Epidemiology Of Subarachnoid Hemorrhage Research Articles

Abstract TP1: Changing Trends in the Epidemiology of Subarachnoid Hemorrhage: A Population-Based Study

Background: There are conflicting data on temporal trends in subarachnoid hemorrhage (SAH) incidence and outcomes. We examined trends from 1993-2020 in a long-running population-based stroke study conducted in the Greater Cincinnati Northern Kentucky (GCNK) region. Methods: Using a well-validated approach, we ascertained all incident nontraumatic SAHs among residents of the GCNK region in the following study periods; July 1993-June 94, calendar years 1999, 2005, 2010, 2015, and 2020. Potential cases were identified by ICD codes, abstracted, and then adjudicated by physicians. Aneurysmal SAH (aSAH) was defined as those with culprit aneurysms; cases with no available vessel imaging were considered aSAH if the hemorrhage volume was “massive” or if the patient died rapidly after onset. Incidence rates were compared over time using linear regression after normalizing to 2010 census demographics. The primary outcome assessed was unadjusted 30-day Case Fatality Rate (CFR), which was available through 2015. Results: We identified 518 SAH cases, of which 372 were aSAH (71.8%). Overall SAH incidence rate was stable over time, ranging from 8-10 cases per 100,000 person-years (Figure Panel A); however, the rate of aSAH showed a statistically significant decline, going from 7.2 cases/100,000 person-years in 1993 to 5.2 cases/100,000 person-years in 2020 (trend P =0.02). There was a nonsignificant increase in nonaneurysmal SAH ( P =0.09 for trend). Overall 30-day CFR declined significantly through 2015 ( P =0.006, Figure Panel B), driven predominantly by a decline in aSAH CFR (from 39.3% to 23.7%, trend P =0.04). Conclusion: We observed a significant decline in the incidence of aSAH from 1993-2020; however, overall SAH incidence was stable in the setting of numerically more nonaneurysmal SAHs. Further study is needed to understand the causes of this trend. 30-Day CFR has significantly improved both for overall SAH and for aSAH.

Epidemiology of Subarachnoid Hemorrhage in Isolated Islands in Japan: A Population-based Study in the Miyako Islands.

The Miyako Islands (with a population of approximately 50,000) are located in southwestern Japan, with a subtropical oceanic climate. This isolated location permitted a retrospective population-based epidemiological study of subarachnoid hemorrhage. We retrospectively enrolled 110 consecutive patients from 2010 to 2019 using the subarachnoid hemorrhage database at Okinawa Miyako Hospital, which is the only local facility with neurosurgeons. We calculated the incidence of subarachnoid hemorrhage standardized to the entire Japanese population. The seasonal distribution of subarachnoid hemorrhage onset and patients' epidemiological characteristics were also investigated. The standardized annual incidence of subarachnoid hemorrhage was 21.4 per 100,000 population, as reported previously in Japan. The patients' mean age was 62.1 ± 15.4 years, and women constituted 60.9%. Anterior communicating artery aneurysms were most common. The endovascular treatment for ruptured aneurysms was increasing as standard levels in Japan. The rates of symptomatic vasospasm and secondary hydrocephalus requiring additional neurosurgical treatment were 2.7% and 19.1%, respectively. The mortality rate was 23.6%. The percentage of patients with a modified Rankin scale score of 0-2 at discharge was 55.5%. There were no differences in the frequency of subarachnoid hemorrhage associated with seasonal distribution or climatic factors. The incidence, baseline characteristics, and clinical outcomes of subarachnoid hemorrhage in the Miyako Islands were similar to those in other regions of Japan. There are preferable epidemiological backgrounds for further practical clinical research.

Epidemiology of Subarachnoid Hemorrhage, Patterns of Management, and Outcomes in China: A Hospital‐Based Multicenter Prospective Study

To conduct a large-scale analysis on epidemiology, management, and outcomes of spontaneous subarachnoid hemorrhage (SAH), and to investigate the current situation of aneurysm obliteration in China. A multicenter prospective cohort study involving 132 hospitals throughout China from September 2007 to August 2008 was conducted. A total of 651 patients with spontaneous SAH were evaluated. The most frequent type of SAH was aneurysmal SAH (77.4%), followed by uncommon causes (17.5%) and uncertain etiologies (5.1%). For aneurysmal SAH, the cumulative mortality at 28days, 3months, 6months, and 12months was 16.9%, 21.2%, 23.6%, and 24.6%, respectively. Obliteration of aneurysms, age, Hunt and Hess grade, and history of stroke affected the 12-month mortality. In multiple regression analysis, the region, type of hospital, patient's age, history of hypertension, and nonintraventricular hemorrhage impacted aneurysm obliteration. Aneurysmal rupture is the most common cause of spontaneous SAH in China. The percentage of aneurysm obliteration is still low in China that seems to contribute to long-term mortality. With continued training of specialists, proper allocation of healthcare resources, and establishment of stroke centers, the rate of securing aneurysms is expected to rise.

Epidemiology of subarachnoid hemorrhage in the Yaeyama Islands, an isolated subtropical region of Japan most frequently affected by typhoons: A population-based study

ObjectiveThe present study analyzed epidemiological data for patients with subarachnoid hemorrhage (SAH) in a subtropical region of Japan that is the most frequently affected by typhoons. Patients and methodsThe medical records of hospitalized patients who had been diagnosed as having SAH at Okinawa Prefectural Yaeyama Hospital during a 13-year period were reviewed. Demographic and epidemiological data including date and time of onset and activity at onset and clinical data were collected. Meteorological data for typhoon's approaches to the Yaeyama Islands were obtained from the web-site of the Japan Meteorological Agency. In addition, patients who had developed SAH during a period of 3days before and after the closest approach of a typhoon (CAT) were examined. ResultsA total of 94 patients were identified. A monthly peak in August, a weekly peak on Monday, and two daily peaks in the evening and morning were observed. The incidence of SAH during a period of 3days before and after the CAT was approximately twice as high as that on other days, and a statistically significant difference was found. ConclusionPeriodic patterns of SAH onset revealed unusual monthly and circaseptan variations and the usual circadian variation. SAH onset was associated with typhoon's approaches.

八重山諸島におけるクモ膜下出血の疫学的検討

八重山諸島におけるクモ膜下出血の疫学的検討

Subarachnoid Hemorrhage: Medical and Surgical Management

Subarachnoid Hemorrhage: Medical and Surgical Management edited by Takehiko Yanagihara, David G. Piepgras, and John L.D. Atkinson , 584 pp., ill., New York, Marcel Dekker, 1998, $195.00 This multiauthored textbook on subarachnoid hemorrhage and its management includes 18 chapters on topics such as animal models of subarachnoid hemorrhage and vasospasm, epidemiology of subarachnoid hemorrhage, intracranial …