***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 
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    Input: Objectives To evaluate salt sensitivity in elderly subjects with different forms of hypertension and controls and to investigate any modulation by genotype Design R and omized , double-blinded , placebo-controlled latin-square Setting Tertiary referral hospital Participants Community subjects ( n = 46 ) aged ⩾ 60 years classified as isolated systolic hypertension [ ISH ; systolic blood pressure ( SBP ) ⩾ 160 , diastolic blood pressure ( DBP ) < 90 mmHg , n = 19 ] , diastolic ± systolic hypertension ( SDH ; DBP ⩾ 90 mmHg , n = 10 ) and normotension ( SBP < 160 , DBP < 90 mmHg , n = 17 ) .  Intervention Four 14 day treatments , 50 , 100 , 200 and 300 mmol/day of sodium chloride supplementation interspersed with 14 day washout periods on a salt-restricted diet . Main outcome measures The 24 h blood pressure , heart rate , weight , urinary sodium and creatinine clearance measured during baseline , treatment and washout periods and angiotensinogen ( AGT ) and angiotensin converting enzyme ( ACE ) genotypes . Results For the entire cohort , the mean ± st and ard error ( SE ) of change from baseline in SBP for 50 , 100 , 200 and 300 mmol/day salt was 7.7 ± 2.4 , 12.1 ± 2.4 , 16.6 ± 3.0 , 18.5 ± 2.6 mmHg , respectively . For DBP , the respective changes were:− 0.1 ± 1.5 , 2.4 ± 1.6 , 3.0 ± 1.5 , 5.8 ± 1.7 mmHg . The increase in SBP among ISH subjects was significantly higher than among subjects in the SDH and normotensive groups ( P < 0.05 ) . AGT genotype influenced the effect of salt dose on the change in DBP ( P = 0.006 ) but not SBP ( P = 0.7 ) . Conclusions In healthy , older subjects , a linear increase in BP occurred with increasing salt dose , it appeared most pronounced in ISH subjects and could be modulated by AGT genotype The aim of the present study was to evaluate the effects of a normal-sodium ( 120 mmol sodium ) diet compared with a low-sodium diet ( 80 mmol sodium ) on readmissions for CHF ( congestive heart failure ) during 180 days of follow-up in compensated patients with CHF . A total of 232 compensated CHF patients ( 88 female and 144 male ; New York Heart Association class II-IV ; 55 - 83 years of age , ejection fraction < 35 % and serum creatinine < 2 mg/dl ) were r and omized into two groups : group 1 contained 118 patients ( 45 females and 73 males ) receiving a normal-sodium diet plus oral furosemide [ 250 - 500 mg , b.i.d . ( twice a day ) ] ; and group 2 contained 114 patients ( 43 females and 71 males ) receiving a low-sodium diet plus oral furosemide ( 250 - 500 mg , b.i.d . ) . The treatment was given at 30 days after discharge and for 180 days , in association with a fluid intake of 1000 ml per day . Signs of CHF , body weight , blood pressure , heart rate , laboratory parameters , ECG , echocardiogram , levels of BNP ( brain natriuretic peptide ) and aldosterone levels , and PRA ( plasma renin activity ) were examined at baseline ( 30 days after discharge ) and after 180 days . The normal-sodium group had a significant reduction ( P<0.05 ) in readmissions . BNP values were lower in the normal-sodium group compared with the low sodium group ( 685+/-255 compared with 425+/-125 pg/ml respectively ; P<0.0001 ) . Significant ( P<0.0001 ) increases in aldosterone and PRA were observed in the low-sodium group during follow-up , whereas the normal-sodium group had a small significant reduction ( P=0.039 ) in aldosterone levels and no significant difference in PRA . After 180 days of follow-up , aldosterone levels and PRA were significantly ( P<0.0001 ) higher in the low-sodium group . The normal-sodium group had a lower incidence of rehospitalization during follow-up and a significant decrease in plasma BNP and aldosterone levels , and PRA . The results of the present study show that a normal-sodium diet improves outcome , and sodium depletion has detrimental renal and neurohormonal effects with worse clinical outcome in compensated CHF patients . Further studies are required to determine if this is due to a high dose of diuretic or the low-sodium diet BACKGROUND Few trials have evaluated the effects of reduced sodium intake in older individuals , and no trial has examined the effects in relevant subgroups such as African Americans . PATIENTS AND METHODS The effects of sodium reduction on blood pressure ( BP ) and hypertension control were evaluated in 681 patients with hypertension , aged 60 to 80 years , r and omly assigned to a reduced sodium intervention or control group .  Participants ( 47 % women , 23 % African Americans ) had systolic BP less than 145 mm Hg and diastolic BP less than 85 mm Hg while taking 1 antihypertensive medication . Three months after the start of intervention , medication was withdrawn . The primary end point was occurrence of an average systolic BP of 150 mm Hg or more , an average diastolic BP of 90 mm Hg or more , the resumption of medication , or a cardiovascular event during follow-up ( mean , 27.8 months ) . RESULTS Compared with control , mean urinary sodium excretion was 40 mmol/d less in the reduced sodium intervention group ( P<.001 ) ; significant reductions in sodium excretion occurred in subgroups defined by sex , race , age , and obesity . Prior to medication withdrawal , mean reductions in systolic and diastolic BPs from the reduced sodium intervention , net of control , were 4.3 mm Hg ( P<.001 ) and 2.0 mm Hg ( P = .001 ) . During follow-up , an end point occurred in 59 % of reduced sodium and 73 % of control group participants ( relative hazard ratio = 0.68 , P<.001 ) . In African Americans , the corresponding relative hazard ratio was 0.56 ( P = .005 ) ; results were similar in other subgroups . In dose-response analyses , end points were progressively less frequent with greater sodium reduction ( P for trend = .002 ) . CONCLUSION A reduced sodium intake is a broadly effective , nonpharmacologic therapy that can lower BP and control hypertension in older individuals This study presents an extensive analysis of the effects on blood pressure ( BP ) of changes in sodium intake over a wide array of subgroups , including joint subgroups defined by age and hypertension status , race or ethnicity and hypertension status , and gender and race or ethnicity . Participants were given 3 levels of sodium ( 50 , 100 , and 150 mmol/2,100 kcal ) for 30 days while consuming the Dietary Approaches to Stop Hypertension ( DASH ) diet ( rich in fruits , vegetables , and low-fat dairy ) or a more typical American diet . Within each diet and subgroup , there was a general pattern such that the lower the sodium level , the greater the mean reduction in BP . Sodium reduction from 100 to 50 mmol/2,100 kcal generally had twice the effect on BP as reduction from 150 to 100 mmol/2,100 kcal . Age had a strong and grade d influence on the effect of sodium within the typical and DASH diets , respectively : -4.8 and -1.0 mm Hg systolic for 23 to 41 years , -5.9 and -1.8 mm Hg for 42 to 47 years , -7.5 and -4.3 mm Hg for 48 to 54 years , and -8.1 and -6.0 mm Hg for 55 to 76 years . The influence of age on the effect of sodium reduction was particularly strong in nonhypertensive patients : -3.7 mm Hg systolic for < 45 years and -7.0 mm Hg for > 45 years with the typical diet and -0.7 and -2.8 mm Hg with the DASH diet . Reduced sodium  intake and the DASH diet should be advocated for the prevention and treatment of high BP , particularly because the benefits to BP strengthen as subjects enter middle age , when the rate of cardiovascular disease increases sharply Computer simulations have been used to estimate the mortality benefits from population -wide reductions in dietary  sodium , although comparisons of these estimates have not been rigorously evaluated . We used 3 different approaches to model the effect of sodium reduction in the US population over the next 10 years , incorporating evidence for direct effects on cardiovascular disease mortality ( method 1 ) , indirect effects mediated by blood pressure changes as observed in r and omized controlled trials of antihypertension medications ( method 2 ) , or epidemiological studies ( method 3).The 3 different modeling approaches were used to model the same scenarios : scenario A , gradual uniform reduction totaling 40 % over 10 years ; scenario B , instantaneous 40 % reduction in sodium consumption sustained for 10 years to achieve a population -wide mean of 2200 mg/d ; and scenario C , instantaneous reduction to 1500 mg sodium per day sustained for 10 years . All 3 methods consistently show a substantial health benefit for reductions in dietary sodium under each of the 3 scenarios tested . A gradual reduction in dietary sodium over the next decade ( scenario A ) as might be achieved with a range of proposed public health interventions would yield considerable health benefits over the next decade , with mean effects across the 3 models ranging from 280 000 to 500 000 deaths averted . Projections of instantaneous reductions illustrate the maximum benefits that could be achieved ( 0.7–1.2 million deaths averted in 10 years ) . Under 3 different modeling assumptions , the projected health benefits from reductions in dietary sodium are substantial BACKGROUND The effect of dietary composition on blood pressure is a subject of public health importance . We studied the effect of different levels of dietary sodium , in conjunction with the Dietary Approaches to Stop Hypertension ( DASH ) diet , which is rich in vegetables , fruits , and low-fat dairy products , in persons with and in those without hypertension . METHODS A total of 412 participants were r and omly assigned to eat either a control diet typical of intake in the United States or the DASH diet . Within the assigned diet , participants ate foods with high , intermediate , and low levels of sodium for 30 consecutive days each , in r and om order . RESULTS Reducing the sodium intake from the high to the intermediate level reduced the systolic blood pressure by 2.1 mm Hg ( P<0.001 ) during the control diet and by 1.3 mm Hg ( P=0.03 ) during the DASH diet . Reducing the sodium intake from the intermediate to the low level caused additional reductions of 4.6 mm Hg during the control diet ( P<0.001 ) and 1.7 mm Hg during the DASH diet ( P<0.01 ) . The effects of sodium were observed in participants with and in those without hypertension , blacks and those of other races , and women and men . The DASH diet was associated with a significantly lower systolic blood pressure at each sodium level ; and the difference was greater with high sodium levels than with low ones . As compared with the control diet with a high sodium level , the DASH diet with a low sodium level led to a mean systolic blood pressure that was 7.1 mm Hg lower in participants without hypertension , and 11.5 mm Hg lower in participants with hypertension . CONCLUSIONS The reduction of sodium intake to levels below the current recommendation of 100 mmol per day and the DASH diet both lower blood pressure substantially , with greater effects in combination than singly . Long-term health benefits will depend on the ability of people to make long-lasting dietary changes and the increased availability of lower-sodium foods 31 patients with a diastolic blood-pressure between 95 and 109 mm Hg have been treated for two years with a regimen involving a moderate restriction of salt in the diet . The results are compared with those in a control group and in a drug-treated group .  Salt restriction has reduced the diastolic blood-pressure by 7.3+/-1.6 mm Hg , a result similar to that in patients treated with antihypertensive drugs . In the untreated group the diastolic blood-pressure rose by 1.8+/-1.1 mm Hg . Most patients did not achieve the desired amount of salt restriction and a stricter adherence to the diet might have caused further falls in blood-pressure . Excessive salt intake is probably a major cause of the epidemic of hypertension in " civilised " countries and a reduction in salt intake may help to control the epidemic . In persons with a diastolic blood-pressure between 
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The relationship of blood pressure ( BP ) with stroke is direct and progressive throughout the range of usual BP , starting at a level of ≈115/75 mm Hg.4 It has been estimated that elevated BP accounts for 54 % of stroke and 47 % of coronary heart disease events.5 It is noteworthy that about half of these events occur in persons without hypertension .