Optimising initiation of dialysis for older people with chronic kidney disease – the UK EQUAL biomarker study.
Chronic kidney disease (CKD) is a major health problem. In England, the estimated cost of treating CKD is £1.4 billion/year, with roughly half of this money being spent on dialysis treatment.
Once a patient’s kidney function drops below 15-20% they are nearing kidney failure. At this point they are encouraged to decide whether they wish to prepare for renal replacement therapy (a transplant or dialysis) or comprehensive conservative care, where support and treatment is provided for problems associated with worsening kidney function, but renal replacement therapy is not used. However, it is estimated that two out of every three older people who meet criteria to be prepared for kidney failure treatment die without having developed it.
Dialysis and the preparation for dialysis have a substantial impact on the lives of people with kidney disease as well as on those of their families, friends and carers. Improving the capability to predict who is likely to reach kidney failure and determining the optimum time for initiating dialysis treatment would allow patients to plan for their future and allow the health care team to target their resources more effectively.
Currently there are a few tools which combine patient information with urine and blood test results to try and predict who is likely to reach kidney failure. However, these tools do not assist in judging when to commence dialysis. Recently there have been advances in identifying potential new protein biomarkers, which may help to guide which patients are likely to reach kidney failure and how quickly this is likely to happen. However, there have not been any large research studies in older adults with advanced CKD evaluating whether these biomarkers can be used to help determine the best time to start dialysis.
The European QUALity Study on the treatment of advanced CKD (EQUAL) is an international research study designed to determine the optimum time to start dialysis in older patients who are nearing kidney failure. This study collected information from participants’ medical records, blood tests and patient experiences collected at repeat interviews. In addition, the EQUAL study included collection of blood biosamples from every recruited patient. The biosamples from the 500 UK participants are available and ready for analysis, alongside 1,147 from 5 other European countries.
Protein biomarker analysis of the EQUAL biosamples would be the first crucial step in integrating new biomarkers with clinical and biochemical data to improve identification of the optimum timing for dialysis initiation. Improving our understanding in this area could have a considerable impact on the lives of patients with CKD.