Wednesday, September 26, 2018 9:00 AM – 10:00 AM Best Papers: 7. Predictors of total hospital resource cost during 1- or 2-level lumbar spinal fusion among Medicare beneficiaries

Abstract

PURPOSE The purpose of this study is to identify demographic factors, comorbid conditions, and procedure approaches associated with higher total hospital resources consumed by Medicare beneficiaries (MBs) during a primary 1- or 2-level lumbar spinal fusion (1-2 LLF). METHODS This retrospective study examined the calendar year 2014 Medicare inpatient standard analytical files (IPSAF) linked data for hospital claims. There were 43,117 hospitalizations where a Medicare beneficiary survived for at least 90 days following a 1-2 LLF hospitalization during the first three quarters of 2014. Multi-variable regression cost equations were estimated controlling for 8 demographic characteristics, the presence of 31 comorbid conditions, and the fusion approach or a combination of fusion approaches used during the 1-2 LLF procedures. Control variables were considered a statistically significant predictor of hospital resource use if the associated p-value was less than .01. RESULTS Overall, the majority of MBs undergoing a 1-2 LLF were white (89.5%), female (59.1%) and between 65 and 74 years of age (53.2%). Average total cost of hospital resources consumed during the initial hospitalization was $27,182±$15,569. The regression results estimated that the y-intercept for total hospital resource cost to be $21,881. The resource cost equation indicates that, compared to MBs age 80 and older, hospital costs were significantly higher (between $1,529 and $2,238) in each of the other four age groups. In addition, MBs who were non-white had significant higher estimated index hospital cost. Furthermore, 14 comorbid conditions were associated with higher incremental hospital cost and four comorbid conditions had estimated incremental cost exceeding $10,000 [malnutrition ($19,243), malignant tumor ($14,780), bone infection ($13,025), and benign tumor ($11,875)]. On the other hand, six comorbid conditions were estimated to be associated with lower hospital resource utilization. The lowest hospital resource utilization was associated with a posterior column/posterior approach technique. All other fusion approaches and combinations thereof significantly increased the estimated incremental hospital resource utilization with the anterior/posterior/anterior column/posterior approach being the most costly with an incremental increase of $26,515. CONCLUSIONS There is increasing interest in understanding the resources utilized during the hospitalization for high volume Medicare procedures such and 1-2 LLF. This study identifies 22 demographic, comorbid conditions, and fusion approaches estimated to increase incremental hospital cost by over 5% during the MBs index hospitalization. As the Medicare program continues to place hospitals at risk for the care MBs receive post discharge, it will become increasingly important to determine if care paths can be developed for MBs with selected comorbid conditions that reduce the incremental resources they are currently consuming during the initial procedure. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.