Vitamin D and Cardiac Autonomic Tone in Hemodialysis
Information source: University of Calgary
ClinicalTrials.gov processed this data on August 23, 2015 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Cardiovascular Disease; Sudden Cardiac Death
Intervention: Alfacalcidol (Dietary Supplement); Ergocalciferol (Dietary Supplement)
Phase: Phase 2
Status: Active, not recruiting
Sponsored by: University of Calgary Official(s) and/or principal investigator(s): Dr. Sofia B Ahmed, MD, MMSc, Principal Investigator, Affiliation: University of Calgary Dr. Derek Exner, MD, MPH, Principal Investigator, Affiliation: University of Calgary, Libin Cardiovascular Institute Dr. Brenda Hemmelgarn, MD, PhD, MN, Principal Investigator, Affiliation: University of Calgary
Summary
Despite advances in treatment of conventional cardiovascular risk factors, patients with
kidney disease remain at high risk for fatal cardiac events. To date, kidney disease affects
approximately 2 million Canadians; however, this patient population remains grossly
understudied due to the complex nature of the disease. The inadequacy of the literature to
address the cardiovascular-related mortality rates in those with kidney disease reflects the
urgent need for investigation of novel risk factors.
One cardiovascular risk factor which has recently been validated is the clinical measurement
of cardiac autonomic tone (CAT). CAT refers to the amount of activity contributed by the
stimulatory and inhibitory limbs of the cardiac autonomic nervous system, which work in
concert with one another to control heart rate. CAT can be quantified computer analysis of
heart rate over time, captured by a simple Holter electrocardiogram (ECG) recording.
Abnormal CAT, which occurs when the autonomic system does not control heart rate properly in
response to physical demands or stress, is associated with risk of adverse cardiovascular
events in both healthy and high risk populations. It has recently been shown that patients
with severe kidney disease demonstrate significant CAT abnormalities, thus exaggerated
susceptibility to cardiac death.
Vitamin D (VD) deficiency is also common in this patient population due to the fact that the
kidney plays a crucial role in VD metabolism. Given that VD deficiency is an established
cardiovascular risk factor on its own, it is possible that kidney disease patients
experienced compounded risk due to the combination of VD deficiency and abnormal CAT.
However, no study has ever investigated whether VD deficiency influences CAT in healthy or
diseased populations. To our knowledge, this will be the first trial to ever examine the
effect, if any, of different VD supplementation treatments (standard of care vs.
combination) on CAT in a population burdened with overwhelming risk and incidence of
cardiovascular and sudden cardiac death risk.
Clinical Details
Official title: Vitamin D Supplementation and Cardiac Autonomic Tone in Hemodialysis Patients: A Blinded, Randomized-controlled Trial
Study design: Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention
Primary outcome: LF:HFLF:HF LF:HF
Secondary outcome: SDNNSDANN pNN50% LF HF
Eligibility
Minimum age: 18 Years.
Maximum age: N/A.
Gender(s): Both.
Criteria:
Inclusion Criteria:
- age ≥ 18 years
- 3x weekly hemodialysis outpatient within Calgary for at least 3 months prior to
enrolment
- physician consent to participate in VD supplementation regimen
- ability and agreement to cease any VD medication for 4 weeks prior to initiation of
study
- able to comprehend study and provide oral and written consent in English
Exclusion Criteria:
- any major cardiovascular event (new onset arrhythmia, hospitalization for a cardiac
event) noted in patient chart within the 6 month period prior to initiation of the
study
- currently on VD therapy/refusal to cease VD therapy for 4 weeks prior to initiation
of study
- physician anticipates death or adverse event within the next year- known discharge
from hemodialysis (transfer to peritoneal dialysis, kidney transplant)
Locations and Contacts
Foothills Medical Centre - University of Calgary, Calgary, Alberta T2N 2T9, Canada
Northland Hemodialysis Clinic, Calgary, Alberta T2L 2J8, Canada
Sheldon M. Chumir Health Centre, Calgary, Alberta T2R 0X7, Canada
Additional Information
Related publications: Mann MC, Exner DV, Hemmelgarn BR, Turin TC, Sola DY, Ahmed SB. Impact of gender on the cardiac autonomic response to angiotensin II in healthy humans. J Appl Physiol (1985). 2012 Mar;112(6):1001-7. doi: 10.1152/japplphysiol.01207.2011. Epub 2012 Jan 5. Drechsler C, Pilz S, Obermayer-Pietsch B, Verduijn M, Tomaschitz A, Krane V, Espe K, Dekker F, Brandenburg V, März W, Ritz E, Wanner C. Vitamin D deficiency is associated with sudden cardiac death, combined cardiovascular events, and mortality in haemodialysis patients. Eur Heart J. 2010 Sep;31(18):2253-61. doi: 10.1093/eurheartj/ehq246. Epub 2010 Aug 5. Lahiri MK, Kannankeril PJ, Goldberger JJ. Assessment of autonomic function in cardiovascular disease: physiological basis and prognostic implications. J Am Coll Cardiol. 2008 May 6;51(18):1725-33. doi: 10.1016/j.jacc.2008.01.038. Review. Mann MC, Exner DV, Hemmelgarn BR, Sola DY, Turin TC, Ellis L, Ahmed SB. Vitamin D levels are associated with cardiac autonomic activity in healthy humans. Nutrients. 2013 Jun 10;5(6):2114-27. doi: 10.3390/nu5062114.
Starting date: January 2013
Last updated: September 16, 2014
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