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Kimon Bekelis, Symeon Missios, Shannon Coy and Jeremiah N. Johnson

OBJECTIVE

The accuracy of public reporting in health care, especially from private vendors, remains an issue of debate. The authors investigated the association of the publicly reported physician complication rates in an online platform with real-world adverse outcomes of the same physicians for patients undergoing posterior lumbar fusion.

METHODS

The authors performed a cohort study involving physicians performing posterior lumbar fusions between 2009 and 2013 who were registered in the Statewide Planning and Research Cooperative System database. This cohort was merged with publicly available data over the same time period from ProPublica, a private company. Mixed-effects multivariable regression models were used to investigate the association of publicly available complication rates with the rate of discharge to a rehabilitation facility, length of stay, mortality, and hospitalization charges for the same surgeons.

RESULTS

During the selected study period, there were 8,457 patients in New York State who underwent posterior lumbar fusion performed by the 56 surgeons represented in the ProPublica Surgeon Scorecard over the same time period. Using a mixed-effects multivariable regression model, the authors demonstrated that publicly reported physician-level complication rates were not associated with the rate of discharge to a rehabilitation facility (OR 0.97, 95% CI 0.72–1.31), length of stay (adjusted difference −0.1, 95% CI −0.5 to 0.2), mortality (OR 0.87, 95% CI 0.49–1.55), and hospitalization charges (adjusted difference $18,735, 95% CI −$59,177 to $96,647). Similarly, no association was observed when utilizing propensity score–adjusted models, and when restricting the cohort to a predefined subgroup of Medicare patients.

CONCLUSIONS

After merging a comprehensive all-payer posterior lumbar fusion cohort in New York State with data from the ProPublica Surgeon Scorecard over the same time period, the authors observed no association of publicly available physician complication rates with objective outcomes.

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Kimon Bekelis, Dan Gottlieb, Nicos Labropoulos, Yin Su, Stavropoula Tjoumakaris, Pascal Jabbour and Todd A. MacKenzie

OBJECTIVE

The impact of combined practices on the outcomes of unruptured cerebral aneurysm coiling remains an issue of debate. The authors investigated the association of combined open and endovascular expertise with the outcomes of unruptured cerebral aneurysm coiling.

METHODS

The authors performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who underwent endovascular coiling for unruptured cerebral aneurysms between 2007 and 2012. To control for confounding, the authors used propensity score conditioning, with mixed effects to account for clustering at the hospital referral region level.

RESULTS

During the study period, there were 11,716 patients who underwent endovascular coiling for unruptured cerebral aneurysms and met the inclusion criteria. Of these, 1186 (10.1%) underwent treatment performed by hybrid neurosurgeons, and 10,530 (89.9%) by proceduralists who performed only endovascular coiling. Multivariable regression analysis with propensity score adjustment demonstrated a lack of association of combined practice with 1-year postoperative mortality (OR 0.84; 95% CI 0.58–1.23), discharge to rehabilitation (OR 1.0; 95% CI 0.66–1.51), 30-day readmission rate (OR 1.07; 95% CI 0.83–1.38), and length of stay (adjusted difference, 0.41; 95% CI −0.26 to 1.09). Higher procedural volume was independently associated with improved outcomes.

CONCLUSIONS

In a cohort of Medicare patients, the authors did not demonstrate a difference in mortality, discharge to rehabilitation, readmission rate, and LOS between hybrid neurosurgeons and proceduralists performing only endovascular coiling.

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Kimon Bekelis, Joanna S. Kerley-Hamilton, Amy Teegarden, Craig R. Tomlinson, Rachael Kuintzle, Nathan Simmons, Robert J. Singer, David W. Roberts, Manolis Kellis and David A. Hendrix

OBJECTIVE

The molecular mechanisms behind cerebral aneurysm formation and rupture remain poorly understood. In the past decade, microRNAs (miRNAs) have been shown to be key regulators in a host of biological processes. They are noncoding RNA molecules, approximately 21 nucleotides long, that posttranscriptionally inhibit mRNAs by attenuating protein translation and promoting mRNA degradation. The miRNA and mRNA interactions and expression levels in cerebral aneurysm tissue from human subjects were profiled.

METHODS

A prospective case-control study was performed on human subjects to characterize the differential expression of mRNA and miRNA in unruptured cerebral aneurysms in comparison with control tissue (healthy superficial temporal arteries [STA]). Ion Torrent was used for deep RNA sequencing. Affymetrix miRNA microarrays were used to analyze miRNA expression, whereas NanoString nCounter technology was used for validation of the identified targets.

RESULTS

Overall, 7 unruptured cerebral aneurysm and 10 STA specimens were collected. Several differentially expressed genes were identified in aneurysm tissue, with MMP-13 (fold change 7.21) and various collagen genes (COL1A1, COL5A1, COL5A2) being among the most upregulated. In addition, multiple miRNAs were significantly differentially expressed, with miR-21 (fold change 16.97) being the most upregulated, and miR-143–5p (fold change −11.14) being the most downregulated. From these, miR-21, miR-143, and miR-145 had several significantly anticorrelated target genes in the cohort that are associated with smooth muscle cell function, extracellular matrix remodeling, inflammation signaling, and lipid accumulation. All these processes are crucial to the pathophysiology of cerebral aneurysms.

CONCLUSIONS

This analysis identified differentially expressed genes and miRNAs in unruptured human cerebral aneurysms, suggesting the possibility of a role for miRNAs in aneurysm formation. Further investigation for their importance as therapeutic targets is needed.

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Kimon Bekelis, Symeon Missios and Robert J. Spinner

OBJECT

Despite the growing epidemic of falls, the true incidence of peripheral nerve injuries (PNIs) in this patient population remains largely unknown.

METHODS

The authors performed a retrospective cohort study of 839,210 fall-injured patients who were registered in the National Trauma Data Bank (NTDB) between 2009 and 2011 and fulfilled the inclusion criteria. Regression techniques were used to investigate the association of demographic and socioeconomic factors with the rate of PNIs in this patient population. The association of age with the incidence of PNIs was also investigated.

RESULTS

Overall, 3151 fall-injured patients (mean age 39.1 years, 33.3% females) sustained a PNI (0.4% of all falls). The respective incidence of PNIs was 2.7 per 1000 patients for ground-level falls, 4.9 per 1000 patients for multilevel falls, and 4.5 per 1000 patients for falls involving force. This demonstrated a rapid increase in the first 2 decades of life, with a maximum rate of 1.1% of all falls in the 3rd decade, followed by a slower decline and eventual plateau in the 7th decade. In a multivariable analysis, the association of PNIs with age followed a similar pattern with patients 20–29 years of age, demonstrating the highest association (OR 2.34 [95% CI 2.0–2.74] in comparison with the first decade of life). Falls involving force (OR 1.25 [95% CI 1.14–1.37] in comparison with multilevel falls) were associated with a higher incidence of PNIs. On the contrary, female sex (OR 0.87 [95% CI 0.80–0.84]) and ground-level falls (OR 0.79 [95% CI 0.72–0.86]) were associated with a lower rate of PNIs.

CONCLUSIONS

Utilizing a comprehensive national database, the authors demonstrated that PNIs are more common than previously described in fall-injured patients and identified their age distribution. These injuries are associated with young adults and falls of high kinetic energy.

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Kimon Bekelis, Symeon Missios, Todd A. MacKenzie, Atman Desai, Adina Fischer, Nicos Labropoulos and David W. Roberts

Object

Precise delineation of individualized risks of morbidity and mortality is crucial in decision making in cerebrovascular neurosurgery. The authors attempted to create a predictive model of complications in patients undergoing cerebral aneurysm clipping (CAC).

Methods

The authors performed a retrospective cohort study of patients who had undergone CAC in the period from 2005 to 2009 and were registered in the Nationwide Inpatient Sample (NIS) database. A model for outcome prediction based on preoperative individual patient characteristics was developed.

Results

Of the 7651 patients in the NIS who underwent CAC, 3682 (48.1%) had presented with unruptured aneurysms and 3969 (51.9%) with subarachnoid hemorrhage. The respective inpatient postoperative risks for death, unfavorable discharge, stroke, treated hydrocephalus, cardiac complications, deep vein thrombosis, pulmonary embolism, and acute renal failure were 0.7%, 15.3%, 5.3%, 1.5%, 1.3%, 0.6%, 2.0%, and 0.1% for those with unruptured aneurysms and 11.5%, 52.8%, 5.5%, 39.2%, 1.7%, 2.8%, 2.7%, and 0.8% for those with ruptured aneurysms. Multivariate analysis identified risk factors independently associated with the above outcomes. A validated model for outcome prediction based on individual patient characteristics was developed. The accuracy of the model was estimated using the area under the receiver operating characteristic curve, and it was found to have good discrimination.

Conclusions

The featured model can provide individualized estimates of the risks of postoperative complications based on preoperative conditions and can potentially be used as an adjunct in decision making in cerebrovascular neurosurgery.

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Symeon Missios, Kimon Bekelis and David W. Roberts

Paul of Aegina (625–690 AD) was born on the island of Aegina and was one of the most prominent physician-writers of the Byzantine Empire. His work Epitome of Medicine, comprised of 7 books, was a comprehensive compendium of the medical and surgical knowledge of his time and was subsequently translated into multiple languages. Paul of Aegina made valuable contributions to neurosurgical subjects and described procedures for the treatment of nerve injuries, hydrocephalus, and fractures of the skull and spine. His work combined the ancient knowledge of Hippocrates and Galen with contemporary medical observations and served as a bridge between Byzantine and Arabic medicine. He is considered to be one of the great ancient Greek medical writers and his work has influenced the subsequent evolution of Western European and Arab medicine. This paper provides an account of his contribution to the management of neurosurgical pathologies during the Byzantine era, as described in his medical compendium, Epitome of Medicine.

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Atman Desai, Kimon Bekelis, Wenyan Zhao, Perry A. Ball and Kadir Erkmen

Object

Stroke is a leading cause of death and disability. Given that neurologists and neurosurgeons have special expertise in this area, the authors hypothesized that the density of neuroscience providers is associated with reduced mortality rates from stroke across US counties.

Methods

This is a retrospective review of the Area Resource File 2009–2010, a national county-level health information database maintained by the US Department of Health and Human Services. The primary outcome variable was the 3-year (2004–2006) average in cerebrovascular disease deaths per million population for each county. The primary independent variable was the combined density of neurosurgeons and neurologists per million population in the year 2006. Multiple regression analysis was performed, adjusting for density of general practitioners (GPs), urbanicity of the county, and socioeconomic status of the residents of the county.

Results

In the 3141 counties analyzed, the median number of annual stroke deaths was 586 (interquartile range [IQR] 449–754), the median number of neuroscience providers was 0 (IQR 0–26), and the median number of GPs was 274 (IQR 175–410) per million population. On multivariate adjusted analysis, each increase of 1 neuroscience provider was associated with 0.38 fewer deaths from stroke per year (p < 0.001) per million population. Rural location (p < 0.001) and increased density of GPs (p < 0.001) were associated with increases in stroke-related mortality.

Conclusions

Higher density of specialist neuroscience providers is associated with fewer deaths from stroke. This suggests that the availability of specialists is an important factor in survival after stroke, and underlines the importance of promoting specialist education and practice throughout the country.