1. Bicarbonate in CKD with Acidosis trial
January 2012
Dr Miles D Witham

2. Why is it being done?
Mild degrees of metabolic acidosis are common in advanced CKD, and are often treated with bicarbonate
Evidence for beneficial effects on outcomes is very limited
There are potential side effects from the sodium load in bicarbonate therapy
Pilot RCT (Barts, London) suggested slower progression of renal impairment in treatment group; younger pts, few outcomes
Specific commissioning call from the NIHR HTA

3. What is the BiCArb trial?
Multicentre double-blind, placebo controlled RCT
Comparing oral bicarbonate vs placebo
In patients aged 65 yrs and over
With CKD stages 4/5 and acidosis (serum bicarb <22mmol/L)
2 yrs of therapy (0.5 to 1g tds bicarb)
380 patients across 6 or more centres

4. What will be measured?
Measurements will be taken at 0,3,6,12 and 24 months
Primary outcome: Short Physical Performance Battery
Muscular - Grip strength
Renal – change in creatinine, cystatin C
Quality of life (EuroQoL, KDQoL)
Health economic analysis
Safety:
Adverse events, blood pressure

5. Bone and vascular substudy
150 patients (Dundee and Aberdeen)
Vascular:
Arterial stiffness (tonometry)
B-type natriuretic peptide
Bone:
DEXA (bone mineral density and whole body composition)
TRACP-b, Bone specific alk phos

6. Key points relating to trials in older people
‘Organ-specific’ – but designed around older people
Function and quality of life are key outcomes; HTA accepted our arguments around this
Accepted a relaxed approach to exclusion criteria
Commissioning brief gave detailed parameters to follow; we followed them
Dual network adoption
Will provide us with a template for future applications
Sponsor accepts relaxed approach to event reporting
Helps to build infrastructure, collaborations and experience for future trials

7. Thankyou for listening For further details, see: www.bicarb.org.uk