***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background and Purpose — Among patients with acute stroke , high blood pressure is often associated with poor outcome , although the reason is unclear . We analyzed data from the International Stroke Trial ( IST ) to explore the relationship between  systolic blood pressure ( SBP ) , subsequent clinical events over the next 2 weeks , and functional outcome at 6 months in patients with acute stroke . Methods — We included in the analysis 17 398 patients from IST with confirmed ischemic stroke . A single measurement of SBP was made immediately before r and omization . Clinical events within 14 days of r and omization were recorded : recurrent ischemic stroke , symptomatic intracranial hemorrhage , death result ing from presumed cerebral edema , fatal coronary heart disease , and death . Survival and dependency were assessed at 6 months . Outcomes were adjusted for age , sex , clinical stroke syndrome , time to r and omization , consciousness level , atrial fibrillation , and treatment allocation ( aspirin , unfractionated heparin , both , or neither ) . Results — A U-shaped relationship was found between baseline SBP and both early death and late death or dependency : early death increased by 17.9 % for every 10 mm Hg below 150 mm Hg ( P < 0.0001 ) and by 3.8 % for every 10 mm Hg above 150 mm Hg ( P = 0.016 ) . The rate of recurrent ischemic stroke within 14 days increased by 4.2 % for every 10–mm Hg increase in SBP ( P = 0.023 ) ; this association was present in both fatal and nonfatal recurrence . Death result ing from presumed cerebral edema was independently associated with high SBP ( P = 0.004 ) . No relationship between symptomatic intracranial hemorrhage and SBP was seen . Low SBP was associated with a severe clinical stroke ( total anterior circulation syndrome ) and an excess of deaths from coronary heart disease ( P = 0.002 ) . Conclusions — Both high blood pressure and low blood pressure were independent prognostic factors for poor outcome , relationships that appear to be mediated in part by increased rates of early recurrence and death result ing from presumed cerebral edema in patients with high blood pressure and increased coronary heart disease events in those with low blood pressure . The occurrence of symptomatic intracranial hemorrhage within 14 days was independent of SBP Background and Purpose — The practicalities of doing ambulance-based trials where paramedics perform all aspects of a clinical trial involving patients with ultra-acute stroke have not been assessed . Methods — We performed a r and omized controlled trial with screening , consent , r and omization , and treatment performed by paramedics prior to hospitalization . Patients with probable ultra-acute stroke ( < 4 hours ) and systolic blood pressure ( SBP ) > 140 mm Hg were r and omized to transdermal glyceryl trinitrate ( GTN ; 5 mg/24 hours ) or none ( blinding under gauze dressing ) for 7 days with the first dose given by paramedics . The primary outcome was SBP at 2 hours . Results — Of a planned 80 patients , 41 ( 25 GTN , 16 no GTN ) were enrolled > 22 months with median age [ interquartile range ] 79 [ 16 ] years ; men 22 ( 54 % ) ; SBP 168 [ 46 ] ; final diagnosis : stroke 33 ( 80 % ) and transient ischemic attack 3 ( 7 % ) .  Time to r and omization was 55 [ 75 ] minutes . After treatment with GTN versus no GTN , SBP at 2 hours was 153 [ 31 ] versus 174 [ 27 ] mm Hg , respectively , with difference −18 [ 30 ] mm Hg ( P=0.030 ) . GTN improved functional outcome with a shift in the modified Rankin Scale by 1 [ 3 ] point ( P=0.040 ) . The rates of death , 4 ( 16 % ) versus 6 ( 38 % ; P=0.15 ) , and serious adverse events , 14 ( 56 % ) versus 10 ( 63 % ; P=0.75 ) , did not differ between GTN and no GTN . Conclusions — Paramedics can successfully enroll patients with ultra-acute stroke into an ambulance-based trial . GTN  reduces SBP at 2 hours and seems to be safe in ultra-acute stroke . A larger trial is needed to assess whether GTN improves functional outcome . Clinical Trial Registration — URL : http://www.controlled-trials.com/IS RCT N66434824/66434824 . Unique identifier : 66434824 Summary Background High blood pressure is associated with poor outcome after stroke . Whether blood pressure should be lowered early after stroke , and whether to continue or temporarily withdraw existing antihypertensive drugs , is not known . We assessed outcomes after stroke in patients given drugs to lower their blood pressure . Methods In our multicentre , partial-factorial trial , we r and omly assigned patients admitted to hospital with an acute ischaemic or haemorrhagic stroke and raised systolic blood pressure ( systolic 140–220 mm Hg ) to 7 days of transdermal glyceryl trinitrate ( 5 mg per day ) , started within 48 h of stroke onset , or to  no glyceryl trinitrate ( control group ) . A subset of patients who were taking antihypertensive drugs before their stroke were also r and omly assigned to continue or stop taking these drugs . The primary outcome was function , assessed with the modified Rankin Scale at 90 days by observers masked to treatment assignment . This study is registered , number IS RCT N99414122 . Findings Between July 20 , 2001 , and Oct 14 , 2013 , we enrolled 4011 patients .  Mean blood pressure was 167 ( SD 19 ) mm Hg/90 ( 13 ) mm Hg at baseline ( median 26 h [ 16–37 ] after stroke onset ) , and was significantly reduced on day 1 in 2000 patients allocated to glyceryl trinitrate compared with 2011 controls ( difference −7·0 [ 95 % CI −8·5 to −5·6 ] mm Hg/–3·5 [ –4·4 to −2·6 ] mm Hg ; both p<0·0001 ) , and on day 7 in 1053 patients allocated to continue antihypertensive drugs compared with 1044 patients r and omised to stop them ( difference −9·5 [ 95 % CI −11·8 to −7·2 ] mm Hg/–5·0 [ –6·4 to −3·7 ] mm Hg ; both p<0·0001 ) . Functional outcome at day 90 did not differ in either treatment comparison — the adjusted common odds ratio ( OR ) for worse outcome with glyceryl trinitrate versus no glyceryl trinitrate was 1·01 ( 95 % CI 0·91–1·13 ; p=0·83 ) , and with continue versus stop antihypertensive drugs OR was 1·05 ( 0·90–1·22 ; p=0·55 ) . Interpretation In patients with acute stroke and high blood pressure , transdermal glyceryl trinitrate lowered blood pressure and had acceptable safety but did not improve functional outcome . We show no evidence to support continuing prestroke antihypertensive drugs in patients in the first few days after acute stroke . Funding UK Medical Research Council BACKGROUND Whether rapid lowering of elevated blood pressure would improve the outcome in patients with intracerebral hemorrhage is not known . METHODS We r and omly assigned 2839 patients who had had a spontaneous intracerebral hemorrhage within the previous 6 hours and who had elevated systolic blood pressure to  receive intensive treatment to lower their blood pressure ( with a target systolic level of < 140 mm Hg within 1 hour ) or guideline -recommended treatment ( with a target systolic level of < 180 mm Hg ) with the use of agents of the physician 's choosing . The primary outcome was death or major disability , which was defined as a score of 3 to 6 on the modified Rankin scale ( in which a score of 0 indicates no symptoms , a score of 5 indicates severe disability , and a score of 6 indicates death ) at 90 days . A prespecified ordinal analysis of the modified Rankin score was also performed . The rate of serious adverse events was compared between the two groups . RESULTS Among the 2794 participants for whom the primary outcome could be determined , 719 of 1382 participants ( 52.0 % ) receiving intensive treatment , as compared with 785 of 1412 ( 55.6 % ) receiving guideline -recommended treatment , had a primary outcome event ( odds ratio with intensive treatment , 0.87 ; 95 % confidence interval [ CI ] , 0.75 to 1.01 ; P=0.06 ) . The ordinal analysis showed significantly lower modified Rankin scores with intensive treatment ( odds ratio for greater disability , 0.87 ; 95 % CI , 0.77 to 1.00 ; P=0.04 ) . Mortality was 11.9 % in the group receiving intensive treatment and 12.0 % in the group receiving guideline -recommended treatment . Nonfatal serious adverse events occurred in 23.3 % and 23.6 % of the patients in the two groups , respectively . CONCLUSIONS In patients with intracerebral hemorrhage , intensive lowering of blood pressure did not result in a significant reduction in the rate of the primary outcome of death or severe disability . An ordinal analysis of modified Rankin scores indicated improved functional outcomes with intensive lowering of blood pressure . ( Funded by the National Health and Medical Research Council of Australia ; INTERACT2 Clinical Trials.gov number , NCT00716079 . ) High blood pressure is common during the acute phase of stroke and is associated with a poor outcome . However , the management of high blood pressure remains unclear . The ‘ Efficacy of Nitric Oxide in Stroke ’ trial tested whether transdermal glyceryl trinitrate , a nitric oxide donor that lowers blood pressure , is safe and effective in improving outcome after acute stroke . Efficacy of Nitric Oxide in Stroke is an international multicenter , prospect i ve , r and omized , single-blind , blinded endpoint trial , with funding from the UK Medical Research Council . Patients with acute ischemic stroke or intracerebral hemorrhage and systolic blood pressure 140–220 mmHg were r and omized to glyceryl trinitrate or no glyceryl trinitrate and , where relevant , to continue or stop prestroke antihypertensive therapy . The primary outcome is shift in modified Rankin Scale at three-months . Patients or relatives gave written informed ( proxy ) consent , and all sites had research ethics approval . Analyses will be done by intention to treat . This paper and attachment describe the trial 's statistical analysis plan , developed prior to unblinding of date . The statistical analysis plan contains design and methods for analyses , and unpopulated tables and figures for the two primary publications and some secondary publications . The data base will be locked in late February 2014 in preparation for presentation of the results in May 2014 . The data from the trial will improve the precision of the estimates of the overall treatment effects ( efficacy and safety ) of results from completed trials of blood pressure management in acute stroke , and provide the first large-scale r and omized evidence on transdermal glyceryl trinitrate , and of continuing ( vs. stopping ) prestroke antihypertensive medications , in acute stroke RATIONALE The management of perioperative period for patients with spontaneous intracerebral hemorrhage affects the prognosis . Elevated blood pressure is common in the patients with spontaneous intracerebral hemorrhage and related to a poor outcome . However , study on antihypertensive treatment for surgical patients with spontaneous intracerebral hemorrhage is insufficient . AIMS To determine if the intensive antihypertensive treatment improves the prognosis compared with the conservative antihypertensive treatment followed guidelines in perioperative period for patients with spontaneous intracerebral hemorrhage . DESIGN PATICH is a prospect i ve , parallel , r and omized , assessor-blinded trial . Two hundred eligible patients will be assigned to the intensive group and conservative group r and omly . Patients allocated to the intensive group will receive an intensive antihypertensive treatment aim ing to achieve a target systolic blood pressure of between 120 mmHg and 140 mmHg while the patients in the conservative group will receive conservative antihypertensive treatment as recommended by guidelines for 7 days . Operation will be conducted by well-trained surgeons and the best medical treatment will be given in all patients . Patients will be followed up at 7 days , 30 days , and 90 days . STUDY OUTCOMES Primary outcome of this study is the rate of rehemorrhage in 7 days after surgery . Secondary outcomes include death and dependency at 90 days incidence of ischemic stroke , separate rate of death and dependency at 90 days , health related quality of life ( HRQoL ) at 90 days , incidence of other vascular events , and days of hospitalization . Dependency is defined by a score of 3 - 5 based on the modified Rankin Scale ( mRS ) High blood pressure in acute stroke is common and appears to be associated with a poor outcome . Lowering blood pressure might therefore improve outcome , provided that cerebral perfusion is not compromised . We assessed the effects of glyceryl trinitrate ( GTN ) on cerebral and systemic hemodynamic measures in acute stroke . Ninety patients with acute ischemic or hemorrhagic stroke were r and omized within  
    Output:
    
In people with acute stroke , GTN reduces blood pressure , increases heart rate and headache , but does not alter clinical outcome ( all based on high- quality evidence )