Sex differences in stroke case fatality: a meta‐analysis

Emergency stroke care has become a natural part of the emerging discipline of neurocritical care and demands close cooperation between the neurologist and neurointerventionists, neurosurgeons, and anesthesiologists. Endovascular treatment (EVT), including intra‐arterial thrombolysis, mechanical thrombectomy and angioplasty/stenting, is under rapid development. Although EVT has yet to be shown in randomized controlled trials to improve clinical outcome compared to intravenous thrombolysis, it is far better in achieving recanalization of occluded large cerebral vessels, which is crucial for rescuing the penumbra. Moreover, decompressive craniectomy is now a well‐established treatment option for malignant middle cerebral artery infarction and cerebellar stroke. Using a case‐based approach, this article reviews recent achievements in advanced treatment options for patients with acute ischemic stroke.     

Fever is associated with doubling of odds of short‐term mortality in ischemic stroke: an updated meta‐analysis

Prasad K, Krishnan PR. Fever is associated with doubling of odds of short‐term mortality in ischemic stroke: an updated meta‐analysis.
Acta Neurol Scand: 2010: 122: 404–408.
© 2010 The Authors Journal compilation © 2010 Blackwell Munksgaard. Objective – Association between fever and ischemic stroke mortality is known, but the magnitude and independence of the association is controversial. This paper aims to determine the size of independent effect of fever on short term mortality in acute ischemic stroke. Methods – We searched the Medline and Cochrane library databases for papers studying the relationship between fever in acute ischemic stroke and short term mortality from January, 1990 to November, 2008. Two authors independently selected the studies for inclusion in the review using explicit criteria. Data was entered into software Revman 4.2.8. Heterogeneity was assessed using I² and chi‐square statistics. Odds ratios (OR) from logistic regression were combined. Magnitude of association was determined using meta‐analysis of the adjusted odds ratio using fixed effects model. Results – Six cohort studies involving 2986 patients were included. There was no significant heterogeneity among studies reporting short‐term mortality (I² = 21.2%, P = 0.28). Meta‐analysis yielded a combined OR of 2.20 (95% CI 1.59–3.03, P < 0.00001). Conclusions – This meta‐analysis suggests that fever within first 24 h of hospitalization in patients with ischemic stroke is associated with doubling of odds of mortality within one month of the onset of stroke.     

High‐dose statin therapy and risk of intracerebral hemorrhage: a meta‐analysis

Statin plays a major role in the primary and secondary prevention of cardiovascular disease (CVD). Inconsistent findings in the studies have been observed toward the risk of intracerebral hemorrhage (ICH) using higher dose of statin. To examine this issue, we performed a meta‐analysis of randomized controlled trials (RCTs) to assess the association between higher dose of various statins and risk of ICH among patients with CVD. Literature was searched for studies published before June 10, 2015, using electronic database ‘PubMed’, ‘EMBASE’, and ‘Google Scholar’ as well as from many trial databases. The following search terms were used: ‘Statin therapy’ AND ‘Cardiovascular Disease’, AND ‘Dose’ AND ‘Intracerebral hemorrhage’, AND ‘Randomized Controlled Trials’ AND ‘High Dose Statin’. High dose of statins was defined as atorvastatin 80 mg, simvastatin 80 mg, pravastatin 40 mg, rosuvastatin 20 mg per day. Fixed‐effect model was used to estimate the risk ratio (RR) and 95% confidence interval (CI) if heterogeneity was <50%; otherwise, random‐effect model was used. Begg's funnel plot was used to assess the publication bias. Seven RCTs involving 31,099 subjects receiving high‐dose statin and 31,105 subjects receiving placebo were analyzed in our meta‐analysis. A significant risk of ICH was observed in subjects with higher dose of statin (RR = 1.53; 95% CI: 1.16–2.01; P = 0.002). There was no difference in all‐cause mortality between the two groups (RR = 0.95; 95% CI: 0.86–1.06; P = 0.36). No publication bias was observed through Begg's funnel plot. Higher dose of statins was found to be associated with the risk of ICH. Future studies are needed to confirm these findings.     

Parkinson's disease and risk of mortality: meta‐analysis and systematic review

To evaluate the existing prospective observational studies on the morality risk among Parkinson's disease (PD) patients and determine the overall risk ratio (RR) of mortality by conducting a meta‐analysis and systematic review. Original articles published in English were searched in PubMed and Embase databases prior to March 2013. Only prospective observational studies providing adjusted risk estimates related to PD and future mortality were considered eligible. Pooled adjusted RR and 95% confidence interval (CI) were computed either by fixed‐effects models or by random‐effects models. Eight studies with 72,833 participants were identified and analysed. In the pooled analyses, patients with PD had a greater risk of all‐cause mortality (RR = 2.22; 95% CI: 1.78–2.77). Subgroup analyses based on the design, gender, follow‐up duration and sample size showed that a consistent positive association between PD and the mortality risk in each subgroup. However, no statistical significance was found for the baseline age <65 years (RR = 1.42; 95% CI: 0.72–2.77). PD patients with dementia had particularly high mortality risks (RR = 3.78; 95% CI: 2.06–6.92). This meta‐analysis indicated that among patients with PD, the all‐cause mortality increased by 2.22‐fold compared with the general population. PD patients with dementia particularly had higher risks of mortality.     

Clozapine as a first‐ or second‐line treatment in schizophrenia: a systematic review and meta‐analysis

Objective

No consensus exists on whether clozapine should be prescribed in early stages of psychosis. This systematic review and meta‐analysis therefore focus on the use of clozapine as first‐line or second‐line treatment in non‐treatment‐resistant patients.

Methods

Articles were eligible if they investigated clozapine compared to another antipsychotic as a first‐ or second‐line treatment in non‐treatment‐resistant schizophrenia spectrum disorders (SCZ) patients and provided data on treatment response. We performed random‐effects meta‐analyses.

Results

Fifteen articles were eligible for the systematic review (N = 314 subjects on clozapine and N = 800 on other antipsychotics). Our meta‐analysis comparing clozapine to a miscellaneous group of antipsychotics revealed a significant benefit of clozapine (Hedges’ g = 0.220, P = 0.026, 95% CI = 0.026–0.414), with no evidence of heterogeneity. In addition, a sensitivity analysis revealed a significant benefit of clozapine over risperidone (Hedges’ g = 0.274, P = 0.030, 95% CI = 0.027–0.521).

Conclusion

The few eligible trials on this topic suggest that clozapine may be more effective than other antipsychotics when used as first‐ or second‐line treatment. Only large clinical trials may comprehensively probe disease stage‐dependent superiority of clozapine and investigate overall tolerability.     

Prenatal,perinatal and neonatal risk factors for perinatal arterial ischaemic stroke: a systematic review and meta‐analysis

The aim of the present study was to perform a meta‐analysis of published data to determine the significance of clinical factors and exposures to the risk of perinatal arterial ischaemic stroke (PAIS) and provide guidance for clinical diagnosis and treatment. A comprehensive literature search of the PubMed, Embase, MEDLINE and Cochrane Library databases for relevant observational studies (cohort/case?control) from March 1984 to March 2016 was undertaken. Two review authors independently examined the full text records to determine which studies met the inclusion criteria and evaluated risk factors for PAIS. Risk ratios, odds ratios and 95% confidence intervals were estimated. A total of 11 studies were included in the analyses. Intrapartum fever >38°C, pre‐eclampsia, oligohydramnios, primiparity, forceps delivery, vacuum delivery, fetal heart rate abnormalities, abnormal cardiotocography tracing, cord abnormalities, birth asphyxia, emergency caesarean section, tight nuchal cord, meconium‐stained amniotic fluid, umbilical arterial pH <7.10, Apgar score at 5 min <7, resuscitation at birth, hypoglycaemia, male gender and small for gestational age were identified as risk factors for PAIS. This systemic review and meta‐analysis provides a preliminary evidence‐based assessment of the risk factors for PAIS. Patients with any of the risk factors identified in this analysis should be given careful consideration to ensure the prevention of PAIS. Future studies focusing on the combined effects of multiple prenatal, perinatal and neonatal risk factors for PAIS are warranted.     

Allergy and risk of glioma: a meta‐analysis

We evaluated the association between allergic conditions and the risk of glioma in case–control and cohort studies published so far on this issue. A total of 12 studies (10 case–control and 2 cohort studies) were included in the analysis, involving 61 090 participants, of whom 6408 had glioma. When compared with non‐allergic conditions, the pooled odds ratio (OR) with any allergic conditions for glioma was 0.60 (95% CI: 0.52–0.69, P < 0.001), suggesting a significant negative association (protective effect) between allergy and glioma. Subgroup analysis showed that the ORs were 0.70 (95% CI: 0.62–0.79, P < 0.001), 0.69 (95% CI: 0.62–0.78, P < 0.001), and 0.78 (95% CI: 0.70–0.87, P < 0.001) for asthma, eczema, and hay fever, respectively. The significant association remained even after excluding the bias of proxy reporting (OR = 0.61; 95% CI: 0.50–0.75, P < 0.001). We conclude that allergic conditions may significantly reduce the risk of glioma.     

Non‐invasive brain stimulation for fine motor improvement after stroke: a meta‐analysis

The aim of this study was to determine whether non‐invasive brain stimulation (NIBS) techniques improve fine motor performance in stroke. We searched PubMed, EMBASE, Web of Science, SciELO and OpenGrey for randomized clinical trials on NIBS for fine motor performance in stroke patients and healthy participants. We computed Hedges’ g for active and sham groups, pooled data as random‐effects models and performed sensitivity analysis on chronicity, montage, frequency of stimulation and risk of bias. Twenty‐nine studies (351 patients and 152 healthy subjects) were reviewed. Effect sizes in stroke populations for transcranial direct current stimulation and repeated transcranial magnetic stimulation were 0.31 [95% confidence interval (CI), 0.08–0.55; P = 0.010; Tau², 0.09; I², 34%; Q, 18.23; P = 0.110] and 0.46 (95% CI, 0.00–0.92; P = 0.05; Tau², 0.38; I², 67%; Q, 30.45; P = 0.007). The effect size of non‐dominant healthy hemisphere transcranial direct current stimulation on non‐dominant hand function was 1.25 (95% CI, 0.09–2.41; P = 0.04; Tau², 1.26; I², 93%; Q, 40.27; P < 0.001). Our results show that NIBS is associated with gains in fine motor performance in chronic stroke patients and healthy subjects. This supports the effects of NIBS on motor learning and encourages investigation to optimize their effects in clinical and research settings.     

Age at onset and the outcomes of schizophrenia: A systematic review and meta‐analysis

The aim of this study was to analyse the effect of age at onset on the long‐term clinical, social and global outcomes of schizophrenia through a systematic review and a meta‐analysis. Original studies were searched from Web of Science, PsycINFO, Pubmed and Scopus, as well as manually. Naturalistic studies with at least a 2‐year follow‐up were included. Of the 3509 search results, 81 articles fulfilled the inclusion criteria. The meta‐analysis was performed in Stata as a random‐effect analysis with correlation coefficients between age at onset and the outcomes (categorized into remission, relapse, hospitalization, positive symptoms, negative symptoms, total symptoms, general clinical outcome, employment, social/occupational functioning and global outcome). There was a statistically significant (P < .05) correlation between younger age at onset and more hospitalizations (number of studies, n = 9; correlation, r = 0.17; 95% confidence interval, CI 0.09–0.25), more negative symptoms (n = 7; r = 0.14; 95% CI 0.01–0.27), more relapses (n = 3; r = 0.11; 95% CI 0.02–0.20), poorer social/occupational functioning (n = 12; r = 0.15; 95% CI 0.05–0.25) and poorer global outcome (n = 13; r = 0.14; 95% CI 0.07–0.22). Other relationships were not significant. This was the first systematic review of the effects of age at onset on the long‐term outcomes of schizophrenia. The results show that age at onset has a small, but significant impact on some of the outcomes of schizophrenia.     

Does the treatment of spastic equinovarus deformity following stroke with botulinum toxin increase gait velocity? A systematic review and meta‐analysis

While botulinum toxin‐A (BT‐A) has been used to treat lower‐limb focal spasticity successfully, its effect on characteristics of gait has not been well defined. The objective of this systematic review was to establish the treatment effect associated with the use of BT‐A for equinovarus to improve gait velocity following stroke, using a meta‐analytic technique. Relevant studies were identified through a literature search encompassing the years 1985 to November 2009. Studies were included if (i) the sample was composed of adult subjects recovering from either first or subsequent stroke, presenting with spastic equinovarus deformity of the ankle preventing full active dorsiflexion, and (ii) subjects who received BT‐A were compared with subjects who had received a placebo, or (iii) in the absence of a placebo‐controlled condition, subject had received BT‐A and was assessed before and after treatment. A standardized mean difference (SMD) ± standard error and 95% confidence interval (CI) for gait velocity between the treatment and control group was calculated for each study, using Hedges’s g, and the results pooled. Eight trials, five randomized controlled trials, and three single group intervention studies were included. Data representing 228 subjects were available for pooled analysis. Treatment with BT‐A was associated with a small improvement in gait velocity (Hedge’s g = 0.193 ± 0.081; 95% CI: 0.033 to 0.353, P < 0.018) representing an increase of 0.044 meters/s. The use of BT‐A for lower‐limb post‐stroke equinovarus because of spasticity was associated with a small, but statistically significant increase in gait velocity.