The impact of exercising during haemodialysis on blood pressure, markers of cardiac injury and systemic inflammation - preliminary results of a pilot study

Background/Aims: Patients requiring haemodialysis have cardiovascular and immune dysfunction. Little is known about the acute effects of exercise during haemodialysis. Exercise has numerous health benefits but in other populations has a profound impact upon blood pressure, inflammation and immune function; therefore having the potential to exacerbate cardiovascular and immune dysfunction in this vulnerable population. Methods: Fifteen patients took part in a randomised-crossover study investigating the effect of a 30-min bout of exercise during haemodialysis compared to resting haemodialysis. We assessed blood pressure, plasma markers of cardiac injury and systemic inflammation and neutrophil degranulation. Results: Exercise increased blood pressure immediately post-exercise; however, 1 hour after exercise blood pressure was lower than resting levels (106±22 vs. 117±25 mm Hg). No differences in h-FABP, cTnI, myoglobin or CKMB were observed between trial arms. Exercise did not alter circulating concentrations of IL-6, TNF-α or IL-1ra nor clearly suppress neutrophil function. Conclusions: This study demonstrates fluctuations in blood pressure during haemodialysis in response to exercise. However, since the fall in blood pressure occurred without evidence of cardiac injury, we regard it as a normal response to exercise superimposed onto the haemodynamic response to haemodialysis. Importantly, exercise did not exacerbate systemic inflammation or immune dysfunction; intradialytic exercise was well tolerated

An increase in circulating monocyte and platelet derived microparticles during haemodialysis

An increase in circulating monocyte and platelet derived microparticles during haemodialysi

Regular exercise during haemodialysis promotes an anti-inflammatory leucocyte profile

Background Cardiovascular disease (CVD) is the most common cause of mortality in haemodialysis (HD) patients and is highly predicted by markers of chronic inflammation. Regular exercise may have beneficial anti-inflammatory effects, but this is unclear in HD patients. This study assessed the effect of regular intradialytic exercise on soluble inflammatory factors and inflammatory leukocyte phenotypes. Methods Twenty-two HD patients from a centre where intradialytic cycling was offered thrice-weekly and 16 HD patients receiving usual care volunteered. Exercising patients aimed to cycle for 30 min at RPE of “somewhat hard”. Baseline characteristic were compared with 16 healthy age-matched individuals. Physical function, soluble inflammatory markers and leukocyte phenotypes were assessed again after 6 months of regular exercise. Results Patients were less active than their healthy counterparts and had significant elevations in measures of inflammation (IL-6, CRP, TNF-α, intermediate and non-classical monocytes; all P<0.001). Six months of regular intradialytic exercise improved physical function (sit-to-stand 60). After 6 months the proportion of intermediate monocytes in the exercising patients reduced compared to non-exercisers (7.58±1.68 to 6.38±1.81% vs. 6.86±1.45 to 7.88±1.66%; P<0.01). Numbers (but not proportion) of regulatory T cells decreased in the non-exercising patients only (P<0.05). Training had no significant effect on circulating IL-6, CRP or TNF-α concentrations. Conclusions These findings suggest regular intradialytic exercise is associated with an anti-inflammatory effect at a circulating cellular level but not in circulating cytokines. This may be protective against the increased risk of CVD and mortality that is associated with chronic inflammation and elevated numbers of intermediate monocytes

Implementing a theory-based intradialytic exercise programme in practice: a quality improvement project

Background Research evidence outlines the benefits of intradialytic exercise (IDE), yet implementation into practice has been slow, ostensibly due to lack of patient and staff engagement. The aim of this quality improvement project was to improve patient outcomes via the introduction of an IDE programme; evaluate patient uptake, sustainability and enhance the engagement of routine haemodialysis (HD) staff with the delivery of the IDE programme. Methods We developed and refined an IDE programme, including interventions designed to increase patient and staff engagement that were based upon the Theoretical Domains Framework, using a series of ‘Plan, Do, Study, Act’ cycles. The programme was introduced at two UK NHS HD units. Process measures included patient uptake, withdrawals, adherence and HD staff involvement. Outcomes measures were patient-reported functional capacity, anxiety, depression and symptomology. All measures were collected over 12 months. Results 95 patients enrolled in the IDE programme. 64 (75%) were still participating at three months, dropping to 41 (48%) at 12 months. Adherence was high (78%) at three months, dropping to 63% by 12 months. Provision of IDE by HD staff accounted for a mean of 2 (5%) sessions per three-month time point. Patients displayed significant improvements in functional ability (p=0.01), and reduction in depression (p=0.02) over 12 months, but effects seen were limited to those who completed the programme. Conclusions A theory-based IDE programme is feasible and leads to improvement in functional capacity and depression. Sustaining IDE over time is marred by high levels of patient withdrawal from the programme. Significant change at an organisational level is required to enhance sustainability by increasing HD staff engagement or access to exercise professional support

A randomized controlled trial to investigate the effects of intra-dialytic cycling on left ventricular mass

Cardiovascular disease is the leading cause of death for patients receiving hemodialysis. Since exercise mitigates many risk factors which drive cardiovascular disease for these patients, we assessed effects of a program of intra-dialytic cycling on left ventricular mass and other prognostically relevant measures of cardiovascular disease as evaluated by cardiac MRI (the CYCLE-HD trial). This was a prospective, open-label, single-blinded cluster-randomized controlled trial powered to detect a 15g difference in left ventricular mass measured between patients undergoing a six-month program of intra-dialytic cycling (exercise group) and patients continuing usual care (control group). Pre-specified secondary outcomes included measures of myocardial fibrosis, aortic stiffness, physical functioning, quality of life and ventricular arrhythmias. Outcomes were analyzed as intention-to-treat according to a pre-specified statistical analysis plan. Initially, 130 individuals were recruited and completed baseline assessments (65 each group). Ultimately, 101 patients completed the trial protocol (50 control group and 51 exercise group). The six-month program of intra-dialytic cycling resulted in a significant reduction in left ventricular mass between groups (-11.1g; 95% confidence interval -15.79, -6.43), which remained significant on sensitivity analysis (missing data imputed) (-9.92g; 14.68, -5.16). There were significant reductions in both native T1 mapping and aortic pulse wave velocity between groups favoring the intervention. There was no increase in either ventricular ectopic beats or complex ventricular arrhythmias as a result of exercise with no significant effect on physical function or quality of life. Thus, a six-month program of intradialytic cycling reduces left ventricular mass and is safe, deliverable and well tolerated