***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 Angiotensin-converting enzyme ( ACE ) inhibitors , which are frequently administered in patients with heart disease , have a known inhibitory effect on erythropoiesis . The aim of this study was to detect whether early ACE inhibitor administration slows recovery from anemia following recent cardiac surgery . METHODS AND RESULTS Forty male patients with anemia ( hemoglobin < 12 g/dL ) an average of 9 days after cardiac surgery were r and omized to receive enalapril ( ACE inhibitor group ) or not . All of the patients received ferrous sulfate , 525 mg , in addition to st and ard therapy .  Patients with anemia due to other causes were excluded . Blood sample s were obtained at baseline , and after 8 days , 16 days , and 60 days . A 6-min walking test and echocardioscan were performed at baseline , and after 16 days and 60 days of treatment , and a chest radiograph was obtained at baseline and after 60 days . The ACE inhibitor group showed a statistically significant lower increase in hemoglobin and RBC values . The peak between-group differences of 1 g/dL of hemoglobin ( p = 0.012 ) and 444 RBCs per milliliter ( p = 0.017 ) were observed on day 16 . CONCLUSIONS Early enalapril maleate administration in anemic patients after heart surgery significantly inhibits erythropoiesis . This unfavorable effect on anemia should be considered when prescribing ACE inhibitors for such patients OBJECTIVES This study sought to examine whether the cardioprotective effects of angiotensin-converting enzyme ( ACE ) inhibitor therapy by perindopril are modified by renal function in patients with stable coronary artery disease . BACKGROUND A recent study reported that an impaired renal function identified a subgroup of patients with stable coronary artery disease more likely to benefit from ACE inhibition therapy . In light of the growing interest in tailored therapy for targeting medications to specific subgroups , remarks on the consistency of the treatment effect by ACE inhibitors are highly important . METHODS The present study involved 12,056 patients with stable coronary artery disease without heart failure r and omized to perindopril or placebo .  Estimated glomerular filtration rate ( eGFR ) was calculated using the abbreviated Modification of Diet in Renal Disease equation . Cox regression analysis was used to estimate multivariable-adjusted hazard ratios . RESULTS The mean eGFR was 76.2 ( + /-18.1 ) ml/min/1.73 m2 . During follow-up , the primary end point ( cardiovascular death , nonfatal myocardial infa rct ion , or resuscitated cardiac arrest ) occurred in 454 of 5,761 patients ( 7.9 % ) with eGFR > or = 75 and in 631 of 6,295 patients ( 10.0 % ) with eGFR < 75 . Treatment benefits of perindopril were apparent in both patient groups either with eGFR > or = 75 ( hazard ratio 0.77 ; 95 % confidence interval 0.64 to 0.93 ) or eGFR < 75 ( hazard ratio 0.84 ; 95 % confidence interval 0.72 to 0.98 ) . We observed no significant interaction between renal function and treatment benefit ( p = 0.47 ) . Using different cutoff points of eGFR at the level of 60 or 90 result ed in similar trends . CONCLUSIONS The treatment benefit of perindopril is consistent and not modified by mild to moderate renal insufficiency Background —Although previous work has suggested that anemia is associated with an increased mortality in selected patients with congestive heart failure ( CHF ) , little is known about the prevalence and predictors of anemia , or whether anemia is an independent prognostic factor in unselected , community-based patients with CHF . Methods and Results —We analyzed a population -based cohort of patients with new-onset CHF from a data base of patients discharged from 138 acute-care hospitals in Alberta , Canada , between April 1993 and March 2001 .  Logistic regression , Kaplan-Meier survival analyses , and Cox proportional hazards model were used . Among the 12 065 patients with CHF ( median age 78 years ) , 17 % had anemia , 58 % of whom had anemia of chronic disease . After adjustment for clinical and demographic variables , patients with anemia were more likely to be older ( odds ratio [ OR ] 1.01 per year ) and female ( OR 1.2 [ 95 % confidence interval 1.1 to 1.3 ] ) and to have a history of chronic renal insufficiency ( OR=3.2 [ 95 % confidence interval 2.8 to 3.6 ] ) , or hypertension ( OR 1.3 [ 95 % confidence interval 1.2 to 1.5 ] ) . Hazard ratios for mortality , adjusting for covariates , were 1.34 ( 1.24 to 1.46 ) in anemic patients , and 1.36 ( 1.23 to 1.50 ) in those patients with anemia of chronic disease . Conclusions —In this large cohort of community-dwelling patients with CHF , anemia is common and an independent prognostic factor for mortality . Further research into the mechanisms of anemia in CHF and r and omized controlled trials to test whether correction of anemia improves prognosis in CHF are needed BACKGROUND Angiotensin-converting-enzyme ( ACE ) inhibitors reduce packed cell volume and haemoglobin concentration in polycythaemia that follows renal transplantation , which , like altitude polycythaemia , is an erythropoietin-dependent form of polycythaemia . We aim ed to establish the effect of ACE-inhibitor treatment in people with altitude polycythaemia . METHODS We did a prospect i ve r and omised study in 26 people with altitude polycythaemia ( packed cell volume > or = 55 % ) and 24-h rate of urinary protein excretion greater than 150 mg , who had been referred to the Renal Disease Project in La Paz , Bolivia . 13 participants were assigned 5 mg/day enalapril for 2 years ( study group ) , and 13  no treatment ( controls ) . Blood pressure , packed cell volume and haemoglobin concentration , proteinuria , and renal function were compared by intention-to-treat analyses . FINDINGS Baseline packed cell volume and haemoglobin concentration were positively correlated with bodyweight ( p=0.02 ) , systolic ( p=0.01 ) and diastolic ( p=0.04 ) blood pressure , serum creatinine ( p=0.009 ) , blood urea ( p=0.008 ) , and proteinuria ( p=0.003 ) . Systolic and diastolic blood pressure remained stable in the study group , but increased in controls . In study patients , mean ( SD ) packed cell volume , haemoglobin concentration , and proteinuria fell from 63.5 % ( 4.9 ) to 56.8 % ( 4.1 ) , p<0.0001 ; 207 ( 18 ) to 164 g/L ( 13 ) , p<0,0001 ; and from 358.6 ( 260.3 ) to 247.7 mg/24-h ( 208.2 ) , p<0.002 , respectively , but did not change significantly in controls . At 12 and 24 months of follow-up , packed cell volume , haemoglobin concentration , and proteinuria differed significantly between the groups ( p<0.0001 for each comparison ) . In study patients , follow-up changes in packed cell volume ( r=0.88 , p<0.0001 ) or haemoglobin concentration ( r=0.83 , p<0.0001 ) and proteinuria were strongly correlated . Enalapril was well tolerated by all patients . INTERPRETATION ACE-inhibition therapy effectively and safely ameliorates altitude polycythaemia and reduces proteinuria OBJECTIVES We aim ed to investigate the impact of angiotensin-converting enzyme inhibitors ( ACEIs ) on hematocrit values in those with heart failure , and the relationship between incident anemia and mortality . BACKGROUND Prevalent anemia is an independent risk factor for morbidity and mortality in those with heart failure . Studies in patients with polycythemia have demonstrated that ACEIs are effective in lowering hematocrit values . METHODS We used the Studies Of Left Ventricular Dysfunction ( SOLVD ) data base to compare the odds of developing new anemia at one year in patients who were not anemic at entry and who were r and omized to enalapril or placebo .  Cox proportional hazards models were utilized to determine the impact of incident and prevalent anemia on subsequent mortality . RESULTS Enalapril increased the odds of incident anemia ( hematocrit < or = 39 % in men or < or = 36 % in women ) at one year by 48 % ( odds ratio [ OR ] 1.48 , 95 % confidence interval [ CI ] 1.20 to 1.82 ) in unadjusted and 56 % ( OR 1.56 , 95 % CI 1.26 to 1.93 ) in adjusted models . With multivariate analysis , prevalent anemia at r and omization was associated with a 44 % ( hazard ratio [ HR ] 1.44 , 95 % CI 1.31 to 1.66 ) increase in all-cause mortality , whereas incident anemia after r and omization was associated with a 108 % increase ( HR 2.08 , 95 % CI 1.82 to 2.38 ) . After adjusting for incident and prevalent anemia , use of enalapril was associated with a survival benefit . CONCLUSIONS Enalapril was associated with increased odds of developing anemia at one year . Those with periods of time with incident anemia had the poorest survival , followed by those with prevalent anemia , then those without anemia . Enalapril was protective of overall mortality after adjusting for incident anemia and in those with prevalent anemia Objective To investigate the association between sustained postoperative anaemia and outcome after coronary artery bypass graft ( CABG ) surgery . Design Retrospective analysis of the IMAGINE trial , which tested the effect of the ACE inhibitor quinapril on cardiovascular events after CABG . Setting Thoracic surgery clinic/outpatient department . Patients 2553 stable patients with left ventricular ejection fraction > 40 % 2–7 days after scheduled CABG . Interventions R and omisation to quinapril or placebo . Main outcome measures Cox regression analysis for the association between postoperative anaemia and cardiovascular events and the effect of quinapril on the incidence of anaemia . Results Postoperative anaemia was sustained for > 50 days in 44 % of patients . Sustained postoperative anaemia was associated with an increased incidence of cardiovascular events during the first 3 months ( adjusted HR ( adjHR ) 1.77 , 95 % CI 1.10 to 2.85 , p=0.012 ) and during the maximum follow-up of 43 months ( adjHR 1.37 , 95 % CI 1.14 to 1.65 , p=0.008 ) . When haemoglobin ( Hb ) was considered as a continuous variable , every 1 mg/dl decrease in Hb was associated with a 13 % increase in cardiovascular events ( adjHR 0.87 , 95 % CI 0.81 to 0.95 , p=0.003 ) and a 22 % increase in all-cause mortality ( adjHR 0.78 , 95 % CI 0.60 to 0.99 , p=0.034 ) . Quinapril was associated with a slower postoperative recovery of Hb levels and a higher incidence of cardiovascular events in patients with anaemia ( adjHR 1.60 , 95 % CI 1.1 to 2.4 , p=0.024 ) . Conclusions Postoperative anaemia is common , frequently persists for months after CABG surgery and is associated with an impaired outcome . In patients with anaemia , ACE inhibitors slowed recovery from postoperative anaemia and increased the incidence of cardiovascular events after CABG INTRODUCTION Although anaemia is associated with an adverse prognosis in congestive heart failure ( HF ) , the cause of the anaemia and its relationship to non-cardiac and cardiac complications needs to be better defined , particularly in a general community population . METHODS Clinical data were collected prospect ively from 959 patients hospitalised with HF . RESULTS Thirty-eight percent ( n=369 ) had anaemia ( Hb<120 g/L ) , which was normochromic normocytic in 87.8 % . Of those who had haematinic studies , 15.5 % had a confirmed haematinic deficiency . Anaemic patients were of similar age to non-anaemic ( 79 vs 77 years ) but were more likely to have elevated creatinine ( 48 vs 29 % , p<0.001 ) , hyponatremia ( 20 vs 15 % , p=0.05 ) , and LVEF>40 % ( 49 vs 39 % , p=0.004 ) 
    Output:
    
Our meta- analysis demonstrates an association between anemia and the use of RAS inhibitors .