Abstract W MP42: Nationwide Database of Unruptured Cerebral Aneurysms Treated With Clipping or Coiling in Japan: The J-ASPECT Study

Abstract

Background: Evaluation of the overall clinical outcomes and health economics of stroke care is important for improving institutional quality of care. We performed a nationwide survey in Japan to analyze cases of unruptured cerebral aneurysms using the diagnostic procedure combination (DPC). Methods and Results: Certified neurosurgical training institutions in Japan provided data from the DPC database on patients hospitalized with neurosurgical diseases between April 1, 2012 and March 31, 2013. Patients hospitalized owing to unruptured cerebral aneurysms were identified from the DPC database based on the International Classification of Diseases (ICD)-10 diagnosis code (I671). We excluded patients with emergency admissions. We compared the mortality rates, modified Rankin Scale (mRS) scores, postoperative complications, and economic factors of patients who underwent clipping and coiling. With respect to postoperative complications, we evaluated the ratio of an event of complication (brain infarction, brain hemorrhage, cardiac infarction, and meningitis) and the number of complications (scored using a hospital-acquired condition). We used hierarchical logistic regression models to estimate the odds ratios (ORs) for in-hospital mortality and complications. The case volumes of clipping and coiling in each hospital were divided into quintiles, and trends were analyzed using the Cochran-Armitage trend test. We identified 5194 patients with unruptured cerebral aneurysms (3287 clipping, 1907 coiling). Patient characteristics, mortality rates, and mRS were similar between groups. Patients who underwent clipping had a significantly higher number of complications than patients who underwent coiling (β = -0.04; P = 0.03). Cases of brain infarction that had developed during hospitalization in both patients who had undergone clipping (OR = 0.28; P = 0.02) and patients who had undergone coiling (OR = 0.24; P = 0.047) were fewer in high-volume hospitals. Conclusions: Our results estimate the baseline national rates of outcomes and health and economic factors in patients with unruptured cerebral aneurysms that were treated with clipping or coiling. Our data may be useful for assessing institutional quality of care in comparison with national data.