Lung Ultrasound-Guided Dry-Weight Reduction in Hemodialysis Patients Does Not Affect Short-Term Blood Pressure Variability

Kidney transplantation and kidney donation do not affect short-term blood pressure variability

PURPOSE

Blood pressure variability (BPV) is an independent cardiovascular risk factor in CKD. Kidney transplantation (KTx) is associated with improved BP levels for kidney transplant recipient (KTRs), without evoking significant changes in donors. The aim of this study was to assess the short- and mid-time effects of KTx and donation on short-term BPV in KTRs and their respective living kidney donors.

MATERIALS AND METHODS

Forty KTRs and their respective donors were evaluated with 24-h ABPM (Mobil-O-Graph-NG) at baseline (1 month before), 3-months and 12-months after KTx. Standard-deviation (SD), weighted-SD (wSD), coefficient-of-variation (CV), average-real-variability (ARV) and variability independent of mean (VIM) for SBP/DBP were calculated with validated formulas.

RESULTS

All 24-h systolic and diastolic BPV indexes studied did not change significantly from baseline to 3-month (SBP-wSD: 12.8 ± 3.0 vs 13.2 ± 3.4 mmHg, p = 0.608; SBP-ARV: 10.3 ± 2.4 vs 10.8 ± 2.6 mmHg, p = 0.463) and 12-month evaluation (SBP-wSD 12.8 ± 3.0 vs 12.1 ± 2.8; p = 0.424 and SBP-ARV: 10.3 ± 2.4 vs 10.2 ± 2.5; p = 0.615) after kidney transplantation in the KTRs.In kidney donors, all 24-h systolic BPV indices displayed a trend towards higher values at 3 months compared to baseline, but without reaching statistical significance (SBP-wSD: 12.2 ± 2.8 vs 13.6 ± 4.2 mmHg, p = 0.107 and SBP-ARV: 10.1 ± 2.1 vs 11.2 ± 3.1 mmHg, p = 0.099), the levels of 24-h systolic SBP indices at 12-months were almost identical to baseline values. 24-h diastolic BPV indices at 3-month and 12-month evaluation were similar to baseline.

CONCLUSION

Short-term BPV did not change significantly 3 and 12 months after kidney transplantation/donation neither in KTRs nor in living kidney donors. Longitudinal studies examining associations of BPV with adverse outcomes in these individuals are needed.

Blood pressure variability: methodological aspects, clinical relevance and practical indications for management - a European Society of Hypertension position paper ∗

Blood pressure is not a static parameter, but rather undergoes continuous fluctuations over time, as a result of the interaction between environmental and behavioural factors on one side and intrinsic cardiovascular regulatory mechanisms on the other side. Increased blood pressure variability (BPV) may indicate an impaired cardiovascular regulation and may represent a cardiovascular risk factor itself, having been associated with increased all-cause and cardiovascular mortality, stroke, coronary artery disease, heart failure, end-stage renal disease, and dementia incidence. Nonetheless, BPV was considered only a research issue in previous hypertension management guidelines, because the available evidence on its clinical relevance presents several gaps and is based on heterogeneous studies with limited standardization of methods for BPV assessment. The aim of this position paper, with contributions from members of the European Society of Hypertension Working Group on Blood Pressure Monitoring and Cardiovascular Variability and from a number of international experts, is to summarize the available evidence in the field of BPV assessment methodology and clinical applications and to provide practical indications on how to measure and interpret BPV in research and clinical settings based on currently available data. Pending issues and clinical and methodological recommendations supported by available evidence are also reported. The information provided by this paper should contribute to a better standardization of future studies on BPV, but should also provide clinicians with some indications on how BPV can be managed based on currently available data.

Sex-related short-term blood pressure variability differences in kidney transplant recipients

OBJECTIVE

Kidney transplant recipients (KTRs) display higher cardiovascular morbidity and mortality than the general population. Increased short-term blood pressure variability (BPV) is associated with a higher risk of adverse cardiovascular outcomes in chronic kidney disease (CKD). The aim of this study is to investigate sex differences in short-term BPV in KTRs.

METHODS

In total, 136 male and 69 female KTRs with valid 24 h ambulatory blood pressure monitoring were included in this analysis. Systolic and diastolic BPV indices [SD, weighted SD (wSD), coefficient of variation (CV), average real variability (ARV) and variability independent of the mean (VIM)] were calculated with validated formulas for the 24 h, daytime and nighttime periods.

RESULTS

Age, time from transplantation surgery and history of major comorbidities did not differ between men and women. During the 24-h period, systolic BPV indices did not differ between men and women (SBP-ARV: 9.4 ± 2.2 vs. 9.9 ± 2.5; P = 0.212). During the daytime period, SBP-CV and SBP-VIM were significantly higher in females compared with male participants (SBP-CV: 9.9 ± 2.4 vs. 11 ± 3.1%; P = 0.022 and SBP-VIM: 12.6 ± 3.0 vs 14.2 ± 3.9; P = 0.008); daytime SBP-SD and SBP-ARV, and all studied indexes during nighttime did not differ between groups. No significant between-group differences in 24 h and daytime diastolic BPV indices were detected. Nighttime DBP-CV was marginally higher in men (12.0 ± 3.6 vs. 11.4 ± 4.0; P = 0.053); the rest nighttime diastolic BPV indices measured were also nonsignificantly higher in men.

CONCLUSION

In conclusion, 24-h systolic and diastolic BPV parameters did not differ between male and female KTRs, but short-term BPV over the respective day- and nighttime periods showed different trends in men and women. Further studies are needed to examine possible differences in long-term BPV in KTRs.

Long-term predialysis blood pressure variability and outcomes in hemodialysis patients

Blood pressure variability (BPV) is significantly associated with cardiovascular diseases (CVD) and mortality in hemodialysis patients. However, the relationship between blood pressure and CVD in hemodialysis patients is complex and affected by many factors. The present study aimed to assess the association of long‐term predialysis BPV with all‐cause mortality and major adverse cardiovascular events (MACE). One thousand seven hundred twenty‐seven patients receiving maintenance hemodialysis were recruited in nine hemodialysis centers. Predialysis BPV was assessed over 1‐year intervals. Outcomes included all‐cause mortality and MACE during follow‐up periods. The mean age of the final cohort was 59 years, of which 57% were males. Greater predialysis systolic BPV was associated with an increased risk of all‐cause mortality (adjusted hazard ratio, 1.101; 95% confidence intervals 1.064–1.140) and MACE (adjusted hazard ratio, 1.091; 95% confidence intervals 1.059–1.125). Results were similar when systolic BPV was stratified by baseline systolic blood pressure. In conclusion, greater predialysis BPV among hemodialysis patients was associated with all‐cause mortality and MACE. Strategies to reduce blood pressure variability might be beneficial for hemodialysis patients.

Lung ultrasound guided dry-weight reduction and echocardiographic changes in clinically euvolemic hypertensive hemodialysis patients: 12-month results of a randomized controlled trial

BACKGROUND

Left ventricular hypertrophy (LVH) and dysfunction are highly prevalent in hemodialysis patients and independently associated with adverse outcomes. This study examines the long-term effects of dry-weight reduction with a standardized lung-ultrasound (US)-guided strategy on echocardiographic indexes of left ventricular (LV) mass and function in hemodialysis patients.

METHODS

Seventy-one clinically euvolemic, hemodialysis patients with hypertension were randomized to dry-weight reduction guided by pre-hemodialysis lung US (n=35) or standard-of-care treatment (n=36) and were followed-up for 12 months. Two-dimensional and tissue-Doppler echocardiography (TDI) were performed at baseline and study-end.

RESULTS

During follow-up, dry-weight reduction took place in more patients in the active than in the control arm of the trial (71.4% vs 22.2%; p<0.001). Left atrial (LA) surface (-1.37±4.50 vs 1.28±5.00 cm²; P=0.006) and LA volume index (-3.22±11.82 vs 4.76±12.83 ml/m²; P=0.009) decreased in the active and increased in the control group. LV end-diastolic volume (-0.94±11.45 vs 6.58±13.92 ml/m²; P=0.015) decreased only in the active group. LV mass index was unchanged in the active (134.21±44.75 vs 133.57±45.51; P=0.844) and marginally increased in the control group (134.21±40.96 vs 143.77±50.04 g/m²; P=0.089). LV E/e' wave ratio was unchanged in the active (12.45±4.69 vs 12.56±4.89; P=0.521) and increased in the usual-care group (10.91±4.97 vs12.36±6.43; P=0.003). LV systolic function did not differ among the two study arms across the trial.

CONCLUSIONS

Over 12 months, lung-US-guided dry-weight reduction is associated with reverse LV and LA remodeling, myocardial hypertrophy regression and improved LV diastolic filling properties.

Ambulatory blood pressure changes with lung ultrasound-guided dry-weight reduction in hypertensive hemodialysis patients: 12-month results of a randomized controlled trial

OBJECTIVES

Hypertension is highly prevalent and independently associated with adverse outcomes in patients undergoing hemodialysis. Volume overload is the main mechanism of increased blood pressure (BP) in these individuals. This study examines the long-term effects of dry-weight reduction with a standardized lung-ultrasound (US)-guided strategy on ambulatory BP in hypertensive hemodialysis patients.

METHODS

This is the report of the 12-month follow-up of a randomized controlled trial in 71 clinically euvolemic, hemodialysis patients with hypertension. Patients were randomized to dry-weight reduction guided by prehemodialysis lung ultrasound and to standard care. A 48-h ambulatory BP monitoring (ABPM) was performed in all study participants at baseline and after 12 months.

RESULTS

During follow-up, a greater proportion of patients in the active group underwent dry-weight reduction compared with the control group (71.4% vs. 22.2%; P < 0.001). The number of lung US-B lines (a metric of lung water) reduced in the active (-4.83 ± 13.73) and increased in the control arm (+5.53 ± 16.01; P = 0.005) paralleling dry-weight changes (-1.68 ± 2.38 vs. 0.54 ± 2.32 kg; P < 0.001). At 12 months, 48-h systolic BP (136.19 ± 14.78 vs. 130.31 ± 13.57 mmHg; P = 0.034) and diastolic BP (80.72 ± 9.83 vs. 76.82 ± 8.97 mmHg; P = 0.008) were lower compared to baseline in the active but similar in the control group. Changes in 48-h systolic BP (-7.78 ± 13.29 vs. -0.10 ± 14.75 mmHg; P = 0.021) were significantly greater in the active compared to the control group. The proportion of patients experiencing ≥1 episode of intradialytic hypotension was nominally lower in the active group (71.4% vs. 88.9%, P = 0.065).

CONCLUSIONS

Lung-US-guided dry-weight reduction can effectively and safely decrease ambulatory BP levels in the long-term.

Dapagliflozin Does Not Affect Short-Term Blood Pressure Variability in Patients With Type 2 Diabetes Mellitus

BACKGROUND

Increased blood pressure variability (BPV) is associated with increased cardiovascular and all-cause mortality in patients with type-2 diabetes mellitus (T2DM). Sodium-glucose co-transporter 2 (SGLT-2) inhibitors decrease the incidence of cardiovascular events, renal events, and death in this population. This study aimed to evaluate the effect of dapagliflozin on short-term BPV in patients with T2DM.

METHODS

This is a secondary analysis of a double-blind, randomized, placebo-controlled trial in 85 patients with T2DM. Subjects were randomized to dapagliflozin 10 mg/day or placebo for 12 weeks. All participants underwent 24-hour ambulatory blood pressure (BP) monitoring with Mobil-O-Graph-NG device at baseline and study-end. SD, weighted SD (wSD), coefficient of variation, average real variability (ARV), and variation independent of mean were calculated for the 24-hour, daytime and nighttime periods.

RESULTS

Dapagliflozin reduced 24-hour brachial BP compared with placebo. From baseline to study-end 24-hour brachial BPV indexes did not change with dapagliflozin (SBP-ARV: 11.51 ± 3.45 vs. 11.05 ± 3.35; P = 0.326, SBP-wSD: 13.59 ± 3.60 vs. 13.48 ± 3.33; P = 0.811) or placebo (SBP-ARV: 11.47 ± 3.63 vs. 11.05 ± 3.00; P = 0.388, SBP-wSD: 13.85 ± 4.38 vs. 13.97 ± 3.87; P = 0.308). Similarly, no significant changes in BPV indexes for daytime and nighttime were observed in any group. At study-end, no between-group differences were observed for any BPV index. Deltas (Δ) of all indexes during follow-up were minimal and not different between groups (SBP-wSD: dapagliflozin: -0.11 ± 3.05 vs. placebo: 0.12 ± 4.20; P = 0.227).

CONCLUSIONS

This study is the first to evaluate the effects of an SGLT-2 inhibitor on short-term BPV in T2DM, showing no effect of dapagliflozin on all BPV indexes studied.

CLINICAL TRIALS REGISTRATION

Trial Number NCT02887677.

Volume overload in hemodialysis: diagnosis, cardiovascular consequences, and management

Volume overload in haemodialysis (HD) patients associates with hypertension and cardiac dysfunction and is a major risk factor for all-cause and cardiovascular mortality in this population. The diagnosis of volume excess and estimation of dry weight is based largely on clinical criteria and has a notoriously poor diagnostic accuracy. The search for accurate and objective methods to evaluate dry weight and to diagnose subclinical volume overload has been intensively pursued over the last 3 decades. Most methods have not been tested in appropriate clinical trials and their usefulness in clinical practice remains uncertain, except for bioimpedance spectroscopy and lung ultrasound (US). Bioimpedance spectroscopy is possibly the most widely used method to subjectively quantify fluid distributions over body compartments and produces reliable and reproducible results. Lung US provides reliable estimates of extravascular water in the lung, a critical parameter of the central circulation that in large part reflects the left ventricular end-diastolic pressure. To maximize cardiovascular tolerance, fluid removal in volume-expanded HD patients should be gradual and distributed over a sufficiently long time window. This review summarizes current knowledge about the diagnosis, prognosis and treatment of volume overload in HD patients.

Sodium, volume and pressure control in haemodialysis patients for improved cardiovascular outcomes

Chronic volume overload is pervasive in patients on chronic haemodialysis and substantially increases the risk of cardiovascular death. The rediscovery of the three-compartment model in sodium metabolism revolutionizes our understanding of sodium (patho-)physiology and is an effect modifier that still needs to be understood in the context of hypertension and end-stage kidney disease. Assessment of fluid overload in haemodialysis patients is central yet difficult to achieve, because traditional clinical signs of volume overload lack sensitivity and specificity. The highest all-cause mortality risk may be found in haemodialysis patients presenting with high fluid overload but low blood pressure before haemodialysis treatment. The second highest risk may be found in patients with both high blood pressure and fluid overload, while high blood pressure but normal fluid overload may only relate to moderate risk. Optimization of fluid overload in haemodialysis patients should be guided by combining the traditional clinical evaluation with objective measurements such as bioimpedance spectroscopy in assessing the risk of fluid overload. To overcome the tide of extracellular fluid, the concept of time-averaged fluid overload during the interdialytic period has been established and requires possible readjustment of a negative target post-dialysis weight. ²³Na-magnetic resonance imaging studies will help to quantitate sodium accumulation and keep prescribed haemodialytic sodium mass balance on the radar. Cluster-randomization trials (e.g. on sodium removal) are underway to improve our therapeutic approach to cardioprotective haemodialysis management.