Geriatric Factors Improve Performance of Surgical Risk Calculator in Older Patients

By Will Boggs MD

November 09, 2019

NEW YORK (Reuters Health) - The addition of six geriatric-specific risk factors improves the predictive performance of the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) Surgical Risk Calculator (SRC) in older patients, researchers report.

"The fact that additional variables demonstrated both clinical importance as well as statistical significance was an important, interesting, and somewhat surprising finding," Dr. Clifford Y. Ko of the ACS, in Chicago, and the University of California, Los Angeles, told Reuters Health by email. "It shows that risk adjustment can often be improved, and in this case, the calculation of geriatric surgical outcomes was made better by use of such predictors."

Accurate surgical-risk assessment is a key component of patient-centered decision-making and informed consent, particularly for older adults. The SRC is widely used for this purpose.

Dr. Ko and colleagues investigated whether geriatric-specific surgical outcomes could be accurately predicted using data collected from the Geriatric Surgery Pilot Project (GSPP).

They compared the performance of the SRC in predicting four geriatric-specific postoperative outcomes (pressure ulcer, delirium, new mobility-aid use and functional decline) with and without the incorporation of six geriatric-specific preoperative risk factors (living situation, fall history, use of mobility aid, cognitive impairment, surrogate-signed consent, and palliative on admission).

Of the 21 variables in the standard SRC, CPT (Current Procedural Terminology) linear risk, chronic obstructive pulmonary disease (COPD), age, functional dependence, sex, disseminated cancer, diabetes requiring insulin and sepsis were the strongest risk predictors.

Impaired cognition, a history of falls in the past year and mobility-aid use were the strongest of the six geriatric-specific variables.

Eight of the 21 traditional risk predictors demonstrated statistical significance in the outcome prediction for at least three of the four geriatric outcomes. But only four (CPT linear risk, COPD, and age 85 years and older) were significantly predictive of increased risk for all four outcomes.

All six geriatric-specific risk factors demonstrated a significant association with at least one geriatric-specific outcome. But no single geriatric risk factor predicted all four geriatric outcomes, the researchers report in the Journal of the American College of Surgeons, online October 28. The paper was also presented at the ACS Clinical Congress 2019 in San Francisco.

Models with and without geriatric risk factors demonstrated excellent performance (as measured by C-statistic), and inclusion of geriatric risk factors improved predictive performance.

"While adding the 6 geriatric-specific predictors to the calculator does slightly increase the burden in collection, we believe that the incorporation of this tool into shared decision making will shift preoperative practice and focus clinician attention on the risk factors and outcomes that matter to the older adult patient," Dr. Ko said.

"Older adult patients are a uniquely vulnerable (and growing) surgical population who undergo more surgery and experience poorer outcomes," he said. "So we've created a tool for clinicians to help patients and their families make important decisions involving surgery."

Dr. Ko added, "In conjunction with the release of the geriatric-enhanced surgical risk calculator, ACS has launched the Geriatric Surgery Verification (GSV) Program to bring standardization and better outcomes to surgical care of the older adult patient. For more information, please visit "


J Am Coll Surg 2019.