a direct renin inhibitor ( dri ) , aliskiren , was developed by structure - based design as the 
 first inhibitor of the catalytic effect of renin a decade ago ) hypertension is one of the serious problems in dialysis patients , and lowering blood 
 pressure ( bp ) results in improved patient survival ) in maintenance hemodialysis patients of toride kyodo general hospital , ten hypertensive 
 patients with a urine volume of less than 100 ml / day , and undergoing thrice a week 
 hemodialysis therapy were enrolled in this study after their informed consent was verbally 
 obtained with respect to administration of aliskiren , the purpose and the results of 
 examinations and the disclosure of obtained data that could not specify the individual 
 private information . as table 1table 1patient characteristicscasesexagedialysis period ( month)diseasebpsystolicdiastolicmean1f66171cgn186741112m69132arf by unknown cause183881203f67144cgn188961264m5628dm176941215m6232dm1821011286m43251reflux nephropathy1731021267m62156cgn172991238m61147cgn163991219m7232dm1607610410m6783dm16994119totalm : f 8:263  8118  73175  1092 10120  7 shows , the patients were 8 males and 2 females who were 63  8 ( 43 - 72 ) years 
 old . the period of dialysis in the patients was 118  73 ( 28 - 251 ) months . the causes of 
 renal failure were cgn in 4 cases , diabetes mellitus in 4 cases , reflux nephropathy in 1 
 case and renal failure with acute - onset and unknown etiology in 1 case . bp of the patients 
 was measured in the supine position on a bed before each dialysis session . before initiating 
 aliskiren , the patients ' averaged systolic , diastolic , and mean bps taken at the start of 
 each hd sessions for 2 weeks ( 6 sessions ) were 175  10 , 92  10 and 120  7 mmhg , 
 respectively . they had already received 3  2 ( 0 - 7 ) antihypertensive drugs before 
 aliskiren treatment ( table 2 
 table 2pra , pac and antihypertensive drugs before aliskiren therapycasepra(ng / ml / hour)pac(pg / ml)drugs18.13543 : cab,1b , arb20.254.87 : cab , 1b , 2s , b , acei , arb  230.82432 : cab , arb45.352.24 : cab , 1b , acei , arb52.61342 : cab , 1b69.651.32 : cab , arb74.294.94 : cab  2 , b , arb80.7154098.977.53 : cab  2 , arb104.761.83 : cab  2 , arbtotal4.5  3.5127.8  100.03  2cab : calcium blockers , 1b : 1-blockers , arb : angiotensin - ii receptor blockers , acei : 
 angiotensin converting enzyme inhibitors , b : -blockers . the actual prescribed drugs 
 were nifedipine ( n ) , doxazosin ( d ) and telmisartan ( t ) in case 1 ; n , d , guanabenz , 
 atenolol , enalapril , olmesartan ( o ) and valsaratan ( v ) in case 2 ; n and t in case 3 ; 
 n , d , t and v in case 4 ; amlodipine ( a ) and d in case 5 ; n and o in case 6 ; 
 manidipine , n , celiprolol and o in case 7 ; azelnidipine , n and candesartan in case 9 ; 
 and cilnidipine , a and t in case 10 . ) . blood samples for measuring serum potassium ( k ) , plasma renin activity 
 ( pra ) , plasma aldosterone concentration ( pac ) and plasma prorenin were obtained through the 
 blood accesses for hemodialysis 30 minutes after beginning bed rest and just before each 
 dialysis session . pra was measured by the established enzyme activity assay using 
 angiotensinogen as an enzyme substrate ) cab : calcium blockers , 1b : 1-blockers , arb : angiotensin - ii receptor blockers , acei : 
 angiotensin converting enzyme inhibitors , b : -blockers . the actual prescribed drugs 
 were nifedipine ( n ) , doxazosin ( d ) and telmisartan ( t ) in case 1 ; n , d , guanabenz , 
 atenolol , enalapril , olmesartan ( o ) and valsaratan ( v ) in case 2 ; n and t in case 3 ; 
 n , d , t and v in case 4 ; amlodipine ( a ) and d in case 5 ; n and o in case 6 ; 
 manidipine , n , celiprolol and o in case 7 ; azelnidipine , n and candesartan in case 9 ; 
 and cilnidipine , a and t in case 10 . aliskiren , 150 mg / day as an initial dose , was orally administered to the patients after 
 every evening meal to avoid hypotension during hd sessions and to improve adherence to the 
 drug by the simple prescription style . the averaged systolic , diastolic , and mean bps at the beginning 
 of the hd sessions for 2 weeks after aliskiren therapy were compared with the bps before 
 initiating aliskiren . two weeks are supposed to be a sufficient period for aliskiren to 
 reach to its plateau levels . in 4 patients , a few antihypertensive drugs other than 
 aliskiren were discontinued within 2 weeks , because of hypotension that caused difficulties 
 in continuing hd therapy . to compare the effect of aliskiren on bp in these four patients 
 with the other six patients , the score for the bp lowering effect was counted , as described 
 below . the score for the bp lowering effect = ( averaged lowering of the mean bp in mmhg for two 
 weeks ) + ( 10 mmhg x reduced daily tablets or capsules of antihypertensive drugs ) after 
 aliskiren treatment . for instance , if the averaged lowering of the mean bp for two weeks by the administration 
 of aliskiren is 10 mmhg and one tablet of an antihypertensive drug can be discontinued 
 during that period , the score for the bp lowering effect will be calculated as follows , the data are shown as the mean  sd , unless otherwise specified . the paired 
 t - test and regression analysis were performed using excel 2007 ( microsoft 
 inc . , sbp , dbp , and mbp indicate the differences of after and before administration of 
 aliskiren for the systolic , diastolic , and mean blood pressure , respectively . the score for the bp lowering effect was calculated as 
 the sum of the reduced mean blood pressure in mmhg and discontinued antihypertensive 
 drugs , where 1 tablet ( t ) or capsule ( c ) per day was assumed to be equal to a 10-mmhg 
 reduction in blood pressure , as in ( 2 + 2 )  3 / 7 = 1.7 in case 3 . since the blood 
 pressure was rather elevated ( + 2 mmhg ) , the score for the bp lowering effect was 
 calculated as follows , 1.7  10  2 = 15 ( see the formula in the text ) . administration of aliskiren to the ten anuric hd patients 
 significantly suppressed the systolic , mean and diastolic bp before hd sessions ( figure 1figure 1effect of aliskiren on bp . systolic , mean , and diastolic bp were averaged for before 
 and after administration of aliskiren for 2 weeks ( 6 measurements before hd sessions ) . * : p < 0.05 . * * : p < 0.01 . ) , and reduced the administered doses of antihypertensives in 4 patients . the averaged 
 bps before / after aliskiren treatment were 175  10 / 171  11 mmhg for systolic , 120  7 / 
 116  10 mmhg for the mean and 93  10 / 88  13 mmhg for diastolic . in 6 patients without 
 changing antihypertensives , these bps were 172  11 / 167  12 mmhg for systolic , 117  8 / 
 111  10 mmhg for the mean and 89  12 / 83  14 mmhg for diastolic . the total effect of aliskiren was estimated by calculating 
 the scores for the bp lowering effect and summarized in table 2 . systolic , mean , and diastolic bp were averaged for before 
 and after administration of aliskiren for 2 weeks ( 6 measurements before hd sessions ) . shows , serum k and pac were not significantly changed by administrating aliskiren . 
 meanwhile , pra was significantly suppressed . the level of pra or pac before aliskiren treatment did not predict the overall effect 
 ( figure 3figure 3pra , pac before treatment and prorenin after treatment and their correlation with the 
 score for the bp lowering effect . the 
 correlation coefficients of the score and pra , pac and prorenin were 0.06 , 0.21 and 
 0.08 , respectively . ) . however , a pecent reduction rate of ( pra  pac ) , calculated by the formula 
 described below , above 80% may reflect the effectiveness of aliskiren ( figure 4figure 4reduction rate of ( pra  pac ) and the score for the bp lowering effect . these values 
 were not significantly correlated ( y = 0.12x  0.78 , r = 0.44 , p = 0.20 ) , but high bp 
 lowering effects ( score > 5 ) were observed only in the cases showing a high percent 
 reduction rate ( > 80% ) . ) . percent reduction rate of ( pra  pac ) = 100  { ( pra  pac)before ( pra 
  pac)after}/(pra  pac)before , where before and after indicate before 
 and after the administration of aliskiren , respectively . pra , pac before treatment and prorenin after treatment and their correlation with the 
 score for the bp lowering effect . the 
 correlation coefficients of the score and pra , pac and prorenin were 0.06 , 0.21 and 
 0.08 , respectively . reduction rate of ( pra  pac ) and the score for the bp lowering effect . these values 
 were not significantly correlated ( y = 0.12x  0.78 , r = 0.44 , p = 0.20 ) , but high bp 
 lowering effects ( score > 5 ) were observed only in the cases showing a high percent 
 reduction rate ( > 80% ) . no adverse reaction after administration of aliskiren was observed during the observation 
 period , except for arm pain caused by hypotension in one patient who continued to receive 
 aliskiren . lowering bp is not always beneficial to hd patients because hd would be more easily carried 
 out in a hypertensive , rather than hypotensive , condition . to avoid such troubles related to 
 hypotension during hd sessions , anti - hypertensives except for aliskiren , this protocol caused a difficulty in analyzing the real effect of 
 aliskiren on bp . we assumed a reduction of one tablet or capsule in a day , irrespective of 
 the kinds of drugs , was equivalent to lowering bp by 10 mmhg , which seemed an anticipated 
 level for physicians to prescribe a new antihypertensive drug . otherwise , the effect of 
 aliskiren in a study population could not be evaluated as a whole , and the patients should 
 be separated into two populations : one in whom the prescribed antihypertensives are reduced 
 and another in whom the drugs are not changed . apparently , the former group includes 
 patients with a better response to aliskiren . moreover , such a protocol inevitably decreases 
 the size of the population for analysis . therefore , we proposed a score for the bp lowering 
 effect as an index for evaluating the effect of alskiren in patients receiving hemodialysis 
 therapy . based on the score for the bp lowering effect , the dri , aliskiren , was certainly useful as 
 an antihypertensive in dialysis patients , although the function and regulation of the ras in 
 dialysis patients are inconsistent and have not been fully elucidated ) since pra did not predict the effectiveness of aliskiren in a previous 
 report ) in conclusion , a dri , aliskiren , was effective in lowering bp in anuric dialysis patients . further studies are needed to elucidate the mechanism and to select patients responsive to 
 aliskiren . the first author , y. maeda , received honoraria from novartis ( basel , switzerland ) for 
 serving as a speaker .
objective : a direct renin - inhibitor ( dri ) , aliskiren , was administered to 
 anuric patients to investigate whether it can be a new optional therapy against 
 hypertension in hemodialysis ( hd ) patients.patients : the patients that received aliskiren comprised 8 males and 2 
 females with a mean  sd age of 63  8 years ( 43 - 72 years ) . they were exposed to dialysis 
 therapy for 118  73 months ( 8 - 251 months ) , with diabetes mellitus in 4 cases , chronic 
 glomerulonephritis in 4 cases , and other diagnoses in 2 cases.methods : after the plasma renin activity ( pra ) and plasma aldosterone 
 concentration ( pac ) were measured before an hd session , aliskiren , 150 mg as an initial 
 dose , was administered to the patients . 
 pra and pac were also examined a week after 
 initiating aliskiren . the blood pressure ( bp ) levels at the start of each hd session for a 
 period of 2 weeks ( 6 hd sessions ) 
 were compared between before and after administration of 
 aliskiren . 
 the change of doses in other antihypertensive agents was also counted.results : the averaged reduction of mean blood pressure was 4  5 mmhg , and 
 doses of antihypertensives other than aliskiren were reduced in 4 patients . of the 
 examined parameters , only the reduction rate of pra x pac seemed correlated with the bp 
 lowering effect of aliskiren , which was calculated as the sum of the mean bp reduction in 
 mmhg and drug reduction with 
 1 tablet ( capsule)/day considered to be 10 mmhg.conclusion : a dri , aliskiren , was effective even in anuric dialysis 
 patients , and monitoring of pra and pac was valuable for selecting cases responsive to 
 aliskiren .