P64. Impact of body mass index on opioid consumption in lumbar spine fusion surgery

Abstract

<h3>BACKGROUND CONTEXT</h3> The prevalence of obesity continues to rise in the United States. The CDC published that from 1999-2000 through 2017-2018 the prevalence of obesity increased from 30.5% to 42.4% and the prevalence of severe obesity nearly doubled. In lumbar spine surgery, obesity is associated with increased complications, worse perioperative outcomes, and higher costs. Obesity is also linked to depression and anxiety, which have both been shown to increase the use of opioids. We hypothesize that patients who are obese require more opioids postoperatively. <h3>PURPOSE</h3> To examine the association between body mass index (BMI) and opioid consumption in patients undergoing lumbar spine fusion surgery. <h3>STUDY DESIGN/SETTING</h3> Retrospective review. <h3>PATIENT SAMPLE</h3> Three hundred and six patients who underwent one- or two-level posterior lumbar interbody fusion surgery. <h3>OUTCOME MEASURES</h3> Primary outcome measure was opioid consumption across obesity classes both while in-patient and after discharge as determined by total morphine equivalent dose (MED). Secondary outcomes included operative time, length of stay, and discharge destination. <h3>METHODS</h3> This is a retrospective review of patients who underwent one- or two-level posterior lumbar interbody fusion surgery between 2016 and 2020. Patients were stratified by BMI as follows: normal weight (18.5-24.9 kg/m2), overweight (25.0–29.9 kg/m2), obese I (30.0–34.9 kg/m2), and obese II–III (≥ 35.0 kg/m2). Patient demographics and preoperative characteristics were compared across the BMI cohorts using one-way ANOVA and chi-square analysis. <h3>RESULTS</h3> Three hundred and six patients were included in the analysis, of whom 19.3% (N=59) were normal weight, 38.9% (N=119) were overweight, 24.5% (N=75) were obese I, and 17.3% (N=53) were obese II-III. Obesity is associated with significantly longer operative times and length of stay (p<0.001, p = 0.19). There is no difference in in-house opioid consumption across groups (p = 0.207). Severely obese patients (Class II-III) are prescribed more than double the number of postoperative opioids (p = 0.001). <h3>CONCLUSIONS</h3> This study illustrates that obesity is associated with longer operative times, longer length of stay, and increased use of postoperative opioids. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.