- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA
Min S. Park
Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, Utah, USA
DOI:10.4103/sni.sni_28_17Copyright: © 2017 Surgical Neurology International This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, 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: Jian Guan, Michael Karsy, William T. Couldwell, Richard H. Schmidt, Philipp Taussky, Min S. Park. Association of travel distance and cerebral aneurysm treatment. 06-Sep-2017;8:210
How to cite this URL: Jian Guan, Michael Karsy, William T. Couldwell, Richard H. Schmidt, Philipp Taussky, Min S. Park. Association of travel distance and cerebral aneurysm treatment. 06-Sep-2017;8:210. Available from: http://surgicalneurologyint.com/surgicalint-articles/association-of-travel-distance-and-cerebral-aneurysm-treatment/
Background:The management of cerebral aneurysms requires a significant level of expertise, and large areas of the country have limited access to such advanced neurosurgical care. The objective of this study was to examine the impact of longer travel distance on aneurysm management.
Methods:Adult patients treated for cerebral aneurysms from January 1, 2013 to January 1, 2016, were retrospectively identified. Demographic data, socioeconomic data, aneurysm characteristics, and postoperative outcomes were evaluated with univariate and multivariable analysis to determine factors that influenced treatment prior to or after rupture.
Results:Two hundred fifty aneurysms (87 ruptured) were treated during the study period. Patients treated after rupture were more likely than those treated before rupture to live in areas with lower median household income (62% vs. 45%, P = 0.009), to live further from the treatment center (68% vs. 40%, P P P = 0.002), lower income (1.899, 95% CI 1.003–3.596, P = 0.049), and aneurysm location (P = 0.035) remained significantly associated with treatment after rupture.
Conclusions:Patients who must travel further to receive advanced neurovascular care are more likely to receive treatment for their aneurysms only after they rupture. Further inquiry is needed to determine how to better provide neurosurgical treatment to patients living in underserved areas.
Keywords: Aneurysm clipping, cerebral aneurysm, endovascular treatment, flow diversion, travel distance
Cerebral aneurysms are estimated to be present in more than 3% of the population,[
The shortage of healthcare professionals is not limited to neurosurgery, and significant discussion is ongoing in both the medical literature[
After obtaining approval from the institutional review board with a waiver of informed consent, we queried a clinical database to obtain information about patients 18 years and older who underwent treatment for cerebral aneurysm between January 1, 2013, and January 1, 2016. Patients were excluded if geographic, demographic, or socioeconomic data were unavailable. All endovascular procedures were performed by one of two endovascular neurosurgeons, and all open surgical procedures were performed by one of four neurosurgeons. All procedures were performed at a quaternary referral center that provides care to the American Intermountain West—a geographic region comprising the states of Utah, Nevada, and parts of Idaho, Arizona, Colorado, Montana, and New Mexico and serving a population of more than 3 million.[
Demographic, geographic, socioeconomic, aneurysm- related, and postoperative information was collected on all patients. Demographic data included age, race/ethnicity (dichotomized into Caucasian and non-Caucasian), sex, marital status, and insurance type (divided into private, Medicaid/self-pay, and Medicare). Each patient's ZIP code was collected. The U.S. Census data (
Aneurysm-related data included rupture status at time of treatment, treatment modality, aneurysm size (dichotomized based on a cutoff size of 7 mm), and aneurysm location. Treatment modality was dichotomized into open clipping or endovascular (consisting of coiling with or without stent assistance and flow diversion). Aneurysm location was divided into seven categories based on those used in previous papers.[
Mapping of aneurysm distribution was performed using ArcGIS (ESRI 2011. ArcGIS Online: Release 10.3. Redlands, CA: Environmental Systems Research Institute,
Continuous variables were analyzed using Student's t-test, and categorical variables were analyzed using Chi-squared analysis. Univariate and multivariable analysis were first performed to compare patients with ruptured aneurysms and those with unruptured aneurysms (i.e., to assess timing of treatment). Variables were selected for this multivariable model based on factors that reached a P < 0.2 on univariate analysis. Univariate analysis was then used to compare patients who lived less than or greater than the median hospital travel distance. In all analyses, P < 0.05 was considered statistically significant. All statistical analyses were performed using SPSS V20.0 (IBM Corporation, Armonk, NY).
Demographic characteristics of patients in the ruptured and unruptured treatment groups were largely similar, with no significant differences between the groups in age, sex, marital status, race/ethnicity, CCI, or insurance type [
Aneurysm location differed significantly between the ruptured and unruptured groups (P < 0.001). Ruptured aneurysms were significantly more likely to arise from the anterior communicating artery, anterior cerebral artery, or posterior communicating artery, whereas those treated prior to rupture were more likely to arise from the internal carotid artery. Ruptured aneurysms were also significantly more likely to be treated with open clipping than were unruptured aneurysms (61% vs. 39%, P < 0.001).
Patients treated for ruptured aneurysms had significantly longer hospital stays than those treated for unruptured aneurysms (18.5 ± 7.9 days vs. 4.0 ± 5.6 days, P < 0.001) and were significantly less likely to discharge home (P < 0.001). Variables selected for the multivariable model included tobacco use, aneurysm size, aneurysm location, median household income, travel distance, and local FPP concentration. Discharge destination, treatment modality, and length of stay met criteria, but were not included in our model as we thought that it was unlikely these variables had an impact on aneurysm treatment timing. In our multivariable model, aneurysm location (P < 0.035,
Patients who were “far” from our medical center were similar in all assessed demographic factors when compared with the “close” group, including age, sex, race/ethnicity, and marital status [
Aneurysmal subarachnoid hemorrhage is a devastating pathology that can result in permanent disability even in survivors.[
The need to travel long distances to obtain medical care is a common problem in the United States.[
Our study suggests that patients who must travel significant distances to receive neurosurgical care for cerebral aneurysms are more than three times as likely to be treated for a ruptured aneurysm as those who live in closer proximity to a comprehensive neurovascular center. This difference is independent of other factors including socioeconomic status, aneurysm characteristics, and other demographic variables. Patients in our cohort who lived further from our center actually tended to have more ready access to primary care physicians, as indicated by a lower average FPP-to-patient ratio (1 FPP to 2572 patients in the longer distance group vs. 1 FPP to 3433 patients in the shorter distance group), possibly because of a higher population density in urban areas. With regard to timing of cerebral aneurysm treatment; however, there was no significant benefit to living in a region with a higher concentration of primary care physicians. Prior studies have supported the idea that a simple increase in physician number is not sufficient to improve patient outcomes[
There are several possible explanations for our study's findings. Patients who live further away from a cerebrovascular care center may simply be less likely to be evaluated for a cerebrovascular lesion. The most common symptom leading to discovery of unruptured cerebral aneurysms within our cohort was headache, with the majority of patients being initially evaluated by a family practitioner or a neurologist. In practices where cerebrovascular lesions are rarely encountered, vessel imaging may not be available or commonly employed in the evaluation of such a nonspecific finding. Patients living further away from a treatment center may also defer elective aneurysm treatment for logistical reasons—an unwillingness or inability to travel dozens if not hundreds of miles for the initial intervention and then for any required follow-up. Patients in our cohort who were from areas with lower median household income were also more likely to be treated after aneurysm rupture than electively, a finding which has previously been described,[
The location of the aneurysm in the circulation also significantly affected the chance of treatment after rupture in our cohort, with both posterior communicating artery lesions and anterior communicating artery lesions more than three times as likely as internal cerebral artery aneurysms to receive intervention only after hemorrhage. The dangers of posterior communicating artery aneurysms are well documented and accepted.[
Our study has several limitations. The first is its retrospective nature, which increases its vulnerability to confounders. One possible confounder is aneurysm treatment at other facilities—specifically the possibility that elective aneurysms are preferentially treated locally, while patients with subarachnoid hemorrhage are referred to high-volume centers. The literature, however, does not appear to support this, with the most recent national data suggesting that a similar percentage of unruptured and ruptured aneurysms are treated at low-volume centers.[
Socioeconomic status has been demonstrated time and again to be associated with a variety of healthcare quality measures,[
We examined a relatively small cohort of patients at a single center, thus limiting our power and the generalizability of our findings. The latter may especially be true given the nature of how healthcare providers are distributed throughout the nation. We were unable to assess the absolute incidence of unruptured aneurysms present in the population from which our hospital draws, nor do we have access to information on what proportion of these aneurysms are detected in each location. As a result, we are unable to make firm conclusions as to what impact travel distance has on rates of aneurysm diagnosis or rates of referral—only that of the cases referred to our center requiring treatment, a higher proportion of those from distant locations are treated following rupture. Finally, we did not examine specific characteristics of patients within the ruptured aneurysm group, such as time from rupture to presentation, presenting acuity (i.e., Hunt and Hess grade, World Federation of Neurological Surgeons grade), and rate of loss to follow-up. Subsequent studies examining these factors would undoubtedly be informative.
In this single-institution cohort, patients living further from our medical center were more likely to undergo treatment for their cerebral aneurysm emergently after rupture than electively. Further studies are needed to better define this association and to determine strategies to provide advanced neurosurgical care to remote regions of the country.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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