human
***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: CONTEXT The Systolic Hypertension in the Elderly Program ( SHEP ) demonstrated that treating isolated systolic hypertension in older patients decreased incidence of total stroke , but whether all types of stroke were reduced was not evaluated . OBJECTIVE To investigate antihypertensive drug treatment effects on incidence of stroke by type and subtype , timing of strokes , case-fatality rates , stroke residual effects , and relationship of attained systolic blood pressure to stroke incidence . DESIGN The SHEP study , a r and omized , double-blind , placebo-controlled trial began March 1 , 1985 , and had an average follow-up of 4.5 years . SETTING AND PARTICIPANTS A total of 4736 men and women aged 60 years or older with isolated systolic hypertension at 16 clinical centers in the United States . INTERVENTIONS Patients were r and omly assigned to receive treatment with 12.5 mg/d of chlorthalidone ( step 1 ) ; either 25 mg/d of atenolol or 0.05 mg/d of reserpine ( step 2 ) could be added ( n = 2365 ) ; or placebo ( n = 2371 ) . MAIN OUTCOME MEASURES Occurrence , type and subtype , and timing of first strokes and stroke fatalities ; and change in stroke incidence for participants ( whether in active treatment or placebo groups ) reaching study -specific systolic blood pressure goal ( decrease of at least 20 mm Hg from baseline to below 160 mm Hg ) compared with participants not reaching goal . RESULTS A total of 85 and 132 participants in the active treatment and placebo groups , respectively , had ischemic strokes ( adjusted relative risk [ RR ] , 0.63 ; 95 % confidence interval [ CI ] , 0.48 - 0.82 ) ; 9 and 19 had hemorrhagic strokes ( adjusted RR , 0.46 ; 95 % CI , 0.21 - 1.02 ) ; and 9 and 8 had strokes of unknown type ( adjusted RR , 1.05 ; 95 % CI , 0.40 - 2 . 73 ) , respectively . Four subtypes of ischemic stroke were observed in active treatment and placebo group participants , respectively , as follows : for lacunar , n = 23 and n = 43 ( adjusted RR , 0.53 ; 95 % CI , 0.32 - 0.88 ) ; for embolic , n = 9 and n = 16 ( adjusted RR , 0.56 ; 95 % CI , 0.25 - 1.27 ) ; for atherosclerotic , n = 13 and n = 13 ( adjusted RR , 0 . 99 ; 95 % CI , 0.46 - 2.15 ) ; and for unknown subtype , n = 40 and n = 60 ( adjusted RR , 0.64 ; 95 % CI , 0.43 - 0.96 ) . Treatment effect was observed within 1 year for hemorrhagic strokes but was not seen until the second year for ischemic strokes . Stroke incidence significantly decreased in participants attaining study -specific systolic blood pressure goals . CONCLUSIONS In this study , antihypertensive drug treatment reduced the incidence of both hemorrhagic and ischemic ( including lacunar ) strokes . Reduction in stroke incidence occurred when specific systolic blood pressure goals were attained . JAMA . 2000;284:465 - The Systolic Hypertension in the Elderly Program ( SHEP ) , a r and omized , double-masked , placebo-controlled trial of 4736 persons , was design ed to assess the efficacy of antihypertensive drug treatment to reduce the risk of fatal and nonfatal strokes among people age 60 and over with isolated systolic hypertension . The statistical method used in interim monitoring of results was conditional power ( or stochastic curtailment ) . The findings did not become conclusive until near the completion of the trial , and therefore SHEP was continued to its scheduled closing date . The trial demonstrated a 36 % reduction in the incidence of stroke in the active treatment group ( P = .0003 ) . In addition to evaluating overall efficacy of treatment , the monitoring process considered such other issues as nonstroke outcomes , lag time between first report of stroke and final confirmation of stroke diagnosis , consistency of results across subgroups , and completeness of follow-up . The purpose of this article is to review these factors with primary emphasis on the statistical aspects BACKGROUND There are scant data on the effect of body mass index ( BMI ) ( calculated as weight in kilograms divided by the square of height in meters ) on cardiovascular events and death in older patients with hypertension . OBJECTIVE To determine if low body mass in older patients with hypertension confers an increased risk of death or stroke . PATIENTS Participants were 3975 men and women ( mean age , 71 years ) enrolled in 17 US centers in the Systolic Hypertension in the Elderly Program trial , a r and omized , double-blind , placebo-controlled clinical trial of lowdose antihypertensive therapy  , with follow-up for 5 years . MAIN OUTCOME MEASURES Five-year adjusted mortality and stroke rates from Cox proportional hazards analyses . RESULTS There was no statistically significant relation of death or stroke with BMI in the placebo group ( P = .47 ) , and there was a U- or J-shaped relation in the treatment group . The J-shaped relation of death with BMI in the treated group ( P = .03 ) showed that the lowest probability of death for men was associated with a BMI of 26.0 and for women with a BMI of 29.6 ; the curve was quite flat for women across a wide range of BMI s. For stroke , men and women did not differ , and the BMI nadir for both sexes combined was 29 , with risk increasing steeply at BMI s below 24 . Those in active treatment , however , had lower death and stroke rates compared with those taking placebo . CONCLUSIONS Among older patients with hypertension , a wide range of BMI s was associated with a similar risk of death and stroke ; a low BMI was associated with increased risk . Lean , older patients with hypertension in treatment should be monitored carefully for additional risk factors OBJECTIVE To assess variability in the use of coronary artery bypass grafting ( CABG ) and percutaneous transluminal angioplasty ( PTCA ) in the Systolic Hypertension in the Elderly Program ( SHEP ) cohort with incident coronary heart disease ( CHD ) by age , sex , and race . DESIGN Retrospective analysis of a multicenter prospect i ve cohort study . SETTING Community-based ambulatory population in academic centers . PATIENTS Among 4736 subjects initially enrolled in SHEP , there were 432 incident cases of CHD , excluding those patients who experienced rapid or sudden cardiac death . MAIN OUTCOME MEASURE Incident cases of CHD who underwent CABG or PTCA .  RESULTS Of those participants > or = 60 and < 75 years of age , 7.3 % underwent PTCA , compared with 3.9 % of those > or = 75 years ( P = 0.14 ) . 15.4 % of those < 75 underwent CABG surgery  , compared with 7.8 % of those 75 and older ( P = 0.018 ) . When both of these endpoints , CABG and PTCA , were combined , 22.4 % of those < 75 underwent a procedure , while only 11.7 % of the older cohort did ( P = 0.005 ) . Twenty-six percent of men underwent either CABG or PTCA , while only 9.1 % of women did ( P < 0.001 ) . Of those < 75 years of age , 31.1 % of men and 12.3 % of women underwent CABG or PTCA ( P < 0.001 ) . In the 75 and older age category , 19.5 % of men underwent these interventions , compared with 5.9 % of women ( P = 0.005 ) . Active treatment group was significantly associated with decreased use of procedures in participants < 75 year old with CHD . Race , activity limitations , number of comorbid conditions , education level , marital status , employment status , and social support were not significantly associated with CABG or PTCA use . When the variables studied were entered into a logistic regression model , increased age and female sex remained independently associated with decreased  CABG and PTCA use . CONCLUSION In the SHEP trial older patients and women , regardless of comorbid conditions , socioeconomic status , and social support , underwent less intensive cardiovascular interventions than did younger patients and men when they developed CHD BACKGROUND Blood pressure reduction achieved with beta-blockers and diuretics is the best recorded intervention to date for prevention of cardiovascular morbidity and death in patients with hypertension . Left ventricular hypertrophy ( LVH ) is a strong independent indicator of risk of cardiovascular morbidity and death . We aim ed to establish whether selective blocking of angiotensin II improves LVH beyond reducing blood pressure and , consequently , reduces cardiovascular morbidity and death . METHODS We did a double-masked , r and omised , parallel-group trial in 9193 participants aged 55 - 80 years with essential hypertension ( sitting blood pressure 160 - 200/95 - 115 mm Hg ) and LVH ascertained by electrocardiography ( ECG ) . We assigned participants once daily losartan-based or atenolol-based antihypertensive treatment for at least 4 years and until 1040 patients had a primary cardiovascular event ( death , myocardial infa rct ion , or stroke ) . We used Cox regression analysis to compare regimens . FINDINGS Blood pressure fell by 30.2/16.6 ( SD 18.5/10.1 ) and 29.1/16.8 mm Hg ( 19.2/10.1 ) in the losartan and atenolol groups , respectively . The primary composite endpoint occurred in 508 losartan ( 23.8 per 1000 patient-years ) and 588 atenolol patients ( 27.9 per 1000 patient-years ; relative risk 0.87 , 95 % CI 0.77 - 0.98 , p=0.021 ) . 204 losartan and 234 atenolol patients died from cardiovascular disease ( 0.89 , 0.73 - 1.07 , p=0.206 ) ; 232 and 309 , respectively , had fatal or non-fatal stroke ( 0.75 , 0.63 - 0.89 , p=0.001 ) ; and myocardial infa rct ion ( non-fatal and fatal ) occurred in 198 and 188 , respectively ( 1.07 , 0.88 - 1.31 , p=0.491 ) . New-onset diabetes was less frequent with losartan . Interpretation Losartan prevents more cardiovascular morbidity and death than atenolol for a similar reduction in blood pressure and is better tolerated . Losartan seems to confer benefits beyond reduction in blood pressure The Oslo Hypertension Study began in 1972 ; patients were followed for an average of 66 months ( range : 60 to 78 ) . A total of 785 healthy men , aged 40 to 49 , with mild hypertension was r and omly assigned to either a drug-treated group or to an untreated control group . Hydrochlorothiazide was used alone in 36 percent of patients , in combination with propranolol in 26 percent , and with methyldopa in 20 percent . Other drugs , including combinations with hydrochlorothiazide , were used in 18 percent . A total of 95 percent of patients in the drug-treated group received hydrochlorothiazide .  Complications of hypertension such as stroke and aneurysm occurred only in the control group . Coronary events were more numerous in the drug-treated group ; thus , the total incidence of cardiovascular complications did not significantly differ between the treated and untreated groups . After five and 10 years , total mortality was the same in both groups . However , the coronary heart disease mortality rate at 10 years was significantly greater in the drug-treated group than in the untreated control group ( 14 versus three , p less than 0.01 ) . This article presents possible reasons for the failure of antihypertensive drug therapy to prevent coronary heart disease . The adverse effect of diuretics and beta-adrenergic blockers , both on lipid and carbohydrate metabolism , is contrasted with the effect of the alpha-adrenergic blocker prazosin , which has been shown to have no adverse effect on the blood lipid profile . In a short-term trial that was part of the Oslo Study , prazosin was found to reduce total serum cholesterol by 9 percent , low-density lipoprotein and very-low-density lipoprotein cholesterol by 10 percent , and total triglycerides by 16 percent . All these changes are statistically significant The Systolic Hypertension in the Elderly Program ( SHEP ) is a r and omized double-blind placebo-controlled trial to determine if antihypertensive treatment of isolated systolic hypertension ( ISH ) [ systolic blood pressure ( SBP ) greater than or equal to 160 mmHg , diastolic blood pressure ( DBP ) less than 90 mmHg ] reduces the 5 year incidence of fatal and nonfatal stroke . 
    Output:
    
agent
Antihypertensive drugs used in the treatment of adults ( primary prevention ) with mild hypertension ( systolic BP 140 - 159 mmHg and /or diastolic BP 90 - 99 mmHg ) have not been shown to reduce mortality or morbidity in RCTs .
More RCTs are needed in this prevalent population to know whether the benefits of treatment exceed the harms
***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: CONTEXT The Systolic Hypertension in the Elderly Program ( SHEP ) demonstrated that treating isolated systolic hypertension in older patients decreased incidence of total stroke , but whether all types of stroke were reduced was not evaluated . OBJECTIVE To investigate antihypertensive drug treatment effects on incidence of stroke by type and subtype , timing of strokes , case-fatality rates , stroke residual effects , and relationship of attained systolic blood pressure to stroke incidence . DESIGN The SHEP study , a r and omized , double-blind , placebo-controlled trial began March 1 , 1985 , and had an average follow-up of 4.5 years . SETTING AND PARTICIPANTS A total of 4736 men and women aged 60 years or older with isolated systolic hypertension at 16 clinical centers in the United States . INTERVENTIONS Patients were r and omly assigned to receive treatment with 12.5 mg/d of chlorthalidone ( step 1 ) ; either 25 mg/d of atenolol or 0.05 mg/d of reserpine ( step 2 ) could be added ( n = 2365 ) ; or placebo ( n = 2371 ) . MAIN OUTCOME MEASURES Occurrence , type and subtype , and timing of first strokes and stroke fatalities ; and change in stroke incidence for participants ( whether in active treatment or placebo groups ) reaching study -specific systolic blood pressure goal ( decrease of at least 20 mm Hg from baseline to below 160 mm Hg ) compared with participants not reaching goal . RESULTS A total of 85 and 132 participants in the active treatment and placebo groups , respectively , had ischemic strokes ( adjusted relative risk [ RR ] , 0.63 ; 95 % confidence interval [ CI ] , 0.48 - 0.82 ) ; 9 and 19 had hemorrhagic strokes ( adjusted RR , 0.46 ; 95 % CI , 0.21 - 1.02 ) ; and 9 and 8 had strokes of unknown type ( adjusted RR , 1.05 ; 95 % CI , 0.40 - 2 . 73 ) , respectively . Four subtypes of ischemic stroke were observed in active treatment and placebo group participants , respectively , as follows : for lacunar , n = 23 and n = 43 ( adjusted RR , 0.53 ; 95 % CI , 0.32 - 0.88 ) ; for embolic , n = 9 and n = 16 ( adjusted RR , 0.56 ; 95 % CI , 0.25 - 1.27 ) ; for atherosclerotic , n = 13 and n = 13 ( adjusted RR , 0 . 99 ; 95 % CI , 0.46 - 2.15 ) ; and for unknown subtype , n = 40 and n = 60 ( adjusted RR , 0.64 ; 95 % CI , 0.43 - 0.96 ) . Treatment effect was observed within 1 year for hemorrhagic strokes but was not seen until the second year for ischemic strokes . Stroke incidence significantly decreased in participants attaining study -specific systolic blood pressure goals . CONCLUSIONS In this study , antihypertensive drug treatment reduced the incidence of both hemorrhagic and ischemic ( including lacunar ) strokes . Reduction in stroke incidence occurred when specific systolic blood pressure goals were attained . JAMA . 2000;284:465 - The Systolic Hypertension in the Elderly Program ( SHEP ) , a r and omized , double-masked , placebo-controlled trial of 4736 persons , was design ed to assess the efficacy of antihypertensive drug treatment to reduce the risk of fatal and nonfatal strokes among people age 60 and over with isolated systolic hypertension . The statistical method used in interim monitoring of results was conditional power ( or stochastic curtailment ) . The findings did not become conclusive until near the completion of the trial , and therefore SHEP was continued to its scheduled closing date . The trial demonstrated a 36 % reduction in the incidence of stroke in the active treatment group ( P = .0003 ) . In addition to evaluating overall efficacy of treatment , the monitoring process considered such other issues as nonstroke outcomes , lag time between first report of stroke and final confirmation of stroke diagnosis , consistency of results across subgroups , and completeness of follow-up . The purpose of this article is to review these factors with primary emphasis on the statistical aspects BACKGROUND There are scant data on the effect of body mass index ( BMI ) ( calculated as weight in kilograms divided by the square of height in meters ) on cardiovascular events and death in older patients with hypertension . OBJECTIVE To determine if low body mass in older patients with hypertension confers an increased risk of death or stroke . PATIENTS Participants were 3975 men and women ( mean age , 71 years ) enrolled in 17 US centers in the Systolic Hypertension in the Elderly Program trial , a r and omized , double-blind , placebo-controlled clinical trial of lowdose antihypertensive therapy  , with follow-up for 5 years . MAIN OUTCOME MEASURES Five-year adjusted mortality and stroke rates from Cox proportional hazards analyses . RESULTS There was no statistically significant relation of death or stroke with BMI in the placebo group ( P = .47 ) , and there was a U- or J-shaped relation in the treatment group . The J-shaped relation of death with BMI in the treated group ( P = .03 ) showed that the lowest probability of death for men was associated with a BMI of 26.0 and for women with a BMI of 29.6 ; the curve was quite flat for women across a wide range of BMI s. For stroke , men and women did not differ , and the BMI nadir for both sexes combined was 29 , with risk increasing steeply at BMI s below 24 . Those in active treatment , however , had lower death and stroke rates compared with those taking placebo . CONCLUSIONS Among older patients with hypertension , a wide range of BMI s was associated with a similar risk of death and stroke ; a low BMI was associated with increased risk . Lean , older patients with hypertension in treatment should be monitored carefully for additional risk factors OBJECTIVE To assess variability in the use of coronary artery bypass grafting ( CABG ) and percutaneous transluminal angioplasty ( PTCA ) in the Systolic Hypertension in the Elderly Program ( SHEP ) cohort with incident coronary heart disease ( CHD ) by age , sex , and race . DESIGN Retrospective analysis of a multicenter prospect i ve cohort study . SETTING Community-based ambulatory population in academic centers . PATIENTS Among 4736 subjects initially enrolled in SHEP , there were 432 incident cases of CHD , excluding those patients who experienced rapid or sudden cardiac death . MAIN OUTCOME MEASURE Incident cases of CHD who underwent CABG or PTCA .  RESULTS Of those participants > or = 60 and < 75 years of age , 7.3 % underwent PTCA , compared with 3.9 % of those > or = 75 years ( P = 0.14 ) . 15.4 % of those < 75 underwent CABG surgery  , compared with 7.8 % of those 75 and older ( P = 0.018 ) . When both of these endpoints , CABG and PTCA , were combined , 22.4 % of those < 75 underwent a procedure , while only 11.7 % of the older cohort did ( P = 0.005 ) . Twenty-six percent of men underwent either CABG or PTCA , while only 9.1 % of women did ( P < 0.001 ) . Of those < 75 years of age , 31.1 % of men and 12.3 % of women underwent CABG or PTCA ( P < 0.001 ) . In the 75 and older age category , 19.5 % of men underwent these interventions , compared with 5.9 % of women ( P = 0.005 ) . Active treatment group was significantly associated with decreased use of procedures in participants < 75 year old with CHD . Race , activity limitations , number of comorbid conditions , education level , marital status , employment status , and social support were not significantly associated with CABG or PTCA use . When the variables studied were entered into a logistic regression model , increased age and female sex remained independently associated with decreased  CABG and PTCA use . CONCLUSION In the SHEP trial older patients and women , regardless of comorbid conditions , socioeconomic status , and social support , underwent less intensive cardiovascular interventions than did younger patients and men when they developed CHD BACKGROUND Blood pressure reduction achieved with beta-blockers and diuretics is the best recorded intervention to date for prevention of cardiovascular morbidity and death in patients with hypertension . Left ventricular hypertrophy ( LVH ) is a strong independent indicator of risk of cardiovascular morbidity and death . We aim ed to establish whether selective blocking of angiotensin II improves LVH beyond reducing blood pressure and , consequently , reduces cardiovascular morbidity and death . METHODS We did a double-masked , r and omised , parallel-group trial in 9193 participants aged 55 - 80 years with essential hypertension ( sitting blood pressure 160 - 200/95 - 115 mm Hg ) and LVH ascertained by electrocardiography ( ECG ) . We assigned participants once daily losartan-based or atenolol-based antihypertensive treatment for at least 4 years and until 1040 patients had a primary cardiovascular event ( death , myocardial infa rct ion , or stroke ) . We used Cox regression analysis to compare regimens . FINDINGS Blood pressure fell by 30.2/16.6 ( SD 18.5/10.1 ) and 29.1/16.8 mm Hg ( 19.2/10.1 ) in the losartan and atenolol groups , respectively . The primary composite endpoint occurred in 508 losartan ( 23.8 per 1000 patient-years ) and 588 atenolol patients ( 27.9 per 1000 patient-years ; relative risk 0.87 , 95 % CI 0.77 - 0.98 , p=0.021 ) . 204 losartan and 234 atenolol patients died from cardiovascular disease ( 0.89 , 0.73 - 1.07 , p=0.206 ) ; 232 and 309 , respectively , had fatal or non-fatal stroke ( 0.75 , 0.63 - 0.89 , p=0.001 ) ; and myocardial infa rct ion ( non-fatal and fatal ) occurred in 198 and 188 , respectively ( 1.07 , 0.88 - 1.31 , p=0.491 ) . New-onset diabetes was less frequent with losartan . Interpretation Losartan prevents more cardiovascular morbidity and death than atenolol for a similar reduction in blood pressure and is better tolerated . Losartan seems to confer benefits beyond reduction in blood pressure The Oslo Hypertension Study began in 1972 ; patients were followed for an average of 66 months ( range : 60 to 78 ) . A total of 785 healthy men , aged 40 to 49 , with mild hypertension was r and omly assigned to either a drug-treated group or to an untreated control group . Hydrochlorothiazide was used alone in 36 percent of patients , in combination with propranolol in 26 percent , and with methyldopa in 20 percent . Other drugs , including combinations with hydrochlorothiazide , were used in 18 percent . A total of 95 percent of patients in the drug-treated group received hydrochlorothiazide .  Complications of hypertension such as stroke and aneurysm occurred only in the control group . Coronary events were more numerous in the drug-treated group ; thus , the total incidence of cardiovascular complications did not significantly differ between the treated and untreated groups . After five and 10 years , total mortality was the same in both groups . However , the coronary heart disease mortality rate at 10 years was significantly greater in the drug-treated group than in the untreated control group ( 14 versus three , p less than 0.01 ) . This article presents possible reasons for the failure of antihypertensive drug therapy to prevent coronary heart disease . The adverse effect of diuretics and beta-adrenergic blockers , both on lipid and carbohydrate metabolism , is contrasted with the effect of the alpha-adrenergic blocker prazosin , which has been shown to have no adverse effect on the blood lipid profile . In a short-term trial that was part of the Oslo Study , prazosin was found to reduce total serum cholesterol by 9 percent , low-density lipoprotein and very-low-density lipoprotein cholesterol by 10 percent , and total triglycerides by 16 percent . All these changes are statistically significant The Systolic Hypertension in the Elderly Program ( SHEP ) is a r and omized double-blind placebo-controlled trial to determine if antihypertensive treatment of isolated systolic hypertension ( ISH ) [ systolic blood pressure ( SBP ) greater than or equal to 160 mmHg , diastolic blood pressure ( DBP ) less than 90 mmHg ] reduces the 5 year incidence of fatal and nonfatal stroke . 
    Output:
    