Ethnic differences in risk factors for subarachnoid hemorrhage

Effect of Comorbidities on the Outcome of Patients with Aneurysmal Subarachnoid Hemorrhage: A Prospective Observational Study

Background The pathophysiological changes following aneurysmal subarachnoid hemorrhage (aSAH) lead to a varied degree of neurological deficit and cognitive decline. The presence of comorbidities can contribute to the progression and course of the disease resulting in high morbidity and mortality.

Methods A total of 140 patients with aSAH, scheduled for surgical clipping or endovascular coiling were included. The patients' comorbidities were recorded. The postoperative outcome was evaluated using Glasgow Outcome Scale at 1 month following discharge. Multiple logistic regression analysis was performed to identify variables predicting poor outcome, taking into consideration those variables which were significant in univariate analysis.

Results Sixty-six percent of these patients with aSAH had associated comorbidities. In our patient cohort, we found that smoking and hypertension were associated with worse outcome (odds ratio [OR] = 4.63 [confidence interval [CI] = 1.83–11.7] and OR = 2.92 [CI = 1.41–6.01], respectively). Hypothyroidism, diabetes mellitus, coronary artery disease, and asthma did not influence the neurological outcome because of their small number.

Conclusion Presence of comorbidities like smoking and hypertension significantly worsen the outcome of these patients with aSAH.

Decreasing Risk of Fatal Subarachnoid Hemorrhage and Other Epidemiological Trends in the Era of Coiling Implementation in Australia

BACKGROUND AND PURPOSE

Subarachnoid hemorrhage (SAH) is associated with a high risk of mortality and disability in survivors. We examined the epidemiology and burden of SAH in our population during a time services were re-organized to facilitate access to evidence-based endovascular coiling and neurosurgical care.

METHODS

SAH hospitalizations from 2001 to 2009, in New South Wales, Australia, were linked to death registrations to June 30, 2010. We assessed the variability of admission rates, fatal SAH rates and case fatality over time and according to patient demographic characteristics.

RESULTS

There were 4,945 eligible patients admitted to hospital with SAH. The risk of fatal SAH significantly decreased by 2.7% on average per year (95% CI = 0.3-4.9%). Case fatality at 2, 30, 90, and 365 days significantly declined over time. The average annual percentage reduction in mortality ranged from 4.4% for 30-day mortality (95% CI -6.1 to -2.7) (P < 0.001) to 4.7% for mortality within 2 days (-7.1 to -2.2) (P < 0.001) (Table 3). Three percent of patients received coiling at the start of the study period, increasing to 28% at the end (P-value for trend <0.001). Females were significantly more likely to be hospitalized for a SAH compared to males [incident rate ratio (IRR) = 1.33, 95% CI = 1.23-1.44] (P < 0.001) and to die from SAH (IRR = 1.40, 95% CI = 1.24-1.59) (P < 0.001). People born in South-East Asia and the Oceania region had a significantly increased risk of SAH, while the risk of fatal SAH was greater in South-East and North-East Asian born residents. People residing in areas of least disadvantage had the lowest risk of hospitalization (IRR = 0.83, 95% CI = 0.74-0.92) and also the lowest risk of fatal SAH (0.81, 95% CI = 0.66-1.00) (P < 0.001 and P = 0.003, respectively). For every 100 SAH admissions, 20 and 15 might be avoided in males and females, respectively, if the risk of SAH in our population equated to that of the most socio-economically advantaged.

CONCLUSION

Our study reports reductions in mortality risk in SAH corresponding to identifiable changes in health service delivery and evolving treatments such as coiling. Addressing inequities in SAH risk and mortality may require the targeting of prevalent and modifiable risk factors to improve population outcomes.

Methodology and reporting of meta-analyses in the neurosurgical literature

OBJECT

Neurosurgeons are inundated with vast amounts of new clinical research on a daily basis, making it difficult and time-consuming to keep up with the latest literature. Meta-analysis is an extension of a systematic review that employs statistical techniques to pool the data from the literature in order to calculate a cumulative effect size. This is done to answer a clearly defined a priori question. Despite their increasing popularity in the neurosurgery literature, meta-analyses have not been scrutinized in terms of reporting and methodology.

METHODS

The authors performed a literature search using PubMed/MEDLINE to locate all meta-analyses that have been published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Accepted checklists for reporting (PRISMA) and methodology (AMSTAR) were applied to each meta-analysis, and the number of items within each checklist that were satisfactorily fulfilled was recorded. The authors sought to answer 4 specific questions: Are meta-analyses improving 1) with time; 2) when the study met their definition of a meta-analysis; 3) when clinicians collaborated with a potential expert in meta-analysis; and 4) when the meta-analysis was the only focus of the paper?

RESULTS

Seventy-two meta-analyses were published in the JNS Publishing Group journals and Neurosurgery between 1990 and 2012. The number of published meta-analyses has increased dramatically in the last several years. The most common topics were vascular, and most were based on observational studies. Only 11 papers were prepared using an established checklist. The average AMSTAR and PRISMA scores (proportion of items satisfactorily fulfilled divided by the total number of eligible items in the respective instrument) were 31% and 55%, respectively. Major deficiencies were identified, including the lack of a comprehensive search strategy, study selection and data extraction, assessment of heterogeneity, publication bias, and study quality. Almost one-third of the papers did not meet our basic definition of a meta-analysis. The quality of reporting and methodology was better 1) when the study met our definition of a meta-analysis; 2) when one or more of the authors had experience or expertise in conducting a meta-analysis; 3) when the meta-analysis was not conducted alongside an evaluation of the authors' own data; and 4) in more recent studies.

CONCLUSIONS

Reporting and methodology of meta-analyses in the neurosurgery literature is excessively variable and overall poor. As these papers are being published with increasing frequency, neurosurgical journals need to adopt a clear definition of a meta-analysis and insist that they be created using checklists for both reporting and methodology. Standardization will ensure high-quality publications.

Epidemiology of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a form of hemorrhagic stroke that affects up to 30,000 individuals per year in the United States. The incidence of aSAH has been shown to be associated with numerous nonmodifiable (age, gender, ethnicity, family history, aneurysm location, size) and modifiable (hypertension, body mass index, tobacco and illicit drug use) risk factors. Although early repair of ruptured aneurysms and aggressive postoperative management has improved overall outcomes, it remains a devastating disease, with mortality approaching 50% and less than 60% of survivors returning to functional independence. As treatment modalities change and the percentage of minority and elderly populations increase, it is critical to maintain an up-to-date understanding of the epidemiology of SAH.