Does oral sodium bicarbonate therapy improve function and quality of life in older patients with chronic kidney disease and low-grade acidosis (the BiCARB trial)? Study protocol for a randomized controlled trial (Trials)

Background: Metabolic acidosis is more common with advancing chronic kidney disease, and has been associated with impaired physical function, impaired bone health, accelerated decline in kidney function and increased vascular risk. Although oral sodium bicarbonate is widely used to correct metabolic acidosis, there exist potential risks of therapy including worsening hypertension and fluid overload. Little trial evidence exists to decide whether oral bicarbonate therapy is of net benefit in advanced chronic kidney disease, particularly in older people who are most commonly affected, and in whom physical function, quality of life and vascular health are at least as important outcomes as decline in renal function.Methods/DesignBiCARB is a multi-centre, double-blind, placebo controlled, randomised trial evaluating the clinical and cost-effectiveness of oral sodium bicarbonate in the management of older people with chronic kidney disease and severely reduced glomerular filtration rate (GFR) who have a mild degree of metabolic acidosis. The trial will recruit 380 patients from renal, Medicine for the Elderly, and primary care services across centres in the United Kingdom. Male and female patients aged 60 years and older with an estimated glomerular filtration rate of