Seasonal variation in the incidence of aneurysmal subarachnoid hemorrhage in hospital- and community-based studies

2002 ◽  
Vol 96 (3) ◽  
pp. 497-509 ◽  
Author(s):  
Tetsuji Inagawa

Object. The aim of this study was to examine seasonal variations in the onset of aneurysmal subarachnoid hemorrhage (SAH) in one hospital-based and one community-based patient series. Methods. The study population consisted of 941 patients with aneurysmal SAH who were admitted to Shimane Prefectural Central Hospital and 358 patients who were treated in Izumo City, Japan. When investigated as a whole, no significant seasonal variations were found in either population; however, in both series, statistically significant seasonal trends, with a peak in winter and a nadir in summer, were found among patients aged 59 years or younger (p < 0.05 for the hospital-based series and p < 0.005 for the community-based series), but not among those aged 60 years or older, regardless of sex. In the hospital-based series, seasonal variations were most apparent at certain times of day, with significant variations observed between 8:00 a.m. and 10:00 a.m. or 8:00 a.m. and noon (p < 0.001 and p < 0.005, respectively), regardless of patient age, and between 4:00 p.m. and 6:00 p.m. for patients aged 59 years or younger (p < 0.05). Consequently, seasonal variations were significant during daytime hours (between 8:00 a.m. and 8:00 p.m., p < 0.005) but not during the night (between 8:00 p.m. and 8:00 a.m.). Similar tendencies were found in the community-based series. Among patients aged 59 years or younger who had no risk factors for SAH, these seasonal variations were significant in both series. In patients with untreated hypertension, who were current smokers and daily alcohol drinkers, however, no significant patterns were observed in either series, even among younger patients. Conclusions. In both hospital- and community-based studies, aneurysmal SAH appears to undergo seasonal variation, with a peak in winter and a nadir in summer. This seasonal pattern may be derived mainly from the occurrence of SAH in the morning, but may also be modified by patient age and SAH risk factors, resulting in the masking of significant seasonal patterns when all patients are considered together.

2000 ◽  
Vol 93 (5) ◽  
pp. 743-752 ◽  
Author(s):  
Daniel F. Kelly ◽  
Irene T. Gaw Gonzalo ◽  
Pejman Cohan ◽  
Nancy Berman ◽  
Ronald Swerdloff ◽  
...  

Object. Recognition of pituitary hormonal insufficiencies after head injury and aneurysmal subarachnoid hemorrhage (SAH) may be important, especially given that hypopituitarism-related neurobehavioral problems are typically alleviated by hormone replacement. In this prospective study the authors sought to determine the rate and risk factors of pituitary dysfunction after head injury and SAH in patients at least 3 months after insult.Methods. Patients underwent dynamic anterior and posterior pituitary function testing. Results of the tests were compared with those of 18 age-, sex-, and body mass index—matched healthy volunteers. The 22 head-injured patients included 18 men and four women (mean age 28 ± 10 years at the time of injury) with initial Glasgow Coma Scale (GCS) scores of 3 to 15. Eight patients (36.4%) had a subnormal response in at least one hormonal axis. Four were growth hormone (GH) deficient. Five patients (four men, all with normal testosterone levels, and one woman with a low estradiol level) exhibited an inadequate gonadotroph response. One patient had both GH and thyrotroph deficiency and another had both GH deficiency and borderline cortisol deficiency. At the time of injury, all eight patients with pituitary dysfunction had an initial GCS score of 10 or less and, compared with the 14 patients without dysfunction, were more likely to have had diffuse swelling, seen on initial computerized tomography scans (p < 0.05), and to have sustained a hypotensive or hypoxic insult (p = 0.07). Of two patients with SAH who were studied (Hunt and Hess Grade IV) both had GH deficiency.Conclusions. From this preliminary study, some degree of hypopituitarism appears to occur in approximately 40% of patients with moderate or severe head injury, with GH and gonadotroph deficiencies being most common. A high degree of injury severity and secondary cerebral insults are likely risk factors for hypopituitarism. Pituitary dysfunction also occurs in patients with poor-grade aneurysms. Postacute pituitary function testing may be warranted in most patients with moderate or severe head injury, particularly those with diffuse brain swelling and those sustaining hypotensive or hypoxic insults. The neurobehavioral effects of GH replacement in patients suffering from head injury or SAH warrant further study.


2005 ◽  
Vol 102 (2) ◽  
pp. 194-201 ◽  
Author(s):  
Seppo Juvela ◽  
Jari Siironen ◽  
Joona Varis ◽  
Kristiina Poussa ◽  
Matti Porras

Object. The aim of this study was to test whether enoxaparin treatment (40 mg subcutaneously once daily) reduces the risk of cerebral infarction after subarachnoid hemorrhage (SAH) and to investigate predictive risk factors for permanent ischemic lesions visible on follow-up computerized tomography (CT) scans obtained 3 months after SAH. Methods. After undergoing surgery for a ruptured aneurysm, 170 patients were randomized in a prospective, double-blind, placebo-controlled trial to test the effect of enoxaparin on the occurrence of ischemic lesions, which were demonstrated on follow-up CT scans available for 156 patients. The presence of lesions correlated highly with an impaired outcome, as assessed using both the Glasgow Outcome and modified Rankin Scales (p < 0.01). Lesions occurred in 101 (65%) of the 156 patients. In half of the patients (51 patients) no lesion was visible on the CT scan obtained on the 1st postoperative day in 51 patients. On univariate analysis, the presence of lesions at 3 months post-SAH was not associated with enoxaparin treatment but did correlate with several clinical, radiological, and prehemorrhage variables. Significant independent risk factors for lesions consisted of an impaired initial clinical condition (odds ratio [OR] 2.63, 95% confidence interval [CI] 1.03–6.73), amount of subarachnoid blood (OR 6.51, 95% CI 2.27–18.65), nocturnal occurrence of SAH (that is, between 12:01 a.m. and 8:00 a.m.; OR 4.32, 95% CI 1.28–14.52), fixed symptoms of delayed ischemia (OR 5.21, 95% CI 1.02–26.49), duration of temporary artery occlusion during surgery (OR 1.66 per minute, 95% CI 1.20–2.31), and body mass index (OR 1.13/kg/m2, 95% CI 1.01–1.28). Conclusions The presence of ischemic lesions can be predicted by the severity of bleeding, delayed cerebral ischemia, excess weight, duration of temporary artery occlusion, and occurrence of nocturnal aneurysm rupture.


2004 ◽  
Vol 101 (2) ◽  
pp. 255-261 ◽  
Author(s):  
Christopher Reilly ◽  
Chris Amidei ◽  
Jocelyn Tolentino ◽  
Babak S. Jahromi ◽  
R. Loch Macdonald

Object. This study was conducted for two purposes. The first was to determine whether a combination of measurements of subarachnoid clot volume, clearance rate, and density could improve prediction of which patients experience vasospasm. The second was to determine if each of these three measures could be used independently to predict vasospasm. Methods. Digital files of the cranial computerized tomography (CT) scans obtained in 75 consecutive patients admitted within 24 hours of subarachnoid hemorrhage (SAH) were analyzed in a blinded fashion by an observer who used quantitative imaging software to measure the volume of SAH and its density. Clot clearance rates were measured by quantifying SAH volume on subsequent CT scans. Vasospasm was defined as new onset of a focal neurological deficit or altered consciousness 5 to 12 days after SAH in the absence of other causes of deterioration, diagnosed with the aid of or exclusively by confirmatory transcranial Doppler ultrasonography and/or cerebral angiography. Univariate analysis showed that vasospasm was significantly associated with the SAH grade as classified on the Fisher scale, the initial clot volume, initial clot density, and percentage of clot cleared per day (p < 0.05). In multivariate analysis, initial clot volume and percentage of clot cleared per day were significant predictors of vasospasm (p < 0.05), whereas Fisher grade and initial clot density were not. Conclusions. Quantitative analysis of subarachnoid clot shows that vasospasm is best predicted by initial subarachnoid clot volume and the percentage of clot cleared per day.


2003 ◽  
Vol 98 (4) ◽  
pp. 807-811 ◽  
Author(s):  
Anan Bedavanija ◽  
Jürgen Brieger ◽  
Hans-Anton Lehr ◽  
Jan Maurer ◽  
Wolf J. Mann

Object. Acoustic neuroma is the most frequent benign tumor of the cerebellopontine angle, and surgery is still the most common form of treatment. To gain better insight into the dysregulated mechanisms causing growth of acoustic neuroma, the authors studied the proliferative activity of 34 consecutive samples by analyzing immunohistochemical staining with Ki-67 and proliferating cell nuclear antigen (PCNA), and apoptosis based on the terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling. Data from these analyses were correlated with clinical parameters (that is, tumor size, duration of symptoms, and patient age). Methods. Apoptotic cells were found in none of the tumors. Proliferation measured on staining with Ki-67 and PCNA correlated with tumor size, but not with patient age or duration of symptoms. The authors demonstrated that tumors 18 mm or smaller in diameter have lower proliferation indices and growth rates, compared with tumors larger than 18 mm with high proliferative indices and growth rates. Additionally, they observed that these more aggressive, larger tumors occur mostly in patients younger than 50 years of age. Conclusions. Patients with tumors larger than 18 mm in diameter and who are younger than 50 years of age sustain an enhanced risk for fast-growing tumors because of these lesions' enhanced proliferative activity. For these patients the authors recommend active therapy.


2001 ◽  
Vol 95 (3) ◽  
pp. 393-401 ◽  
Author(s):  
Tõnu Rätsep ◽  
Toomas Asser

Object. In this study the authors evaluated the relative role of cerebral hemodynamic impairment (HDI) in the pathogenesis of delayed cerebral ischemia and poor clinical outcome after aneurysmal subarachnoid hemorrhage (SAH). Methods. Cerebral hemodynamics were assessed daily with transcranial Doppler (TCD) ultrasonography in 55 consecutive patients with verified SAH. Hemodynamic impairment was defined as blood flow velocity (BFV) values consistent with vasospasm in conjunction with impaired autoregulatory vasodilation as evaluated using the transient hyperemic response tests in the middle cerebral arteries. A total of 1344 TCD examinations were performed, in which the evaluation of HDI was feasible during 80.9% and HDI was registered during 12% of the examinations. It was found that HDI occurred in 60% of patients and was frequently recorded in conjunction with severe vasospasm (p < 0.05) and a rapid increase of BFV values (p < 0.05). Detection of HDI was closely associated with the development of delayed ischemic brain damage after SAH (p < 0.05). Furthermore, because delayed ischemia was never observed in cases in which vasospasm had not led to the development of HDI, its occurrence increased significantly the likelihood of subsequent cerebral ischemia among the patients with vasospasm (p < 0.05). Detection of HDI was independently related to unfavorable clinical outcome according to Glasgow Outcome Scale at 6 months after SAH (p < 0.05). Conclusions. The results showed that HDI is common after SAH and can be evaluated with TCD ultrasonography in routine clinical practice. Detection of HDI could be useful for identifying patients at high or low risk for delayed ischemic complications and unfavorable clinical outcome after SAH.


2003 ◽  
Vol 99 (6) ◽  
pp. 953-959 ◽  
Author(s):  
Jari Siironen ◽  
Seppo Juvela ◽  
Joona Varis ◽  
Matti Porras ◽  
Kristiina Poussa ◽  
...  

Object. From the moment an intracranial aneurysm ruptures, cerebral blood flow is impaired, and this impairment mainly determines the outcome in patients who survive after the initial bleeding. The exact mechanism of impairment is unknown, but activation of coagulation and fibrinolysis correlate with clinical condition and outcome after aneurysmal subarachnoid hemorrhage (SAH). The purpose of this study was to determine whether enoxaparin, a low-molecular-weight heparin, which is a well-known anticoagulating agent, has any effect on the outcome of aneurysmal SAH postoperatively. Methods. In this randomized, double-blind, single-center clinical trial, 170 patients (85 per group) with aneurysmal SAH were randomly assigned to receive either enoxaparin (40 mg subcutaneously once daily) or a placebo, starting within 24 hours after occlusion of the aneurysm and continuing for 10 days. Analysis was done on an intention-to-treat basis. Outcome was assessed at 3 months on both the Glasgow Outcome and modified Rankin Scales. Patients were eligible for the study if surgery was performed within 48 hours post-SAH, and no intracerebral hemorrhage was larger than 20 mm in diameter on the first postoperative computerized tomography scan. At 3 months, there were no significant differences in outcome by treatment group. Of the 170 patients, 11 (6%) died, and only 95 (56%) had a good outcome. Principal causes of unfavorable outcome were poor initial condition, delayed cerebral ischemia, and surgical complications. There were four patients with additional intracranial bleeding in the group receiving enoxaparin. The bleeding was not necessarily associated with the treatment itself, nor did it require treatment, and there were no such patients in the placebo group. Conclusions. Enoxaparin seemed to have no effect on the outcome of aneurysmal SAH in patients who had already received routine nimodipine and who had received triple-H therapy when needed. Routine use of low-molecular-weight heparin should be avoided during the early postoperative period in patients with SAH, because this agent seems to increase intracranial bleeding complications slightly, with no beneficial effect on neurological outcome.


2000 ◽  
Vol 93 (6) ◽  
pp. 967-975 ◽  
Author(s):  
Tetsuji Inagawa ◽  
Masaaki Shibukawa ◽  
Futoshi Inokuchi ◽  
Yoshio Tokuda ◽  
Yoshikazu Okada ◽  
...  

Object. The purpose of this study was to assess the overall management and surgical outcome of primary intracerebral hemorrhage (ICH) and aneurysmal subarachnoid hemorrhage (SAH) among the 85,000 residents of Izumo City, Japan.Methods. During 1991 through 1996, 267 patients with ICH and 123 with SAH were treated in Izumo. Of the 267 patients with ICH, 25 underwent hematoma removal by open craniotomy or suboccipital craniectomy and 34 underwent stereotactic evacuation of the hematoma, whereas aneurysm clipping was performed in 71 of the 123 patients with SAH; operability rates were thus 22% for ICH and 58% for SAH (p < 0.0001). The overall 30-day survival rates were 86% for ICH and 66% for SAH (p < 0.0001) and the 2-year survival rates were 73% and 62% (p = 0.0207), respectively. In patients who underwent surgery, 30-day and 2-year survival rates were 93% for ICH and 100% for SAH (p = 0.0262), and 75% for ICH and 97% for SAH (p = 0.0002), respectively. In patients with ICH, the most important predictors of 30-day case-fatality rates were the volume of the hematoma, the Glasgow Coma Scale (GCS) score, rebleeding, and midline shifting, whereas those for 2-year survival were the GCS score, age, rebleeding, and hematoma volume. In patients with SAH, the most important determinants of 30-day case-fatality rates were the GCS score and age, whereas only the GCS score had a significant impact on 2-year survival.Conclusions. The overall survival rates for patients with ICH or SAH in Izumo were more favorable than those in previously published epidemiological studies. However, despite improved surgical results, the overall management of ICH and SAH still produced an unsatisfactory outcome, mainly because of primary brain damage.


1981 ◽  
Vol 54 (2) ◽  
pp. 141-145 ◽  
Author(s):  
Harold P. Adams ◽  
Neal F. Kassell ◽  
James C. Torner ◽  
Donald W. Nibbelink ◽  
Adolph L. Sahs

✓ The overall results are presented of early medical management and delayed operation among 249 patients studied during the period 1974 to 1977, treated within 3 days of subarachnoid hemorrhage (SAH) and evaluated 90 days after aneurysm rupture. The results included 36.2% mortality, 17.9% survival with serious neurological sequelae, and 46% with a favorable outcome. Of the patients admitted in good neurological condition, 28.7% had died and only 55.7% had a favorable recovery at 90 days after SAH. These figures represent the results despite effective reduction in early rebleeding by antifibrinolytic therapy and successful surgery in those patients reaching operation. Further therapeutic advances are needed for patients hospitalized within a few days after SAH.


2004 ◽  
Vol 100 (1) ◽  
pp. 8-15 ◽  
Author(s):  
Jane Skjøth-Rasmussen ◽  
Mette Schulz ◽  
Soren Risom Kristensen ◽  
Per Bjerre

Object. In the treatment of patients with aneurysmal subarachnoid hemorrhage (SAH), early occlusion of the aneurysm is necessary as well as monitoring and treatment of complications following the primary bleeding episode. Monitoring with microdialysis has been studied for its ability to indicate and predict the occurrence of delayed ischemic neurological deficits (DINDs) in patients with SAH. Methods. In 42 patients with aneurysmal SAH microdialysis monitoring of metabolites was performed using a 0.3-µl/minute perfusion flow over several days, and the results were correlated to clinical events and to brain infarction observed on computerized tomography scans. The microdialysis probe was inserted into the territory of the parent artery of the aneurysm. The authors defined an ischemic pattern as increases in the lactate/glucose (L/G) and lactate/pyruvate (L/P) ratios that were greater than 20% followed by a 20% increase in glycerol concentration. This ischemic pattern was found in 17 of 18 patients who experienced a DIND and in three of 24 patients who did not experience a delayed clinical deterioration. The ischemic pattern preceded the occurrence of a DIND by a mean interval of 11 hours. Maximum L/G and L/P ratios did not correlate with the presence of DIND or outcome, and there was no association between the glycerol level and subsequent brain infarction. Conclusions. Microdialysis monitoring of the cerebral metabolism in patients with SAH may predict with high sensitivity and specificity the occurrence of a DIND. Whether an earlier diagnosis results in better treatment of DINDs and, therefore, in overall better outcomes remains to be proven, as it is linked to an efficacious treatment of cerebral vasospasm.


2002 ◽  
Vol 97 (6) ◽  
pp. 1302-1305 ◽  
Author(s):  
Takao Kamezaki ◽  
Kiyoyuki Yanaka ◽  
Sohji Nagase ◽  
Keishi Fujita ◽  
Noriyuki Kato ◽  
...  

Object. Cerebral vasospasm remains a devastating medical complication of aneurysmal subarachnoid hemorrhage (SAH). Reactive oxygen species and subsequent lipid peroxidation are reported to participate in the causes of cerebral vasospasm. This clinical study was performed to investigate the relationships between levels of lipid peroxides in cerebrospinal fluid (CSF) and both delayed cerebral vasospasm and clinical outcome after SAH. Methods. Levels of phosphatidylcholine hydroperoxide (PCOOH) and cholesteryl ester hydroperoxide (CEOOH) in the CSF were measured in 20 patients with aneurysmal SAH. The patients' CSF was collected within 48 hours of hemorrhage onset and on Day 6 or 7 post-SAH. On Day 7, angiography was performed to verify the degree and extent of the vasospasm. The relationship between the patients' clinical profiles and the levels of lipid peroxides in the CSF were investigated. Both PCOOH and CEOOH were detectable in CSF, and their levels decreased within 7 days after onset of SAH. The levels of CEOOH within 48 hours after onset of hemorrhage were significantly higher in patients in whom symptomatic vasospasm later developed than in patients in whom symptomatic vasospasm did not develop (p = 0.002). Levels of PCOOH measured within 48 hours after onset of hemorrhage were significantly higher in patients with poor outcomes than in patients with good outcomes (p = 0.043). Conclusions. Increased levels of lipid peroxides measured in the CSF during the acute stage of SAH were predictive of both symptomatic vasospasm and poor outcome. Measurements of lipid peroxides in the CSF may be useful prognostically for patient outcomes as well as for predicting symptomatic vasospasm.


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