The Association Between Comorbidities and Medical Complications for Adult Spinal Deformity Surgery: What Factors Have the Greatest Impact on Adverse Events and Outcomes?

Study designNarrative review.ObjectiveIt is known that adult spinal deformity surgery (ASD) is associated with a high medical complication rate. However, it remains unclear which comorbidities impact these adverse events. The purpose of this study was to review the current knowledge regarding the association between postoperative medical complications and comorbidities.MethodsThe literatures in English were searched using PubMed. The search method involved a combination of keywords including "adult spinal deformity," "complication," and each specific risk factor. The search was limited to items listed in PubMed by February 15, 2022. The odds ratio (OR) of medical complications and mortality were evaluated.ResultsA total of 94 publications were reviewed. The risk factors with the higher OR for medical complications were frailty (OR: 4.4, 95% CI: 2.0-9.9), ASA class 4 (OR: 3.58, 95% CI: 2.00-6.39), male sex (OR: 3.52, 95% CI: 1.78-6.96), malnutrition (OR: 2.89, 95% CI: 1.69-4.93), and pathologic weight loss (OR: 2.38, 95% CI: 2.01-2.81). Similarly, the risk factors with the higher OR for mortality were liver disease (OR: 36.09, 95% CI: 16.16-80.59), pathologic weight loss (OR: 7.28, 95% CI: 4.36-12.14), renal failure (OR: 5.51, 95% CI: 2.57-11.82), chronic heart failure (OR: 5.67, 95% CI: 3.3-9.73), and age over 65 (OR: 3.49, 95% CI: 2.31-5.29).ConclusionThis review demonstrates the impact of a patient's comorbidities on postoperative medical complications. Understanding the level of risk involved can help to provide surgeons and patients with the information required to determine the suitability for surgery.