Current risk prediction methods ignore functional status which is critical in assessing suitability of older veterans to undergo major surgery. Our prior work with older veterans undergoing surgery indicated that low preoperative function derived from the Veteran Rand (VR-12) survey in the form of a summary physical component score (PCS) independently predicted a trend towards more venous thromboembolism. We believe that this measure along with the mental component score (MCS), also from VR-12, could more globally predict an adverse postoperative course in the form of any one of a number of medical complications, discharge to nursing home, readmission within 30 days, and death.
To measure the association of preoperative PCS and MCS on the 30 day risk of any serious medical complication, discharge to nursing home, readmission within 30 days, and death. And secondarily to measure the incremental improvement in predictive power for the newly published American College of Surgeons Universal Risk Calculator enhanced with MCS and PCS compared to the ACS calculator alone.
We identified male veterans age 65 and older who underwent major surgery and completed the VR-12 survey - distributed as part of VA consumer satisfaction survey - Survey of Health Experiences of Patients (SHEP) - in the six months prior to surgery. We analyzed PCS and MCS in deciles and then quartiles to examine for trends and possible threshold values. We then measured the independent association between PCS and MCS with each of our outcomes using logistic regression. Finally we checked the change in c-statistic for the outcome serious complication for the ACS calculator enhanced with MCS and PCS compared to the ACS calculator alone.
We identified 2,503 surgeries in older male veterans who completed a VR-12 survey in the 6 months before surgery. Being in the lowest quartile PCS (versus highest quartile) predicted more than a twofold increase in the risk of serious complication (OR=2.27 95% CI 1.43-3.60), 1.9 fold increase in the risk of discharge to nursing home (OR=1.86 95% CI 1.30-2.66), and a 1.8 fold increase in the risk of readmission (OR=1.80 95% CI 1.37-2.39). The lowest quartile of MCS predicted each outcome although to a lesser extent than PCS. The enhanced model improved the c-statistic of the original model by 0.069 (95% CI 0.027-0.110).
Clinicians and policymakers should consider the incorporation of self-reported function derived from short form instruments like VR-12 when assessing older veterans for major surgery. Future interventions to improve suitability of these veterans to undergo surgery may hinge on the results of a screening process which incorporates VR-12.
- Kapoor A, Chew PW, Reisman JI, Berlowitz DR. Low Self-Reported Function Predicts Adverse Postoperative Course in Veterans Affairs Beneficiaries Undergoing Total Hip and Total Knee Replacement. Journal of the American Geriatrics Society. 2016 Apr 1; 64(4):862-9.