***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 The US National Institutes of Health ( NIH ) and Centers for Medicare and Medicaid Services ( CMS ) sponsored a r and omized clinical trial comparing six versus three times per week in-center hemodialysis ( the Frequent Hemodialysis Network [ FHN ] Daily Trial ) , to test the effects of frequent hemodialysis on an array of intermediate outcomes . Herein we report challenges to enrollment and r and omization into the trial . METHODS Screening and enrollment was tracked at all participating dialysis clinics and specific reasons for dropout after baseline assessment were recorded for all enrolled subjects . Reasons for consent refusal were recorded in a subset of ( 10 out of 65 ) sites . RESULTS The trial screened 6276 hemodialysis patients on three times weekly hemodialysis in 65 hemodialysis clinics , 3481 ( 55 % ) were considered eligible for enrollment , and 3124 ( 90 % ) were approached for consent ; 378 ( 12 % ) consented and 245 were r and omized ( 65 % of those enrolled ) . Prospect i ve subjects chose not to participate primarily because of the anticipated time required for three extra treatments per week and the difficulties in following the protocol . CONCLUSIONS Recruitment into the FHN Daily Trial proved challenging but the goal of 250 r and omized subjects was almost met Provider and patient enthusiasm for  frequent home nocturnal hemodialysis ( FHNHD )  has been renewed ; however , the cost-effectiveness of this technique is unknown . We performed a cost-utility analysis of FHNHD compared with conventional hemodialysis ( CvHD ; 4 hours three times per week ) from a health payer perspective over a lifetime horizon using patient information from the Alberta NHD r and omized controlled trial .  Costs , including training costs , were obtained using microcosting and administrative data ( CAN$2012 ) . We determined the incremental cost per quality -adjusted life year ( QALY ) gained . Robustness was assessed using scenario , sensitivity , and probabilistic sensitivity analyses . Compared with CvHD ( 61 % in-center , 14 % satellite , and 25 % home dialysis ) , FHNHD led to incremental cost savings ( -$6700 ) and an additional 0.38 QALYs . In sensitivity analyses , when the annual probability of technique failure with FHNHD increased from 7.6 % ( reference case ) to ≥19 % , FHNHD became unattractive ( > $ 75,000/QALY ) . The cost/QALY gained became $ 13,000 if average training time for FHNHD increased from 3.7 to 6 weeks . In scenarios with alternate comparator modalities , FHNHD remained dominant compared with in-center CvHD ; cost/QALYs gained were $ 18,500 , $ 198,000 , and $ 423,000 compared with satellite CvHD , home CvHD , and peritoneal dialysis , respectively . In summary , FHNHD is attractive compared with in-center CvHD in this cohort . However , the attractiveness of FHNHD varies by technique failure rate , training time , and dialysis modalities from which patients are drawn , and these variables should be considered when establishing FHNHD programs BACKGROUND In this r and omized clinical trial , we aim ed to determine whether increasing the frequency of in-center hemodialysis would result in beneficial changes in left ventricular mass , self-reported physical health , and other intermediate outcomes among patients undergoing maintenance hemodialysis . METHODS Patients were r and omly assigned to undergo hemodialysis six times per week  ( frequent hemodialysis , 125 patients ) or three times per week  ( conventional hemodialysis , 120 patients ) for 12 months . The two co primary composite outcomes were death or change ( from baseline to 12 months ) in left ventricular mass , as assessed by cardiac magnetic resonance imaging , and death or change in the physical-health composite score of the R AND 36-item health survey . Secondary outcomes included cognitive performance ; self-reported depression ; laboratory markers of nutrition , mineral metabolism , and anemia ; blood pressure ; and rates of hospitalization and of interventions related to vascular access . RESULTS Patients in the frequent-hemodialysis group averaged 5.2 sessions per week ; the weekly st and ard Kt/V(urea ) ( the product of the urea clearance and the duration of the dialysis session normalized to the volume of distribution of urea ) was significantly higher in the frequent-hemodialysis group than in the conventional-hemodialysis group ( 3.54±0.56 vs. 2.49±0.27 ) . Frequent hemodialysis was associated with significant benefits with respect to both co primary composite outcomes ( hazard ratio for death or increase in left ventricular mass , 0.61 ; 95 % confidence interval [ CI ] , 0.46 to 0.82 ; hazard ratio for death or a decrease in the physical-health composite score , 0.70 ; 95 % CI , 0.53 to 0.92 ) . Patients r and omly assigned to frequent hemodialysis were more likely to undergo interventions related to vascular access than were patients assigned to conventional hemodialysis ( hazard ratio , 1.71 ; 95 % CI , 1.08 to 2.73 ) . Frequent hemodialysis was associated with improved control of hypertension and hyperphosphatemia . There were no significant effects of frequent hemodialysis  on cognitive performance , self-reported depression , serum albumin concentration , or use of erythropoiesis-stimulating agents . CONCLUSIONS Frequent hemodialysis , as compared with conventional hemodialysis , was associated with favorable results with respect to the composite outcomes of death or change in left ventricular mass and death or change in a physical-health composite score but prompted more frequent interventions related to vascular access . ( Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others ; Clinical Trials.gov number , NCT00264758 . ) Background Left ventricular ( LV ) hypertrophy is common among patients on hemodialysis . While a relationship between blood pressure ( BP ) and LV hypertrophy has been established , it is unclear which BP measurement method is the strongest correlate of LV hypertrophy . We sought to determine agreement between various blood pressure measurement methods , as well as identify which method was the strongest correlate of LV hypertrophy among patients on hemodialysis . Methods This was a post-hoc analysis of data from a r and omized controlled trial . We evaluated the agreement between seven BP measurement methods : st and ardized measurement at baseline ; single pre- and post-dialysis , as well as mean intra-dialytic measurement at baseline ; and cumulative pre- , intra- and post-dialysis readings ( an average of 12 monthly readings based on a single day per month ) . Agreement was assessed using Lin 's concordance correlation coefficient ( CCC ) and the Bl and Altman method . Association between BP measurement method and LV hypertrophy on baseline cardiac MRI was determined using receiver operating characteristic curves and area under the curve ( AUC ) . Results Agreement between BP measurement methods in the 39 patients on hemodialysis varied considerably , from a CCC of 0.35 to 0.94 , with overlapping 95 % confidence intervals . Pre-dialysis measurements were the weakest predictors of LV hypertrophy while st and ardized , post- and inter-dialytic measurements had similar and strong ( AUC 0.79 to 0.80 ) predictive power for LV hypertrophy . Conclusions A single st and ardized BP has strong predictive power for LV hypertrophy and performs just as well as more re source intensive cumulative measurements , whereas pre-dialysis blood pressure measurements have the weakest predictive power for LV hypertrophy . Current guidelines , which recommend using pre-dialysis measurements , should be revisited to confirm these results CONTEXT Morbidity and mortality rates in hemodialysis patients remain excessive . Alterations in the delivery of dialysis may lead to improved patient outcomes . OBJECTIVE To compare the effects of frequent nocturnal hemodialysis vs conventional hemodialysis on change in left ventricular mass and health-related quality of life over 6 months . DESIGN , SETTING , AND PARTICIPANTS A 2-group , parallel , r and omized controlled trial conducted at 2 Canadian university centers between August 2004 and December 2006 . A total of 52 patients undergoing hemodialysis were recruited . INTERVENTION Participants were r and omly assigned in a 1:1 ratio to receive nocturnal hemodialysis 6 times weekly or conventional hemodialysis 3 times weekly . MAIN OUTCOME MEASURES The primary outcome was change in left ventricular mass , as measured by cardiovascular magnetic resonance imaging . The secondary outcomes were patient-reported quality of life , blood pressure , mineral metabolism , and use of medications . RESULTS Frequent nocturnal hemodialysis significantly improved the primary outcome ( mean left ventricular mass difference between groups , 15.3 g , 95 % confidence interval [ CI ] , 1.0 to 29.6 g ; P = .04 ) . Frequent nocturnal hemodialysis did not significantly improve quality of life ( difference of change in EuroQol 5-D index from baseline , 0.05 ; 95 % CI , -0.07 to 0.17 ; P = .43 ) . However , frequent nocturnal hemodialysis was associated with clinical ly and statistically significant improvements in selected kidney-specific domains of quality of life ( P = .01 for effects of kidney disease and P = .02 for burden of kidney disease ) . Frequent nocturnal hemodialysis was also associated with improvements in systolic blood pressure ( P = .01 after adjustment ) and mineral metabolism , including a reduction in or discontinuation of antihypertensive medications ( 16/26 patients in the nocturnal hemodialysis group vs 3/25 patients in the conventional hemodialysis group ; P < .001 ) and oral phosphate binders ( 19/26 patients in the nocturnal hemodialysis group vs 3/25 patients in the conventional dialysis group ; P < .001 ) . No benefit in anemia management was seen with nocturnal hemodialysis . CONCLUSION This preliminary study revealed that , compared with conventional hemodialysis ( 3 times weekly ) , frequent nocturnal hemodialysis improved left ventricular mass , reduced the need for blood pressure medications , improved some measures of mineral metabolism , and improved selected measures of quality of life . TRIAL REGISTRATION is rct n.org Identifier : IS RCT N25858715 BACKGROUND The annual mortality rate for maintenance hemodialysis patients in the United States is unacceptably high at 15%-20 % . In 2004 , we initiated the Frequent Hemodialysis Network ( FHN ) clinical trials . This report presents baseline characteristics of FHN Trial participants and compares them with hemodialysis patients tracked in US Renal Data System ( USRDS ) data . STUDY DESIGN 2 separate r and omized clinical trials . SETTING S & PARTICIPANTS FHN includes 332 patients with chronic kidney disease requiring long-term dialysis therapy enrolled in 2 separate r and omized clinical trials . The FHN Daily Trial ( 245 r and omly assigned participants ) was design ed to compare outcomes of 6-times-weekly in-center daily hemodialysis ( 1.5 - 2.75 h/session ) with conventional 3-times-weekly in-center hemodialysis . The FHN Nocturnal Trial ( 87 r and omly assigned participants ) was design ed to compare outcomes of 6-times-weekly home nocturnal ( 6 - 8 h/session ) with conventional 3-times-weekly hemodialysis . USRDS data include 338,109 incident and prevalent long-term hemodialysis patients from the calendar year 2007 . RESULTS Participants in both trials were on average younger than the average hemodialysis patient in the United States ( Daily Trial , 50.4 years ; P < 0.001 ; Nocturnal Trial , 52.8 years ; P < 0.001 ) . Compared with USRDS data , whites were under-represented in the Daily Trial ( 36 % vs 55 % ; P < 0.001 ) , whereas Hispanics were under-represented in the Nocturnal Trial and over-represented in the Daily Trial ( 0 % vs 28 % ; P < 0.001 ) . In addition , there were more fistulas and fewer catheters in the Daily Trial ( 61 % and 20 % , respectively ; P < 0.001 for both ) and fewer grafts and more catheters in the Nocturnal Trial ( 10 % and 44 % , respectively ; P < 0.005 for both ) . LIMITATIONS Clinical trial exclusion criteria and patient willingness to participate limit comparisons with the USRDS . CONCLUSIONS FHN participants were younger and the racial composition for each study was different from the racial composition of the aggregate US dialysis population . Catheters for vascular access were more common in FHN Nocturnal Trial participants We investigated the effects of frequency of  hemodialysis  on nutritional status by analyzing the data in the Frequent Hemodialysis Network Trial . We compared changes in albumin , body weight and composition among 245 patients r and omized to 6- or 3-times per week in-center hemodial 
    Output:
    
Overall , home haemodialysis  reduced 24 hour ambulatory blood pressure and improved uraemic symptoms , but increased treatment-related burden of disease and interference in social activities .