Treatment of Ruptured and Unruptured Cerebral Aneurysms
Background Integration of data from clinical trials and advancements in technology predict a change in selection for treatment of patients with cerebral aneurysm.
Objective To describe patterns of use and in-hospital mortality associated with surgical and endovascular treatments of cerebral aneurysms over the past decade.
Materials and methods The data are 34 899 hospital discharges with a diagnosis of ruptured or unruptured cerebral aneurysm from 1998 to 2007 identified from the Nationwide Inpatient Sample (NIS). The rates of endovascular coiling and surgical clipping and in-hospital mortality among patients with an aneurysm are examined over a decade by hospital and patient demographic characteristics.
Results From 1998 to 2007, 20 134 discharges with a ruptured aneurysm and 14 765 discharges with an unruptured aneurysm were identified. Over this decade, the number of patients discharged with a ruptured aneurysm was stable while the number discharged with an unruptured aneurysm increased significantly. The use of endovascular coiling increased at least twofold for both groups of patient (p<0.001) with the majority of unruptured aneurysms treated with coiling by 2007. Although whites were more likely than non-whites to undergo coiling versus clipping for a ruptured aneurysm (OR=1.30; 95% CI 1.13 to 1.48) and men with unruptured aneurysms were more likely than women to undergo coiling (OR=1.26; 95% CI 1.13 to 1.40), by 2007 differences in treatment selection by gender and racial subgroups were decreased or statistically non-significant. Over time the use of coiling spread from primarily large, teaching hospitals to smaller, non-teaching hospitals.
Conclusions The majority of unruptured aneurysms in the USA are now treated with endovascular coiling. Although surgical clipping is used for treatment of most ruptured aneurysms, its use is decreasing over time. Dissemination of endovascular procedures appears widespread across patient and hospital subgroups.
Cerebral aneurysms are estimated to affect approximately 2% of the population worldwide. Rupture of a cerebral aneurysm results in subarachnoid hemorrhage (SAH) and is associated with substantial mortality and morbidity. The rupture rate of an aneurysm is thought to vary with its size, location and morphological characteristicss as well as a patient's personal and family medical history, and these variables help to guide the clinical management of these lesions. For those aneurysms requiring treatment, two primary methods are used: microsurgical clipping or endovascular coiling. In 2002, outcomes for patients with ruptured cerebral aneurysms were reported in the International Subarachnoid Aneurysm Trial (ISAT), a randomized, controlled clinical trial that compared the mortality and clinical outcomes of patients with aneurysmal SAH treated with either surgical clipping or endovascular coiling. The study reported that patients who underwent coiling had lower mortality and better outcome at 1 year than those who had open surgery. As a result of this trial, a change in practice pattern within the USA was likely with more ruptured aneurysms treated endovascularly. Although a previous effort to assess this trend through 2003 was presented by Andaluz et al (2008), only now has sufficient time passed since the publication of the ISAT trial results to allow for a formal examination of treatment practice patterns for cerebral aneurysms, both ruptured and unruptured, within the USA. In addition, use of coiling may not be uniform for patients in different demographic subgroups and in hospitals located in different geographic areas. Using data from the Nationwide Inpatient Sample (NIS), we present trends in treatment selection for patients with cerebral aneurysms over the past decade and the associated clinical outcomes.
Abstract and Introduction
Abstract
Background Integration of data from clinical trials and advancements in technology predict a change in selection for treatment of patients with cerebral aneurysm.
Objective To describe patterns of use and in-hospital mortality associated with surgical and endovascular treatments of cerebral aneurysms over the past decade.
Materials and methods The data are 34 899 hospital discharges with a diagnosis of ruptured or unruptured cerebral aneurysm from 1998 to 2007 identified from the Nationwide Inpatient Sample (NIS). The rates of endovascular coiling and surgical clipping and in-hospital mortality among patients with an aneurysm are examined over a decade by hospital and patient demographic characteristics.
Results From 1998 to 2007, 20 134 discharges with a ruptured aneurysm and 14 765 discharges with an unruptured aneurysm were identified. Over this decade, the number of patients discharged with a ruptured aneurysm was stable while the number discharged with an unruptured aneurysm increased significantly. The use of endovascular coiling increased at least twofold for both groups of patient (p<0.001) with the majority of unruptured aneurysms treated with coiling by 2007. Although whites were more likely than non-whites to undergo coiling versus clipping for a ruptured aneurysm (OR=1.30; 95% CI 1.13 to 1.48) and men with unruptured aneurysms were more likely than women to undergo coiling (OR=1.26; 95% CI 1.13 to 1.40), by 2007 differences in treatment selection by gender and racial subgroups were decreased or statistically non-significant. Over time the use of coiling spread from primarily large, teaching hospitals to smaller, non-teaching hospitals.
Conclusions The majority of unruptured aneurysms in the USA are now treated with endovascular coiling. Although surgical clipping is used for treatment of most ruptured aneurysms, its use is decreasing over time. Dissemination of endovascular procedures appears widespread across patient and hospital subgroups.
Introduction
Cerebral aneurysms are estimated to affect approximately 2% of the population worldwide. Rupture of a cerebral aneurysm results in subarachnoid hemorrhage (SAH) and is associated with substantial mortality and morbidity. The rupture rate of an aneurysm is thought to vary with its size, location and morphological characteristicss as well as a patient's personal and family medical history, and these variables help to guide the clinical management of these lesions. For those aneurysms requiring treatment, two primary methods are used: microsurgical clipping or endovascular coiling. In 2002, outcomes for patients with ruptured cerebral aneurysms were reported in the International Subarachnoid Aneurysm Trial (ISAT), a randomized, controlled clinical trial that compared the mortality and clinical outcomes of patients with aneurysmal SAH treated with either surgical clipping or endovascular coiling. The study reported that patients who underwent coiling had lower mortality and better outcome at 1 year than those who had open surgery. As a result of this trial, a change in practice pattern within the USA was likely with more ruptured aneurysms treated endovascularly. Although a previous effort to assess this trend through 2003 was presented by Andaluz et al (2008), only now has sufficient time passed since the publication of the ISAT trial results to allow for a formal examination of treatment practice patterns for cerebral aneurysms, both ruptured and unruptured, within the USA. In addition, use of coiling may not be uniform for patients in different demographic subgroups and in hospitals located in different geographic areas. Using data from the Nationwide Inpatient Sample (NIS), we present trends in treatment selection for patients with cerebral aneurysms over the past decade and the associated clinical outcomes.