Matsumoto Eiji, Masuzawa Toshio, Nakamura Yosikazu
Department of Surgical Neurology, Jichi Medical School, Tochigi 329-0498, Japan.
J Epidemiol. 2003 Nov;13(6):289-95. doi: 10.2188/jea.13.289.
The frequency at which unruptured cerebral aneurysms are detected has increased due to advances in low- or non-invasive diagnostic techniques. Despite the recent improvements in surgical and medical management of aneurysmal subarachnoid hemorrhages, however, the overall case-fatality rate of this disease is still high. To reduce it, the natural history of unruptured cerebral aneurysms should be better understood.
The subjects consisted of 156 patients with unruptured cerebral aneurysms who had been admitted to the Department of Surgical Neurology, Jichi Medical School Hospital or Jichi Medical School Ohmiya Medical Center, Japan, between January 1989 and December 1998. All of the patients were classified according to the process by which aneurysms had been detected. The expected number of deaths was calculated by using age- and sex-specific mortality rates obtained from the vital statistics. A standardized mortality ratio and 95% confidence interval were calculated by using the expected and observed numbers of deaths.
The standardized mortality ratios differed among the groups according to the process of detecting aneurysms. The incidence rate of rupture of unruptured cerebral aneurysms was 1.3 per 100 person-years. The annual rupture rate of unruptured cerebral aneurysms was higher than previously reported. The survival rate of the group that underwent surgical treatment for unruptured cerebral aneurysms was higher than that of the untreated group.
The annual rupture rate of unruptured cerebral aneurysms may be higher than previously reported.
由于低侵入性或非侵入性诊断技术的进步，未破裂脑动脉瘤的检出频率有所增加。然而，尽管近年来动脉瘤性蛛网膜下腔出血的手术和药物治疗有所改善，但该疾病的总体病死率仍然很高。为了降低病死率，应更好地了解未破裂脑动脉瘤的自然病史。
研究对象包括1989年1月至1998年12月期间入住日本自治医科大学医院外科神经科或自治医科大学大宫医疗中心的156例未破裂脑动脉瘤患者。所有患者均根据动脉瘤的检出过程进行分类。使用从人口动态统计中获得的年龄和性别特异性死亡率计算预期死亡人数。通过使用预期死亡人数和观察到的死亡人数计算标准化死亡率和95%置信区间。
根据动脉瘤的检出过程，各组的标准化死亡率有所不同。未破裂脑动脉瘤的破裂发生率为每100人年1.3例。未破裂脑动脉瘤的年破裂率高于先前报道。接受未破裂脑动脉瘤手术治疗的组的生存率高于未治疗组。
未破裂脑动脉瘤的年破裂率可能高于先前报道。
