Preoperative serum albumin level as a predictor of postoperative complication after spine fusion

STUDY DESIGN.: Retrospective cohort study. OBJECTIVE.: To investigate the association between preoperative baseline serum albumin and postoperative surgical complication. SUMMARY OF BACKGROUND DATA.: The prevalence of malnutrition in the hospitalized patient population has only been recently recognized. Preoperative hypoalbuminemia (serum albumin <3.5 g/dL) has been shown to be associated with increased morbidity and mortality rates. The prognostic implications and significance of hypoalbuminemia after spine fusion surgery remain unknown. In this study, we assess the predictive value of preoperative nutritional status (serum albumin level) on postoperative complication rates. METHODS.: The medical records of 136 consecutive patients undergoing spine fusion at Duke University Medical Center were reviewed. Preoperative serum albumin level was assessed on all patients and used to quantify nutritional status. Albumin less than 3.5 g/dL was recognized as hypoalbuminemia (malnourished). Patient demographics, comorbidities, and postoperative complication rates were collected. Patients were also stratified into 2 groups based on their cause, namely elective degenerative/deformity versus nonelective cases. The association between preoperative serum albumin level and postoperative complication was assessed via logistic regression analysis. RESULTS.: Overall, 40 (29.4%) patients experience at least 1 postoperative complication. Patients undergoing elective surgery had more complications based on preoperative albumin levels (malnourished patients: 35.7% vs. nourished patients: 11.7%, P = 0.03), whereas those undergoing nonelective surgery had similar complication rates (malnourished patients: 46.5% vs. nourished patients: 42.1%, P = 0.75). For patients undergoing elective spinal surgery, logistic regression with and without propensity score adjustment for risk factors, demonstrated that preoperative serum albumin level was a significant predictor of postoperative complications (OR: 4.21; 95% CI: 1.09-16.19; P = 0.04) and (OR: 4.54; 95% CI: 1.17-19.32; P = 0.04), respectively. CONCLUSION.: Preoperative hypoalbuminemia is an independent risk factor for postoperative complications after elective spine surgery for degenerative and deformity causes, and should be used more frequently as a prognostic tool to detect malnutrition and risk of adverse surgical outcomes.