Clinical trial NCT04380467: Vitamin D Supplementation in CKD - Vascular Function, Structure and Immune Regulation
Official title: Impact of Vitamin D Supplementation on Vascular Function, Vascular Structure and Immune Regulation in Patients With Chronic Kidney Disease and Low Vitamin D Levels - A Pilot Randomised Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Atherosclerosis
Chronic Kidney Disease
Keywords: Vitamin D
Cholecalciferol
Chronic Kidney Disease
Cardiovascular Disease
Atherosclerosis
Flow Mediated Dilatation
Carotid Intima Media Thickness
CD4+CD28null T lymphocyte
Regulatory T lymphocyte
Lead sponsor: St George's, University of London
Sponsor class: OTHER
First posted: 2020-05-08
Enrollment: 36
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: A pilot study to assess feasibility of methods of an observer-blinded randomised controlled trial of the effect of vitamin D supplementation in Chronic Kidney Disease and low vitamin D levels on markers of vascular function (Flow Mediated Dilatation of Brachial Artery), vascular structure (Carotid Intima Media Thickness) and Immune Regulation (frequencies of CD4+CD28null T lymphocytes ad Regulatory T lymphocytes).

Detailed description: The study is a single (observer) blinded feasibility pilot randomised study. Study subjects will be recruited from clinics run by St George's Hospital Renal Department and randomised to treatment arm or no treatment arm.

In treatment arm, six doses of vitamin D tablets (cholecalciferol 100,000 IU, five capsules total) will be administered on weeks 0, 4, 8, 12, 16 and 20. In the no-treatment arm the participants receive no cholecalciferol. Participants will have serum calcium levels measured at week 12.

All participants will undergo estimation of endothelial function, carotid intima-media thickness, CD4+CD28null and regulatory T cell frequency in week 0 and week 26. The observer will be blinded to whether the patient is in the treatment or no-treatment arm whilst the following tests are performed:

1. Measurement of Brachial Artery Flow Mediated Dilatation
2. Measurement of Carotid Intima Media Thickness
3. Quantification of CD4+CD28null and regulatory T cell frequency

The pilot study will assess feasibility of the study methods.

Eligibility criteria: Inclusion Criteria:

1. Age 18-80 years
2. Calcium \< 2.58mmol/l
3. On an ACE inhibitor/ARB
4. Vitamin D \<75nmol/l
5. eGFR 15- 60ml/min/1.73m2 and stable
6. Informed consent to participate

Exclusion Criteria:

1. Patients already on Vitamin D or calcium supplementation
2. Patients with known malignancies
3. Patients with autoimmune conditions
4. Patients with heart failure (ejection fraction \<40%, Plasma NT pro-BNP\>500pg/ml)
5. Patients with active infection
6. Rapidly deteriorating renal function
7. Recent Acute coronary syndrome or cerebro-vascular event (within the last 6 months)
8. Uncontrolled hypertension (BP\>160 systolic)

Primary outcomes:
measure: Recruitment rate
timeFrame: 3 months
measure: Retention rate
timeFrame: 6 months
measure: Acceptability to patients of randomisation procedures
timeFrame: 6 months
measure: Randomisation procedure
timeFrame: 6 months
measure: Maintenance of single (observer) blinding
timeFrame: 6 months
measure: Adherence to vitamin D supplementation
timeFrame: 6 months
Secondary outcomes:
measure: Witnessed change in FMD between treated and untreated subjects
timeFrame: 6 months
measure: Witnessed change in CIMT between treated and untreated subjects
timeFrame: 6 months
measure: Witnessed change in T lymphocyte subset frequency between treated and untreated subjects
timeFrame: 6 months
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: Debasish Banerjee
state: Tooting
Study officials:
affiliation: St Georges University NHS Foundation Trust
name: Debasish Banarjee
role: PRINCIPAL_INVESTIGATOR
References: