Predialysis BP Research Articles

WHITE-COAT AND MASKED HYPERTENSION IN HEMODIALYSIS PATIENTS

Objective: Unlike the general population or patients with earlier stages of chronic kidney disease, there are no clear diagnostic criteria for white-coat and masked hypertension in the hemodialysis population. In the present study, we aimed to estimate the prevalence of these 2 BP phenotypes using routine predialysis BP recordings in combination with 44-hour ambulatory BP monitoring (ABPM). Design and method: In a cohort of 70 hemodialysis patients, hypertension was assessed with 2 methods: (i) the average of routine predialysis BP recordings over 6 consecuitive dialysis sessions; (ii) ABPM over an entire 44-hour interdialytic period (BP measurements at 20-minute intervals; Microlife WatchBP O3 device). The thresholds of 140/90 mmHg and 130/80 mmHg were used to define abnormal predialysis and ambulatory BP, respectively. Results: Study participants (45 males and 25 females) had a mean age of 65.3±13.3 years and a median dialysis vintage of 15 months. The prevalence of hypertension was 88.6% by predialysis BP recordings and 90% by ABPM. In all, 61 patients were being treated with an average of 1.5±0.6 antihypertensive medications daily. In all, 51.4% of patients had either normotension or adequately controlled hypertension confirmed by the 2 different BP monitoring techniques, whereas 18.6% of patients had uncontrolled hypertension confirmed by both techniques. The prevalence of white-coat hypertension was 24.3% and the prevalence of masked hypertension was 5.7%. A 2-week averaged routine predialysis BP at the threshold of 140/90 mmHg provided 77.8% sensitivity and 30.8% specificity for the diagnosis of an average 44-hour ambulatory BPequal or higher than 130/80 mmHg. The agreement between these 2 techniques for the identification of patients with adequately controlled hypertension was poor (k-statistic: 0.378, P<0.001). Conclusions: This study shows that in approximately 30% of hemodialysis patients, there is lack of concordance between routine predialysis BP recordings and ABPM for the determination of BP control status. Routine predialysis BP recordings, even when averaged over 6 consecutive dialysis sessions, are inaccurate estimates of the actual BP load, as assessed by ABPM.

Clinical characteristics and management of hemodialysis patients with pre-dialysis hypertension: a multicenter observational study

Background Hypertension is a leading preventable risk factor for cardiovascular disease in hemodialysis patients. Pre-dialysis systolic blood pressure (SBP) more than 160 mmHg was thought to be associated with increased risk of cardiovascular events and all-cause mortality. The present study was performed to explore the clinical characteristics and management of hemodialysis patients with pre-dialysis SBP ≥ 160 mmHg. Methods A total of 1233 patients undergoing hemodialysis from nine hemodialysis centers were enrolled. Pre-dialysis and home BP were measured and clinical data were collected. The characteristics of patients with pre-dialysis SBP ≥ 160 mmHg were explored. Clinical parameters between hypertensive and non-hypertensive patients were compared. The partial correlation analyses performed to identify the associations between BP and clinical parameters. Results There were 24.6% of the hemodialysis patients had pre-dialysis SBP ≥ 160 mmHg and the average SBP was 173.8 ± 10.9 mmHg. Only 21.4% of the patients achieved dry weight after dialysis and up to 30.2% of patients were not given combination therapies of antihypertensive drugs. Compared to patients with pre-hemodialysis SBP < 160 mmHg, patients with pre-dialysis SBP ≥ 160 mmHg had lower target-reaching rate of Kt/v and higher incidences of intradialytic hypotension and muscle spasm. Most patients (96%) with pre-dialysis SBP ≥ 160 mmHg had home SBP≥ 135 mmHg. Patients with home SBP ≥ 160 mmHg had higher left ventricular weight index and lower hemoglobin levels when compared to their counterparts with home SBP <160 mmHg. Conclusions Pre-dialysis SBP ≥ 160 mmHg is common in clinical practice and most of the patients could diagnosed to be hypertensive according to their home SBP. Patients with pre-dialysis SBP ≥ 160 mmHg are more likely to be subjected to dialysis insufficiency and intradialytic complications. Achieving dry weight and sufficient pharmacologic interventions should be strengthened to improve BP control in the hemodialysis population.

DIAGNOSTIC PERFORMANCE OF PRE-DIALYSIS AND AMBULATORY BLOOD PRESSURE LEVELS IN MEN AND WOMEN HEMODIALYSIS PATIENTS

Objective: Ambulatory-blood-pressure (BP) control is worse in men than in women with chronic kidney disease or kidney transplantation. So far no study assessed in parallel possible effects of sex differences on the prevalence, control, and BP phenotypes according to pre-dialysis and 48-h ABPM in hemodialysis patients. Further, no study has evaluated the diagnostic accuracy of pre-dialysis BP in men and women hemodialysis patients. Design and method: 129 male and 91 female hemodialysis patients that underwent 48-h ABPM with Mobil-O-Graph-NG were included in this analysis. Hypertension was defined as follows: (1)pre-dialysis BP greater than or equal to 140/90mmHg or use of antihypertensive agents, (2)48-h BP greater than or equal to 130/80mmHg or use of antihypertensive agents. Results: The prevalence of hypertension was not different between men and women with the use of pre-dialysis BP (92.2% vs 92.3%, p = 0.987, respectively) or 48-h ABPM (92.2% vs 89%, p = 0.411). With the use of pre-dialysis BP men had significantly lower control rates than women (18.5% vs 32.1%, p = 0.025); a similar pattern of worse control in men was apparent with ABPM, but the difference was not statistically significant (22.7% vs 28.4%, p = 0.360). The rate of patients with concordant lack of control by pre-dialysis and ABPM was significantly higher in men than women (65.3% vs 49.4%, p = 0.023); white-coat (14.9% vs 17.6%, p = 0.593) and masked hypertension (10.7% vs 18.8%, p = 0.101) did not differ between-groups. However, the misclassifation rate with the use of pre-dialysis BP was lower in men than women. There was moderate or at best fair agreement between pre-dialysis and ABPM with regards to the prevalence (men: kappa-statistics = 0.39, p &lt; 0.001 and women: 0.27, p = 0.011) and control rates (kappa-statistics = 0.25, p = 0.005 and 0.17, p = 0.124, respectively). Pre-dialysis BP greater than or equal to 140/90mmHg had sensitivity/specificity of 85.9%/51.4% in men and 72.4%/54.5% in women for the diagnosis of elevated 48-h BP. Receiver-operating-curve analyses confirmed this poor diagnostic performance. Conclusions: The prevalence of hypertension is similar between men and women hemodialysis patients but men have worse rates of office BP control. The diagnostic accuracy of pre-dialysis BP was equally poor in men and women hemodialysis patients.

BLOOD PRESSURE MONITORING IN HEMODIALYSIS PATIENTS: ARE IMPRECISE THE MEASURING PRE- AND POSTDIALYSIS OR INTERDIALYTIC AMBULATORY BP?

Objective: The optimal Blood Pressure in Hemodialysis are still unclear as to their value or measurement time and better hypotensive treatment. Some authors recommend BP &lt; 140/90 mmHg and &lt; 130/80 mmHg before and after HD respectively. There are an associations between predialysis systolic, diastolic and pulse pressure with all-cause mortality. Our objective is to assess the percentage of hypertensive patients in our hemodialysis unit after adjusting their dry weight and there is a difference between the pre and postdialysis blood pressure measurement. Design and method: We included 66 patients(N 66) hemodialysis unit, we have performed standardized BP measurements among hemodialysis patients, predialysis SBP/DBP, postdialysis SBP/DBP, pulse pressure and interdialytic BP assessed by ambulatory. Patients characteristics: (male [n 36] 54,5%), median age 68 yrs (R 29–90y), DM 25 patients (37,8%),nontraumatic amputation 10 patients (15%). Results: Predialysis SBP/DBP values &gt;140/90 mmHg was 50% (33 patients), 51,5% female. Predialysis Pulse pressure 82 mmHg Postdialysis SBP/DBP values &gt; 140/90 mmHg was 59% (39 patients), 54% female. Postdialysis Pulse pressure 83 mmHg Interdialytic BP value &gt; 140/90 mmHg was 50% (30 patients) and Pulse pressure 78 mmHg Group HT:DM 17 patients(52%) nontraumatic amputation 8 patients(24%) Group NO HT:DM 8 patients(24%) nontraumatic amputation 2 patients(6%) (TABLE 1) Conclusions: Until the actuality there is no optimal criteria of BP in hemodialysis patients, or when it should be measured pre or postdialysis. In our study, we do not see a difference between BP Predialysis, Postdialysis or Interdialytic BP. Also we see in group HT, there are more diabetics and more nontrauamtic amputation but there is no significant difference between both groups, possibly for being a small sample

Association of peridialytic, intradialytic, scheduled interdialytic and ambulatory BP recordings with cardiovascular events in hemodialysis patients.

Ambulatory-BP-monitoring (ABPM) is recommended for hypertension diagnosis and management in hemodialysispatients due toits strong association with outcomes. Intradialytic and scheduled interdialytic BP recordings show agreement with ambulatory BP. This study assesses in parallel the association of pre-dialysis, intradialytic, scheduled interdialytic and ambulatory BP recordings with cardiovascular events. We prospectively followed 242 hemodialysis patients with valid 48-h ABPMs for a median of 45.7months to examine the association of pre-dialysis, intradialytic, intradialytic plus pre/post-dialysis readings, scheduled interdialytic BP, and 44-h ambulatory BP with outcomes. The primary end-point was a composite one, composed of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, hospitalization for heart failure, coronary revascularization procedure or peripheral revascularization procedure. Cumulative freedom from the primary end-point was significantly lower with increasing 44-h SBP (group 1, < 120mmHg, 64.2%; group 2, ≥ 120 to < 130mmHg 60.4%, group 3, ≥ 130 to < 140mmHg 45.3%; group 4, ≥ 140mmHg 45.5%; logrank-p = 0.016). Similar were the results for intradialytic (logrank-p = 0.039), intradialytic plus pre/post-dialysis (logrank-p = 0.044), and scheduled interdialytic SBP (logrank-p = 0.030), but not for pre-dialysis SBP (logrank-p = 0.570). Consideringgroup 1 as the reference group, the hazard ratios of the primary end-point showed a gradual increase with higher BP levels with all BP metrics, except pre-dialysis SBP. This pattern was confirmedin adjusted analyses. An inverse association of DBP levels with outcomes was shown with all BP metrics, which was no longer evident in adjusted analyses. Averaged intradialytic and scheduled home BP measurements (but not pre-dialysis readings) display similar prognostic associations with 44-h ambulatory BP in hemodialysis patients and represent valid metrics for hypertension management in these individuals.

Timing of Antihypertensive Medications on Key Outcomes in Hemodialysis: A Cluster Randomized Trial.

We conducted this study to examine the effect of taking versus holding BP medications before hemodialysis on intradialytic hypotension (IDH). In this cluster randomized trial, each dialysis unit was randomly designated as TAKE or HOLD units. Participants within a TAKE unit were instructed to take all BP medications as prescribed, whereas participants within a HOLD unit were instructed to hold medications dosed more than once daily before hemodialysis. The intervention lasted for 4 weeks. We hypothesized that TAKE would be noninferior to HOLD on the primary outcome of asymptomatic IDH, defined as ≥30% of sessions with nadir systolic BP <90 mm Hg and on the following secondary outcomes: uncontrolled hypertension (predialysis systolic BP >160 mm Hg), failure to achieve dry weight, and shortened dialysis sessions. We randomized 10 dialysis units in a 1:1 ratio to TAKE or HOLD, which included 65 participants in TAKE and 66 participants in HOLD. We did not show that TAKE was noninferior to HOLD for the primary IDH outcome (mean unadjusted difference of 8%; 95% CI, -3% to 19%). TAKE was superior to HOLD for the outcome of uncontrolled hypertension (mean unadjusted difference of -15%, 95% CI, -28% to -1%). TAKE was noninferior to HOLD for the outcomes of failure to achieve dry weight and shortened dialysis sessions. In this cluster randomized trial that randomized patients to either taking or holding BP medications before hemodialysis, a strategy of taking BP medications dosed more than once daily was not noninferior to holding BP medications for the primary outcome of IDH, but did reduce the occurrence of uncontrolled hypertension. Whether any potential benefit of holding BP medications on reducing IDH is offset by any potential harm related to higher predialysis BP remains to be seen.

Intradialytic BP variability is associated with cardiovascular mortality and hospitalization in HD patients.

Studies showed that pre-dialysis BP variability (BPV) was an independent risk factor of cardiovascular disease (CVD) among HD patients, but which is limited on how intradialytic BPV affects prognosis. In this study, we designed a retrospective cohort study to examine the association between intradialytic BPV and CVD outcomes in HD patients. A total of 202 patients who underwent HD in our center were included, and all intradialytic BP measurements of November 2017 were obtained from the database. Patients were divided into four groups according to variability independent of the mean (VIM) interquartile. The mean age was 62.1 ± 14.3 years, 60.9% were male, and median VIM was 14.75 (12.60-18.59). Multiple-regression analyses showed patients age, dialysis vintage, serum albumin, and the percentage of intradialytic weight gain as significant predictors of VIM (all p values were <0.05). Kaplan-Meier survival curves showed that CVD mortality was greater in patients with higher VIM (p=0.05), whereas all-cause mortality had no significant difference between the four groups overall (p=0.149). Furthermore, multivariate regression analyses demonstrated that VIM (HR=1.091, p < 0.004) and age (HR=1.059, p=0.003) were significant independent predictors for CVD death. Logistic-regression models revealed that higher VIM groups were more likely to have CVD-related hospitalization (OR=1.085, p=0.030), whereas the association between VIM and all-cause hospitalization was not statistically significant (OR=1.015, p=0.669). This retrospective study suggested that higher intradialytic BPV was associated with increasing age, longer dialysis vintage, lower albumin, and greater ultrafiltration; intradialytic BPV could be an effective predictor for CVD mortality and hospitalization in the HD population.

MO843PREVALENCE AND MANAGEMENT OF HYPERTENSION IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Hypertension (HTN) is common in hemodialysis (HD) patients &amp; diagnosed by pre-dialysis BP &amp;gt;140/90 mmHg. Causes include high salt intake, volume overload, &amp; loss of residual kidney function. Therapy includes achieving correct dry weight with each session, restricting interdialytic sodium &amp; fluid intake &amp; medications. We review its prevalence, factors associated with it &amp; its management in our patients. Method Demographics, HD prescription &amp; medications data collected for patients from 5 dialysis centers. Results A total of 1585 files reviewed. Males were 51.8% &amp; mean age was 59. Mean age significantly higher for females (61 vs 57). ESKD cause was DM in 51% &amp; HTN in 35%. However, of files reviewed, adequate data on comorbidities in 1390 patients (table 1), 69% had DM, 92% had HTN, 47% had CVD &amp; 31% had BMI &amp;gt; 25 (which was significantly more frequent in females). HTN was more likely in older patients, diabetics &amp; females with odds of HTN in females nearly twice the odds of HTN in males &amp; odds of HTN with DM is 2.27 times odds of HTN without DM &amp; one-year increase in age would increase odds of HTN by nearly 4%. Mean pre-HD BP for those with HTN was 143/76 mmHg &amp; for those without HTN was 136/75 mmHg. HD frequency was thrice weekly in 94% &amp; HD duration was &amp;gt; 3.5 hours in only 77% of patients. HDF used in 81.5%. Mean interdialytic weight gain (IDWG) was 2.8 kg, with no difference according to gender or presence of DM or HTN (Table 2). Higher IDWG associated with age &amp;lt; 65, Calcium bath of 1.75 &amp; Sodium bath &amp;gt; 138 with 0.638 kg higher IDWG with calcium of 1.75 compared to calcium of 1.25. Higher IDWG was associated with higher BP. Mean volume of fluid removed per session was 2.74, which was less than mean IDWG, with no difference according to gender or DM, however, it was higher in the higher dialysate sodium group, &amp; lower in the shorter session group (with trend towards statistical significance). CCB used to treat HTN in 62% followed by βB in 52%. Number of patients with HTN on 1 drug 21%, 2 drugs 27%, 3 drugs 23%, ≥ 4 drugs 20% &amp; 9% missing data. Number of antihypertensives did not correlate with IDWG. Conclusion Interdialytic weight gain in our HD patients is excessive &amp; contributing to HTN. Patients must restrict salt &amp; fluid intake &amp; dialysis centers must regularly &amp; frequently assess dry weight, ensure thrice weekly schedule &amp; 4 hours per session are met, so excess fluid is completely removed. Also, high sodium &amp; high calcium baths need to be avoided.

MO103PREDICTION OF CARDIOVASCULAR OUTCOMES WITH PERIDIALYTIC, INTRADIALYTIC, SCHEDULED INTERDIALYTIC AND AMBULATORY BP RECORDINGS IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Ambulatory-BP-monitoring (ABPM) is recommended for hypertension diagnosis and management in hemodialysis subjects due to high accuracy and strong associations with outcomes. The agreement and prediction of averaged intradialytic BP readings and home BP readings with ABPM and clinical outcomes is not known. This study assesses in parallel the association of pre-dialysis, intradialytic, scheduled interdialytic and ambulatory BP recordings with cardiovascular outcomes and mortality in this population. Method We prospectively followed for 49.1±25.6 months 242 hemodialysis patients with valid 48-hour ABPMs to examine the association of pre-dialysis, intradialytic, intradialytic plus pre/post-dialysis readings, scheduled interdialytic BP (the average of out-of-dialysis day readings at 8:00 am and 8:00 pm) and 44-hour ambulatory BP with outcomes. The primary end-point was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, hospitalization for heart failure, coronary revascularization procedure or peripheral revascularization procedure. Results Cumulative freedom from the primary end-point was significantly lower with increasing 44-hour SBP (group 1, &amp;lt;120 mmHg, 64.2%; group 2, ≥120 to &amp;lt;130 mmHg 60.4%, group 3, ≥130 to &amp;lt;140 mmHg 45.3%; group 4, ≥140 mmHg 45.5%; logrank-p=0.016). Similar were the results for intradialytic (logrank-p=0.039), intradialytic plus pre/post-dialysis (logrank-p=0.044), and scheduled interdialytic SBP (logrank-p=0.030), but not for pre-dialysis SBP (logrank-p=0.570). With group 1 as the reference group, the Hazard Ratios of the primary end-point showed a gradual increase with higher BP levels with all BP metrics, except pre-dialysis SBP. An inverse association of DBP levels with outcomes was shown with all BP metrics. Conclusion Averaged intradialytic and scheduled home BP measurements (but not pre-dialysis readings) display similar patterns of prognostic associations with 44-hour ambulatory BP in hemodialysis patients and represent valid metrics for hypertension management in these individuals.

Individualized dialysate sodium prescriptions using sodium gradients for high-risk hemodialysis patients lowered interdialytic weight gain and achieved target weights.

Large interdialytic weight gain (IDWG) is associated with increased morbidity and mortality in chronic hemodialysis patients. Over 50% of patients at our inner city tertiary academic center dialysis unit had IDWG and target weights (TW) above goal. We conducted an open-label nonrandomized study to explore the effects of an individualized dialysate sodium (DNa) prescription using Na gradients in patients at high risk for large IDWG. Thirty-three patients receiving chronic hemodialysis received individualized DNa prescriptions with a DNa bath of 0 to -2 meq/L below their serum Na level in the intervention group, while patients in the control group were prescribed the standard dialysate Na at 138 mmol/L. Serum Na level, predialysis SBP, symptomatic hypotensive episodes, and %hemodialysis treatments with large IDWG (%TxAIDWG) and above TW(%TxATW) were recorded before and three months after the intervention. We used student t tests to compare continuous variables and Chi-square tests to compare binary variables between the groups at baseline and after the intervention. Age- and sex-adjusted linear regression models were also constructed to assess the differences in each continuous outcome between the groups. Multivariable logistic regression models were conducted by modeling IDWG decrease and above estimated-dry-weight (EDW) decrease as binary dependent variables with adjustment for age, sex, and EDW change. Patients with individualized DNa concentrations had 3.6 times greater odds of having lower IDWG than those with standard dialysate Na concentration. This significant association remained after adjustment for age, sex, and changes in EDW (OR: 3.63; 95% CI, 1.03-12.9). There was no difference in predialysis BP or symptomatic hypotensive episodes between the two groups. Individualized DNa prescriptions appeared to be well tolerated and may be effective for optimal fluid management in high-risk hemodialysis patients.

Increased Weight Gain During the Long Interdialytic Period Is Associated with Minor Effects on Blood Pressure Control in Clinically Stable In-Centre Haemodialysis Patients

Background/Aims: Three-day-a-week chronic haemodialysis (cHD) involves 1 long (72 h) and 2 short (48 h) inter-dialytic periods (IDPs). We aimed to determine whether BP control following the long IDP is inferior to the short IDPs. Methods: All pre- and post-dialysis BP and weight measurements over a 4-week period were retrospectively analyzed among 135 clinically stable cHD patients at 2 academic centres with comparisons between measurements recorded following short and long IDPs. Subsequently, 23 clinically stable cHD patients underwent 24-h ambulatory blood pressure monitoring (ABPM) during the final day/night cycle of the long IDP and 1 short IDP within the same week. Results: In combined and separate analyses of the 2 retrospective cohorts, pre-dialysis BP parameters were not different following long and short IDPs despite greater inter-dialytic weight gain (IDWG) during the long IDP. Subgroup analyses of the total cohort showed no evidence for inferior BP control during the long IDP among those with high %IDWG. In the ABPM study, nocturnal hypertension and loss of nocturnal dipping were frequent. Furthermore, daytime systolic blood pressure (SBP) and pulse pressure were modestly higher during the last day/night cycle of the long compared with short IDP. Conclusion: In stable cHD patients, the greater IDWG that occurred during the long IDP was not associated with overtly inferior BP control as reflected in pre-dialysis BP measurements. However, modestly higher daytime SBP was evident towards the end of the long IDP by 24 h ABPM. Thus, while fluid gain has well-documented associations with hypertension and adverse cardiovascular outcomes, the excess IDWG that occurs during the long IDP exerts relatively minor effects on BP control in patients on well-established dialysis regimens that are better identified by ambulatory monitoring.

The association of interdialytic blood pressure variability with cardiovascular events and all-cause mortality in haemodialysis patients.

Long-term pre-dialysis blood pressure variability (BPV) in haemodialysis patients is associated with increased cardiovascular risk. The association of the main haemodynamic culprit in dialysis, that is, short-term BPV, with outcomes has not been investigated. We examine the prognostic role of short-term BPV for mortality and cardiovascular events in this population. A total of 227 haemodialysis patients underwent 44-h ambulatory monitoring during a standard interval and were followed-up for 30.17 ± 17.70 months. We calculated SD, weighted SD (wSD), coefficient of variation (CV) and average real variability (ARV) of BP with validated formulas. The primary endpoint was first occurrence of all-cause death, non-fatal myocardial infarction or non-fatal stroke. Secondary endpoints were: (i) all-cause mortality, (ii) cardiovascular mortality and (iii) a combination of cardiovascular events. Cumulative freedom from the primary endpoint was similar for quartiles of pre-dialysis and 44-h systolic BP (SBP), but was progressively longer for increasing quartiles of 44-h SBP-SD (P = 0.014), wSD (P = 0.007), CV (P = 0.031) and ARV (83.9, 71.9, 70.2 and 43.9% for quartiles 1-4; P < 0.001). Higher quartiles of 44-h SBP-ARV were associated with higher risk of all studied outcomes. Among diastolic BPV indices, 44-h diastolic BP (DBP)-CV and 44-h DBP-ARV were associated with increased risk for the composite cardiovascular outcome. In Cox regression analysis, SBP-BPV was related to the primary endpoint, independently of SBP levels and interdialytic weight gain [ARV: hazard ratio (HR) 1.115, 95% confidence interval (95% CI) 1.048-1.185]. This association become insignificant after adjustment for pulse wave velocity (PWV; HR 1.061, 95% CI 0.989-1.137), and further attenuated after additional adjustment for age, dialysis vintage, gender, comorbidities and prevalent cardiovascular disease (HR 1.031, 95% CI 0.946-1.122). Increased BPV during the interdialytic interval is associated with higher risk of death and cardiovascular events, whereas ambulatory BP levels are not. This association was not independent after adjustment for PWV, other risk factors and prevalent cardiovascular disease. Short-term BPV could be a mediator promoting the adverse cardiovascular profile of haemodialysis patients.

Chronic Fluid Overload and Mortality in ESRD.

Sustained fluid overload (FO) is considered a major cause of hypertension, heart failure, and mortality in patients with ESRD on maintenance hemodialysis. However, there has not been a cohort study investigating the relationship between chronic exposure to FO and mortality in this population. We studied the relationship of baseline and cumulative FO exposure over 1 year with mortality in 39,566 patients with incident ESRD in a large dialysis network in 26 countries using whole-body bioimpedance spectroscopy to assess fluid status. Analyses were applied across three discrete systolic BP (syst-BP) categories (<130, 130-160, and >160 mmHg), with nonoverhydrated patients with syst-BP=130-160 mmHg as the reference category; >200,000 FO measurements were performed over follow-up. Baseline FO value predicted excess risk of mortality across syst-BP categories (<130 mmHg: hazard ratio [HR], 1.51; 95% confidence interval [95% CI], 1.38 to 1.65; 130-160 mmHg: HR, 1.25; 95% CI, 1.16 to 1.36; >160 mmHg: HR, 1.30; 95% CI, 1.19 to 1.42; all P<0.001). However, cumulative 1-year FO exposure predicted a higher death risk (P<0.001) across all syst-BP categories (<130 mmHg: HR, 1.94; 95% CI, 1.68 to 2.23; 130-160 mmHg: HR, 1.51; 95% CI, 1.35 to 1.69; >160 mmHg: HR, 1.62; 95% CI, 1.39 to 1.90). In conclusion, chronic exposure to FO in ESRD is a strong risk factor for death across discrete BP categories. Whether treatment policies that account for fluid status monitoring are preferable to policies that account solely for predialysis BP measurements remains to be tested in a clinical trial.

Association of mortality risk with various definitions of intradialytic hypotension.

Intradialytic hypotension is a serious and frequent complication of hemodialysis; however, there is no evidence-based consensus definition of intradialytic hypotension. As a result, coherent evaluation of the effects of intradialytic hypotension is difficult. We analyzed data from 1409 patients in the HEMO Study and 10,392 patients from a single large dialysis organization to investigate the associations of commonly used intradialytic hypotension definitions and mortality. Intradialytic hypotension definitions were selected a priori on the basis of literature review. For each definition, patients were characterized as having intradialytic hypotension if they met the corresponding definition in at least 30% of baseline exposure period treatments or characterized as control otherwise. Overall and within subgroups of patients with predialysis systolic BP<120 or 120-159 mmHg, an absolute nadir systolic BP<90 mmHg was most potently associated with mortality. Within the subgroup of patients with predialysis BP≥160 mmHg, nadir BP<100 mmHg was most potently associated with mortality. Intradialytic hypotension definitions that considered symptoms, interventions, and decreases in BP during dialysis were not associated with outcome, and when added to nadir BP, symptom and intervention criteria did not accentuate associations with mortality. Our results suggest that nadir-based definitions best capture the association between intradialytic hypotension and mortality.

Preservation of residual renal function by not removing water in new hemodialysis patients: a randomized, controlled study

To investigate the effect of no water removal (NWR) on preservation of residual renal function (RRF) in new hemodialysis (HD) patients. Fifty-six patients with a daily urine volume ≥ 1,000 mL were included. Patients were randomized to different fluid management groups of NWR or water removal (WR) for 6 months. If predialysis BP was >150/90 mmHg, patients could take antihypertensive drugs. The primary endpoints included death, cardio-cerebral vascular disease, refractory hypertension, and edema or an auxiliary examination indicating obvious fluid retention. The secondary endpoint was oliguria. A daily urine volume, 24-h urine creatinine clearance, the defined daily dose (DDD) index of antihypertensive drugs, erythropoietin resistance index, cardiothoracic ratio, and left ventricular mass index (LVMI) were recorded. Eight patients in the NWR group reached the primary endpoints. Nine patients in the WR group reached the secondary endpoint. At the end of the study, patients in the NWR group had more increased systemic blood pressure (9.0 ± 8.3 vs. -2.4 ± 2.0 mmHg, p < 0.001), DDD index (1.2 ± 1.02 vs. -0.9 ± 0.51, p < 0.001), daily urine volume (164 ± 351 vs. -726 ± 342 mL, p < 0.001), cardiothoracic ratio (0.02 ± 0.04 vs. -0.03 ± 0.03, p < 0.001), LVMI (9.6 ± 17.0 vs. -12.0 ± 21.4 g/m(2), p < 0.001), and less decreased urine creatinine clearance (-1.0 ± 0.4 vs. -2.0 ± 1.0, p < 0.001), compared with those patients in the WR group. Preservation of RRF by NWR is warranted in new HD patients, but is not appropriate for all patients.

Intradialytic Hypotension Strikes Again

Intradialytic hypotension (IDH) has plagued hemodialysis (HD) patients and their caregivers since the early days of renal replacement therapy. Its persistence in the current era is evident from the results of the 1426-patient Hemodialysis (HEMO) study in this issue of JASN in which a median of 12.5

Toward a Definition of Masked Hypertension and White-Coat Hypertension among Hemodialysis Patients

Among people with essential hypertension, ambulatory BP measurement is superior to BP obtained in the clinic in predicting cardiovascular outcomes. In part, this is because it can detect white-coat hypertension and masked hypertension. Whether the same is true for hemodialysis patients is not known. Using a threshold of 140/80 mmHg for median midweek dialysis-unit BP and 135/85 mmHg for 44-hour ambulatory BP, we defined four categories of BP: sustained normotension (SN), white-coat hypertension (WCH), masked hypertension (MHTN), and sustained hypertension (SHTN). Among 355 long-term hemodialysis patients, the prevalence of SN was 35%, WCH 15%, MHTN 15%, and SHTN 35%. Over a mean follow-up of 29.6 (SD 21.7) months, 102 patients died (29%), yielding a crude mortality rate of 121/1000 patient-years. Unadjusted and multivariate-adjusted analyses showed increasing all-cause mortality with increasing severity of hypertension (unadjusted hazard ratios from SN, WCH, MHTN, SHTN: 1, 1.12, 1.70, 1.80, respectively [P for trend < 0.01]; adjusted hazard ratios: 1, 1.30, 1.36, 1.87, respectively [P for trend 0.02]). When a predialysis BP threshold of 140/90 mmHg was used to classify patients into BP categories, the prevalence of SN was 24%, WCH 26%, MHTN 4%, and SHTN 47%. Hazard ratios for mortality were similar when compared with median midweek dialysis-unit BP. As in the essential hypertension population, MHTN and WCH have prognostic significance. The prognostic value of BP obtained in the dialysis unit can be refined with ambulatory BP monitoring.

Blood Pressure and Mortality among ESRD Patients

The annual risk for mortality is extremely high for patients who have ESRD and are treated with dialysis in the United States,1 and cardiovascular disease persists as their most common cause of death.2 Hypertension affects the majority of hemodialysis patients, and most have what would be considered uncontrolled hypertension.3 However, appropriate BP targets for these patients remain uncertain and have largely been extrapolated from studies conducted of the general population. The Kidney Disease Outcomes Quality Initiative (KDOQI) Work Group on this subject offered an opinion of “a reasonable goal is predialysis BP <140/90 mmHg,” but the evidence to support their statement was reported as weak.4 The weakness of this conclusion stems partly from the exclusion of patients with ESRD from randomized trials involving antihypertensive drugs and BP targets, thereby leaving nephrologists to rely on observational data for guidance on the best approach to manage BP in dialysis patients. Adding to the problem, these epidemiologic data are not always in agreement in their reported relationship between BP and mortality, and their findings vary on a number of factors, including when BP was analyzed (before versus after dialysis), whether early (1 to 2 years) versus late (>3 years) mortality was assessed, and whether pulse pressure …

Determinants of Left Ventricular Mass and Hypertrophy in Hemodialysis Patients Assessed by Cardiac Magnetic Resonance Imaging

Left ventricular hypertrophy (LVH) is an independent risk factor for premature cardiovascular death in hemodialysis (HD) patients and one of the three forms of uremic cardiomyopathy. Cardiovascular magnetic resonance (CMR) is a volume-independent technique to assess cardiac structure. We used CMR to assess the determinants of left ventricular mass (LVM) and LVH in HD patients. A total of 246 HD patients (63.8% male; mean age 51.5 +/- 12.1 yr) underwent CMR on a postdialysis day. LVM was measured from a stack of cine loops and indexed for body surface area (LVM index [LVMI]). Demographic, past biochemical, hematologic, and dialysis data were collected by patient record review. Results up to 180 d before CMR were collected. LVH was defined as LVMI >84.1 g/m(2) (male) or >76.4 g/m(2) (female). A total of 157 (63.8%) patients had LVH. LVH was more common in patients with higher predialysis systolic BP, predialysis pulse pressure, and calcium-phosphate product (Ca X PO4). Furthermore, LVH was significantly associated with higher end-diastolic and systolic volumes and lower ejection fraction. There were positive correlations with LVMI and end-diastolic and systolic volumes. There were weak positive correlations among LVMI, mean volume of ultrafiltration, and Ca X PO4. Using multivariate linear and logistic regression (entering one BP and cardiac variable), the independent predictors of LVMI and LVH were end-diastolic volume, predialysis systolic BP, and Ca X PO4. The principal determinants of LVM and LVH in HD patients are end-diastolic LV volume, predialysis BP, and Ca X PO4.

Ten Years Experience of In-Center Thrice Weekly Long Overnight Hemodialysis

Published studies suggest that longer hemodialysis (HD) sessions are associated with improved morbidity and mortality, but few centers offer long sessions. The Western Infirmary renal unit has offered long overnight hemodialysis (LOH) (6 to 7 h) thrice weekly since 1998. The aim of this study was to describe patients who chose LOH and compare outcomes with patients on conventional hours (4 to 5 h) HD. Patients who ever had LOH for three or more consecutive sessions were identified (n = 146). Indices of urea reduction ratio (URR), anemia, hyperphosphatemia, and predialysis BP (BP) control in a subgroup of all patients on LOH for at least 1 yr since 2004 were compared with age, sex, and diabetes-matched controls undergoing conventional duration HD. The mean age at the time of starting LOH was 51.8 yr and 74.7% started with a functioning arteriovenous fistula. Median duration of continuous LOH was 1.6 yr. Of those no longer on LOH, only 33.3% reverted to conventional hours HD (mean duration LOH 2.2 yr). When comparing LOH and conventional HD cohorts, there was increased URR and mean hemoglobin with a trend toward lower mean erythropoietin index. There was a trend toward fewer phosphate binder tablets but no difference in mean serum phosphate, BP, or number of prescribed antihypertensive medicines. LOH is a well tolerated hemodialysis option, associated with improved URR and better control of anemia.