Exercise and Vascular Parameters in Hemodialysis

Arterial calcification is very common in the incident hemodialysis population, ranging 71-83%.Given that cardiovascular disease is a major cause of mortality in the hemodialysis population, medial arterial calcification may contribute through increased risk of sudden death and congestive heart failure. Applanation tonometry is the method of choice to measure pulse wave velocity and pulse wave analysis. The primary objective will be to assess the effect of a 16 week exercise program on aortic pulse wave velocity as the vascular parameter and gait speed as the physical functioning parameter. The secondary objectives will assess the effect of the exercise program on ultrafiltration rates, weight, SBP, DBP, BNP, hsTroponin, serum calcium, phosphate, albumin, glucose, LDL, HDL, TG, glycated hemoglobin, hemoglobin, CRP, micro RNAs (21, 126, 133, 146a, 221/222 and 210) and hospitalizations.

The investigators propose a pilot project to assess the effect of a 16 week aerobic exercise program on arterial stiffness and cardiovascular risk in the hemodialysis population. The primary objective will be to assess the effect of a 16 week exercise program on aortic pulse wave velocity as the vascular parameter and gait speed as the physical functioning parameter. The secondary objectives will assess the effect of the exercise program on ultrafiltration rates, weight, SBP, DBP, BNP, hsTroponin, serum calcium, phosphate, albumin, glucose, LDL, HDL, TG, glycated hemoglobin, hemoglobin, CRP, micro RNAs (21, 126, 133, 146a, 221/222 and 210) and hospitalizations.

Study Design:

Randomized-controlled study of end stage renal disease patients between the age of 18 and 90 years to assess the effect of exercise on arterial stiffness. Our aim is to have 23 patients in both groups. The study period will be 24 weeks-4 weeks for recruitment, 16 weeks for the intervention and 4 weeks for data collection and analysis. The protocol will be submitted to the MUHC Research Ethics Board.

The following outcomes are of interest:

1. change in gait speed before and after the exercise program
2. change in pulse wave velocity before and after the exercise program
3. change in BNP, blood pressure, dialysis ultrafiltration, hemoglobin, micro RNAs before and after the exercise program

Eligibility Criteria:
Inclusion Criteria:

1. Male or female, aged 18-95 years
2. Able to comply with the study procedures and medication
3. Written informed consent given
4. On a stable in-center hemodialysis regimen (at least 3 times per week) for ≥ 12 weeks prior to recruitment
5. Cardiac evaluation within the year with adequate cardiac function to be able to undergo the exercise program

Exclusion Criteria:

1. Participation in any clinical trial using an investigational product or device during the 30 days preceding recruitment
2. Any physical or psychological disability that would impact study participation, such as severe cerebrovascular disease (ie. hemiparesis, cerebellar ataxia, etc.) or dementia
3. Serum iPTH \> 250 pmol/L within 30 days prior to screening visit
4. Dysrhythmia or severe cardiac disease: CHF Class III-IV; unstable cardiovascular diagnosis (for example MI, CABG, PTCA, CVA, and TIA) within 90 days prior to recruitment
5. Severe peripheral vascular disease
6. Severe hyperkalemia (\>6.5 mmol/L) consistently for the last 2 weeks
7. Current active cancer (excluding basal cell carcinoma of the skin)
8. Poorly controlled hypertension (systolic \> 180mmHg or diastolic \> 100mmHg) within 4 weeks prior to recruitment
9. Anticipated live donor kidney transplant or any other planned major surgery over the study duration
10. History of poor adherence to hemodialysis or medical regimen
11. Any disease or condition, physical or psychological that, in the opinion of the investigator, would compromise the safety of the subject or the likelihood of achieving reliable results or increase the likelihood of the subject being withdrawn