Scott A. Meyer and Praveen V. Mummaneni
Christopher I. Shaffrey
John R. W. Kestle
Scott L. Parker, David N. Shau, Stephen K. Mendenhall and Matthew J. McGirt
Revision lumbar fusion procedures are technically challenging and can be associated with tremendous health care resource utilization and cost. There is a paucity of data regarding specific factors that significantly contribute to increased cost of care. In light of this, the authors set out to identify independent risk factors predictive of increasing 2-year direct health care costs after revision lumbar fusion.
One hundred fifty patients undergoing revision instrument-assisted fusion for adjacent-segment disease (50 cases), pseudarthrosis (47 cases), or same-level stenosis (53 cases) were included in this study. Patient demographics, comorbidities, preoperative health states as assessed by patient-reported outcome questionnaires and perioperative complications were collected and analyzed. Two-year back-related medical resource utilization and direct health care costs were assessed. The independent association of all variables to increasing cost was assessed using multivariate linear regression analysis.
There was a wide range ($24,935–$63,769) in overall 2-year direct costs for patients undergoing revision lumbar fusion (mean $32,915 ± $8344 [± SD]). Preoperative variables independently associated with 2-year direct health care costs included diagnosis of congestive heart failure, more severe leg pain (visual analog scale), greater back-related disability (Oswestry Disability Index), and worse mental health (12-Item Short Form Health Survey Mental Component Summary score). There was a 1.1- to 1.2-fold increase in cost for patients in the greatest quartiles compared with those in the lowest quartiles for these variables. Surgical site infection, return to the operating room, and spine-related hospital readmission during the 90-day global health period were postoperative variables independently associated with 2-year cost. Patients in the greatest versus lowest quartiles had a 1.7- to 1.9-fold increase in cost for these variables.
Revision lumbar fusion can be associated with considerable 2-year health care costs. These costs can also vary widely among patients, as evidenced by the 2.6-fold overall cost range in this series. Although comorbidities and preoperative severity of disease states contribute to cost of care, the primary drivers of increased cost include perioperative complications such as surgical site infection, return to the operating room, and readmission during the global health period. Measures focused on health service improvement will be most successful in reducing the cost of care for patients undergoing revision lumbar fusion.
Kaisorn Chaichana, Scott Parker, Alessandro Olivi and Alfredo Quiñones-Hinojosa
Glioblastoma multiforme (GBM) is the most common and aggressive type of primary brain tumor in adults. Although the average survival is ~ 12 months, individual survival is heterogeneous. The ability to predict short- and long-term survivors is limited. Therefore, the aims of this study were to ascertain preoperative risk factors associated with survival, develop a preoperative prognostic grading system, and evaluate the utility of this grading system in predicting survival for patients undergoing resection of a primary intracranial GBM.
Cases involving adult patients who underwent surgery for an intracranial primary (de novo) GBM between 1997 and 2007 at The Johns Hopkins Hospital, an academic tertiary-care institution, were retrospectively reviewed. Multivariate proportional hazards regression analysis was used to identify preoperative factors associated with survival, after controlling for extent of resection and adjuvant therapies. The identified associations with survival were then used to develop a grading system based on preoperative variables. Survival as a function of time was plotted using the Kaplan-Meier method, and survival rates were compared using Log-rank analysis. Associations with p < 0.05 were considered statistically significant.
Of the 393 patients in this study, 310 (79%) had died as of most recent follow-up (median time from surgery to death 11.9 months). The preoperative factors, independent of extent of resection and adjuvant therapies (carmustine wafers, temozolomide, and radiation), found to be negatively associated with survival were: age > 60 years (p < 0.0001), Karnofsky performance status score ≤ 80 (p < 0.0001), motor deficit (p = 0.02), language deficit (p = 0.001), and periventricular tumor location (p = 0.04). Patients possessing 0–1, 2, 3, and 4–5 of these variables were assigned a preoperative grade of 1, 2, 3, and 4, respectively. Patients with a preoperative grade of 1, 2, 3, and 4 had a median survival of 16.6, 10.2, 6.8, and 6.1 months, respectively.
The present study found that older age, poor performance status, motor deficit, language deficit, and periventricular tumor location independently predicted poorer survival in patients undergoing GBM resection. A grading system based on these factors was able to identify 4 distinct groups of patients with different survival rates. This grading system, based only on preoperative variables, may provide patients and physicians with prognostic information that may guide medical and surgical therapy before any intervention is pursued.
John R. W. Kestle
Kaisorn L. Chaichana, Scott L. Parker, Alessandro Olivi and Alfredo Quiñones-Hinojosa
Seizures are a common presenting symptom and cause of morbidity for patients with malignant astrocytomas. The authors set out to determine preoperative seizure characteristics, effects of surgery on seizure control, and factors associated with prolonged seizure control in patients with malignant astrocytomas.
Cases involving adult patients who underwent primary resection of a hemispheric anaplastic astrocytoma (AA) or glioblastoma multiforme (GBM) at the Johns Hopkins Medical Institutions between 1996 and 2006 were retrospectively reviewed. Multivariate logistical regression analysis was used to identify associations with pre-operative seizures, and multivariate proportional hazards regression analyses were used to identify associations with prolonged seizure control following resection.
Of the 648 patients (505 with GBM, 143 with AA) in this series, 153 (24%) presented with seizures. The factors more commonly associated with preoperative seizures were AA pathology (p = 0.03), temporal lobe involvement (p = 0.04), and cortical location (p = 0.04), while the factors less commonly associated with preoperative seizures were greater age (p = 0.03) and larger tumor size (p ≤ 0.001). Among those patients with a history of seizures, outcome 12 months after surgery was Engel Class I (seizure free) in 77%, Class II (rare seizures) in 12%, Class III (meaningful improvement) in 6%, and Class IV (no improvement) in 5%. Postoperative seizures were rare in patients without a history of preoperative seizures. The factor positively associated with prolonged seizure control was increased Karnofsky Performance Scale score (p = 0.002), while the factors negatively associated with seizure control were preoperative uncontrolled seizures (p = 0.03) and parietal lobe involvement (p = 0.005). Seizure recurrence in patients with postoperative seizure control was independently associated with tumor recurrence (p = 0.006).
The identification and consideration of factors associated with prolonged seizure control may help guide treatment strategies aimed at improving the quality of life for patients with malignant astrocytomas.
Scott L. Parker, Anthony L. Asher, Saniya S. Godil, Clinton J. Devin and Matthew J. McGirt
The health care landscape is rapidly shifting to incentivize quality of care rather than quantity of care. Quality and outcomes registry platforms lie at the center of all emerging evidence-driven reform models and will be used to inform decision makers in health care delivery. Obtaining real-world registry outcomes data from patients 12 months after spine surgery remains a challenge. The authors set out to determine whether 3-month patient-reported outcomes accurately predict 12-month outcomes and, hence, whether 3-month measurement systems suffice to identify effective versus noneffective spine care.
All patients undergoing lumbar spine surgery for degenerative disease at a single medical institution over a 2-year period were enrolled in a prospective longitudinal registry. Patient-reported outcome instruments (numeric rating scale [NRS], Oswestry Disability Index [ODI], 12-Item Short Form Health Survey [SF-12], EQ-5D, and the Zung Self-Rating Depression Scale) were recorded prospectively at baseline and at 3 months and 12 months after surgery. Linear regression was performed to determine the independent association of 3- and 12-month outcome. Receiver operating characteristic (ROC) curve analysis was performed to determine whether improvement in general health state (EQ-5D) and disability (ODI) at 3 months accurately predicted improvement and achievement of minimum clinical important difference (MCID) at 12 months.
A total of 593 patients undergoing elective lumbar surgery were included in the study. There was a significant correlation between 3-month and 12-month EQ-5D (r = 0.71; p < 0.0001) and ODI (r = 0.70; p < 0.0001); however, the authors observed a sizable discrepancy in achievement of a clinically significant improvement (MCID) threshold at 3 versus 12 months on an individual patient level. For postoperative disability (ODI), 11.5% of patients who achieved an MCID threshold at 3 months dropped below this threshold at 12 months; 10.5% of patients who did not meet the MCID threshold at 3 months continued to improve and ultimately surpassed the MCID threshold at 12 months. For ODI, achieving MCID at 3 months accurately predicted 12-month MCID with only 62.6% specificity and 86.8% sensitivity. For postoperative health utility (EQ-5D), 8.5% of patients lost an MCID threshold improvement from 3 months to 12 months, while 4.0% gained the MCID threshold between 3 and 12 months postoperatively. For EQ-5D (quality-adjusted life years), achieving MCID at 3 months accurately predicted 12-month MCID with only 87.7% specificity and 87.2% sensitivity.
In a prospective registry, patient-reported measures of treatment effectiveness obtained at 3 months correlated with 12-month measures overall in aggregate, but did not reliably predict 12-month outcome at the patient level. Many patients who do not benefit from surgery by 3 months do so by 12 months, and, conversely, many patients reporting meaningful improvement by 3 months report loss of benefit at 12 months. Prospective longitudinal spine outcomes registries need to span at least 12 months to identify effective versus noneffective patient care.