Discriminative ability of commonly used indices to predict adverse outcomes after poster lumbar fusion: a comparison of demographics, ASA, the modified charlson comorbidity index, and the modified frailty index

• Published in: The spine journal 2018-01, Vol.18 (1), p.44-52
• Main Authors: Ondeck, Nathaniel T., B.S, Bohl, Daniel D., M.D., M.P.H, Bovonratwet, Patawut, B.S, McLynn, Ryan P., B.S, Cui, Jonathan J., B.S, Shultz, Blake N., B.A, Lukasiewicz, Adam M., M.D, Grauer, Jonathan N., M.D
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Adverse events; Aged; Aged, 80 and over; ASA; Charlson Comorbidity Index; Discriminative ability; Elective Surgical Procedures - adverse effects; Elective Surgical Procedures - methods; Female; Frail Elderly; Frailty - pathology; Frailty Index; Humans; Lumbar Vertebrae - pathology; Lumbar Vertebrae - surgery; Male; Middle Aged; Orthopedics; Posterior lumbar fusion; Postoperative Complications - epidemiology; Severity of Illness Index; Spinal Diseases - pathology; Spinal Diseases - surgery; Spinal Fusion - adverse effects; Spinal Fusion - methods
• ISSN: 1529-9430; 1878-1632
• DOI: 10.1016/j.spinee.2017.05.028

Abstract Background Context As research tools, the American Society of Anesthesiologist physical classification system (ASA), the modified Charlson Comorbidity Index (mCCI), and the modified Frailty Index (mFI) have been associated with complications following spine procedures. However, with respect to clinical utility for various adverse outcomes, no known study has compared the predictive performance of these indices specifically following posterior lumbar fusion (PLF). Purpose To compare the discriminative ability of ASA, mCCI, and mFI as well as demographic factors including age, body mass index (BMI) and gender for perioperative adverse outcomes following PLF. Study Design/Setting Retrospective review of prospectively collected data Patient Sample Patients undergoing elective PLF with or without interbody fusion were extracted from the 2011-2014 American College of Surgeons National Surgical Quality Improvement Program (NSQIP). Outcome Measures Perioperative adverse outcome variables assessed included the occurrence of minor adverse events, severe adverse events, infectious adverse events, any adverse event, extended length of hospital stay, and discharge to higher-level care. Methods Patient comorbidity indices and characteristics were delineated and assessed for discriminative ability in predicting perioperative adverse outcomes using an area under the curve analysis (AUC) from the receiver operating characteristics curves. Results In total, 16,495 patients were identified who met the inclusion criteria. The most predictive comorbidity index was ASA and demographic factor was age. Of these two factors, age had the larger discriminative ability for 3 out of the 6 adverse events and ASA was the most predictive for 1 out of 6 adverse outcomes. A combination of the most predictive demographic factor and comorbidity index, resulted in improvements in discriminative ability over the individual components for 5 of the 6 outcome variables. Conclusion For posterior lumbar fusion, easily obtained patient ASA and age have overall similar or better discriminative abilities for perioperative adverse outcomes than numerically tabulated indices that have multiple inputs and are harder to implement in clinical practice.