulnerable group, are insufficiently studied; even their mortality rate is unclear. This prospective observational study was performed with the aim of determining the mortality rate of this population and establishing which preoperative conditions were predictors of which postoperative outcomes. The study was undertaken between 2011 and 2015 in a major tertiary care university hospital. METHODS: All patients aged >= 85 years undergoing any elective procedure during the study period were included. Patients were followed up for 30 days postoperatively. The preoperative conditions studied were demographic data, grade of surgical complexity (1-3), preoperative comorbidities, and some characteristically geriatric conditions (functional reserve, nutrition, cognitive status, polypharmacy, dependency, and frailty). The outcome measures were 30-day all-cause mortality (primary end point), morbidity, prolonged length of stay, and escalation of care in living conditions. RESULTS: Of 139 eligible patients, 127 completed follow-up. The 30-day mortality was 7.9%; 95% confidence interval (CI), 3.2-12.6. It had 3 predictors: malnutrition (odds ratio [OR], 15; 95% CI, 3-89), complexity 3 (OR, 9.1; CI, 2-52), and osteoporosis/osteoporotic fractures (OR, 14.7; CI, 2-126). Significant predictors for morbidity (40%) were ischemic heart disease (OR, 3.9; CI, 1-11) and complexity 3 (OR, 3.6; CI, 2-9), while a nonfrail phenotype (OR, 0.3; CI, 0.1-0.8) was found to be protective. Only 2 factors were found to be predictive of longer admissions, namely complexity 3 (OR, 4.4; CI, 2-10) and frailty (OR, 2.7; CI, 2-7). Finally, risk factors for escalation of care in living conditions were slow gait (a surrogate for frailty, OR, 2.5; CI, 1-6), complexity 3 (OR, 3.2; CI, 1-7), and hypertension (OR, 2.9; CI, 1-9). CONCLUSIONS: The eldest old is a distinct group with a considerable mortality rate and their own particular risk factors. Surgical complexity and certain geriatric variables (malnutrition and frailty), which are overlooked in American Society of Anesthesiologists and most other usual scores, are particularly relevant in this population. Inclusion of these factors along with appropriate comorbidities for risk stratification should guide better decision making for families and doctors alike and encourage preoperative optimization of patients.