In-hospital mortality rates, complication rates, length of stay, and total costs of >14,000 chronic subdural hematomas treated in the U.S. between 2016 and 2020: Query of the premier health-care database
- Department of Neurosurgery, Geisinger, Wilkes-Barre, Pennsylvania,
- Department of Neurosurgery, Geisinger, Danville, Pennsylvania, United States.
Itay Melamed, Department of Neurosurgery, Geisinger, Wilkes-Barre, Pennsylvania, United States.
DOI:10.25259/SNI_508_2022Copyright: © 2022 Surgical Neurology International This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
How to cite this article: Philipp Hendrix1,2, Oded Goren2, Shamsher Dalal2, Ulrick Sidney Kanmounye2, Gregory M. Weiner1, Clemens M. Schirmer1,2, Itay Melamed1. In-hospital mortality rates, complication rates, length of stay, and total costs of >14,000 chronic subdural hematomas treated in the U.S. between 2016 and 2020: Query of the premier health-care database. 19-Aug-2022;13:364
How to cite this URL: Philipp Hendrix1,2, Oded Goren2, Shamsher Dalal2, Ulrick Sidney Kanmounye2, Gregory M. Weiner1, Clemens M. Schirmer1,2, Itay Melamed1. In-hospital mortality rates, complication rates, length of stay, and total costs of >14,000 chronic subdural hematomas treated in the U.S. between 2016 and 2020: Query of the premier health-care database. 19-Aug-2022;13:364. Available from: https://surgicalneurologyint.com/?post_type=surgicalint_articles&p=11814
Background: With the drastically aging population in the U.S., chronic subdural hematomas (cSDHs) are projected to represent the most common neurosurgical diagnosis requiring treatment within the next two decades. There is lack of contemporary outcome data in patients treated for nontraumatic and nonacute subdural hematoma. We aim to portray current mortality rates, complication rates, length of stay, and costs associated with inpatient cSDH care.
Methods: The Premier Health-care Database, Premier Inc., Charlotte/NC was queried for encounters October 2016–December 2020 with the ICD-10 diagnoses of nontraumatic nonacute subdural hematoma as the principal diagnosis among patients age ≥40 years. Per database in-hospital mortality is defined as mortality in an inpatient who is not discharged. Complications represent medical conditions not present on admission that affects mortality, length of stay, and costs within the database.
Results: The query identified 14,136 inpatient encounters. Between October 2016 and December 2020, in-hospital mortality rates averaged 10.9% in the medical group (MG) and 3.6% in the surgical group (SG) (P P P
Conclusion: The standardized outcomes presented represent an objective benchmark of contemporary cSDH treatment outcomes in the U.S. With the projected substantial increase of cSDH cases within the next decades, new treatment strategies such as middle meningeal embolization need to be explored and outperform current outcome metrics.
Keywords: Complications, Health-care database, Mortality, Subdural hematoma
Chronic subdural hematoma (cSDH) represents a prototypical disease of the elderly. Due to the demographic changes driven by an aging population with increased life expectancies, cSDH incidence has been increasing worldwide. Projections quantified cSDH to become the most prevalent neurosurgical diagnosis requiring treatment by 2030, hence, putting a substantial burden on the health-care systems.[
Optimizing outcomes by reducing hematoma recurrence, length of inpatient stays, and complications as well as improving functional outcomes are fundamental to mitigate the clinical, economic, and health-care burden of cSDHs. Contemporary outcome data for inpatient cSDH patients are lacking. The present study aimed to provide a comprehensive understanding of in-hospital mortality, complication rates, length of stay, and costs that portray the contemporary burden of cSDH in the U.S.
The authors queried the Premier Health-care Database (PHD, Premier Inc., Charlotte, NC) to provide outcomes of more than 14,000 U.S. inpatient cases with nontraumatic and nonacute subdural hematomas treated between 2016 and 2020.
The PHD, Premier Inc, Charlotte, NC is an all-payer database that collects U.S. hospital-based information. To date, the database exceeds 1 billion patient encounters from over 230 million unique patients and 120 million inpatient admissions. Supplied by more than 800 U.S. hospitals, about 20% of all U.S. inpatient discharges over the past decade are congregated in the PHD. For this analysis, the authors queried the database for all patients between October 2016 and December 2020 using the parameters of ICD-10 I62.00, I62.02, and I62.03 as the principal diagnosis. For all eligible patients, outcome data elements for in-hospital mortality, complications, length of stay, and costs were collected. Data were grouped into surgically and medically treated patients and further stratified by age, sex, race, and year of treatment.
Per PHD, in-hospital mortality is defined as a mortality in an inpatient who is not discharged to another facility, hospital, or center. Complications are defined as medical conditions not present on admission that affect mortality, length of stay, and costs. Eighteen predefined hospital acquired conditions – such as infections, falls, venous thromboembolism, and serious preventable events – plus another 82 conditions identified by Premier comprise these clinical conditions. Length of stay represents time spent as inpatient. Costs are obtained from either data submitted by the hospital’s or health-care system’s accounting system or are calculated based on annual Medicare cost reports. Medical and surgical treatment groups were compared using Student’s t-tests within the PHD.
In the study period October 2016–December 2020, a total of 14,136 inpatient cases were available for analysis with 6821 in the medical group (MG) and 7315 in the surgical group (SG). In the MG, 59.1% were male, 72.7% were Caucasian, 46.2% were between 60 and 79 years old, and 36.7% were ≥80 years old. In the SG, 71.5% were male, 69.7% were Caucasian, 57.5% were between 60 and 70 years old, and 25.5% were ≥80 years old [
Collectively, in-hospital mortality rate was 10.88% in the MG and 3.61% in the SG (P < 0.001). Descriptively, in the MG, it was highest in females, patients ≥80 years and Afro-American race, while its annual average trended toward a decline during the study period 2016–2020. In the SG, the in-hospital mortality was similar in males and females. It was higher in patients ≥80 years and highest among the American Indian race which, however, represented only a small fraction of all cases (52/7315, 0.71% of surgical cases). The in-hospital mortality rates remained stable during the study period [
The complication rate in the MG was 8.86% and 19.86% in the SG (P < 0.001). In the MG, it was higher in females, patients ≥80 years, and nonCaucasians. The annual average during the study period was stable with a marked increase from about 8–10% in 2020. In the SG, the averaged complication rate was 19.86% and similar in males and females. It was higher in patients ≥80 years and highest among the American Indian race which, however, represented only a small fraction of all cases. The average complication rate declined annually during the study period [
Length of stay
Average length of stay in the MG was 3.01 days and significantly shorter than average length of stay in the SG with 5.74 (P < 0.001). Overall, among subgroups of sex, age, race, and year, lengths of stay were similar within the surgical and medical subgroups.
Total cost average was $10,234 in the MG and $26,659 in the SG (P < 0.001). While among subgroups of sex, age, and year costs were similar, there was considerable disparity of costs in both the medical and SGs among races.
While there are numerous studies exploring outcomes in acute and traumatic subdural hematomas, contemporary data of U.S. inpatient treatment for nonacute and nontraumatic subdural hematomas are lacking. The aim of this study was therefore to provide contemporary objective outcome descriptive of surgically and medically treated inpatients ≥40 years suffering from cSDH. These data points provide an objective benchmark for yet to come prospective trials that aim to elucidate the efficacy of MMA embolization.
Medical complications and comorbidities are the predominant driver of in-hospital mortality among cSDH patients. Intracranial hemorrhage and infection such as subdural empyema represent severe but rare complications generating poor outcomes among surgically treated cSDH patients.[
There herein presented PHD query provided contemporary descriptive outcomes of nontraumatic nonacute SDH ≥40 years which may represent typical candidates for MMA embolization trials. In the unmatched comparison, medically treated cSDH had significantly higher mortality compared to surgically treated patients. In contrast, the complication rate, length of stay, and costs were significantly higher in the SG.
Allocation of patients into the medical or SGs is likely to be highly biased by criteria such as hematoma thickness, midline shift, neurological status, and comorbidities. Administrative database such as the NIS or PHD is subject to recruitment bias since only a subset of nationwide health systems are affiliated with databases. Despite these shortcomings, database queries such as the one presented here delineate objective aggregated data that portrays baseline data supporting generation of future study designs and facilitating appropriate power calculations. The lack of access to further individual patient level data did not allow further dataset analysis.
The standardized outcomes presented represent an objective benchmark of contemporary cSDH treatment outcomes in the U.S. With the projected substantial increase of cSDH cases within the next decades, new treatment strategies need to be explored and outperform current outcome metrics.
Patients’ consent not required as patients’ identities were not disclosed or compromised.
There are no conflicts of interest.
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