London School of Hygiene & Tropical Medicine

Two simple tests of kidney function and damage can accurately predict risk of death, according to an analysis of 21 studies that included more than 1.2 million participants in Europe, the USA, Australia and Asia. One measure estimates the kidneys' filtration rate with a blood test, the other estimates kidney damage using a urine test for albumin (protein). The study showed that both urine and blood measurements are needed to fully capture the mortality risk that is associated with chronic kidney disease.

The findings appear in an article published in The Lancet today, written by academics from the Chronic Kidney Disease Prognosis Consortium, which includes collaborators from the London School of Hygiene & Tropical Medicine, the University of Southampton and Imperial College, London.

Chronic kidney disease is recognised as a major global public health problem. It affects 10-16% of the adult population in Asia, Australia, Europe and the USA and increases the risk of death, heart disease and kidney failure. The prevalence of chronic kidney disease is increasing worldwide in line with the global obesity epidemic and ageing populations, especially in low- and middle-income countries, which face an increasing burden of non-communicable disease.

Dr Donal O'Donoghue, the National Clinical Director for Kidney Care commented: "This important collaborative study demonstrates the value of clinical scientific partnerships in the UK supported by the Medical Research Council (MRC) and Kidney Research UK. The findings are directly relevant to improving vascular health, which is our biggest challenge in the NHS. "

Professor Peter Mathieson, President of the Renal Association said: "In the kidney world we have long appreciated the significance of impairment of kidney function and/or the importance of finding protein in the urine, but it has only more recently become accepted that these findings have major implications beyond the kidneys and in particular for cardiovascular health. This superb study provides authoritative evidence for this and illustrates the potential power of clinical research for informing health policy across specialties."

The MRC Assessment study at Older Age was one of the 21 pieces of independent research included in this study, led by Professor Astrid Fletcher at LSHTM and Professor Christopher Bulpitt at Imperial College and funded by the MRC. Secondary analysis of kidney function was funded by Kidney Research UK. Dr Dorothea Nitsch (LSHTM), who analysed the data in collaboration with Professor Paul Roderick (University of Southampton), says, "This study was a good example of a major and successful international collaborative effort, to which we provided data on cheap dipstick urine and blood markers. This study shows in a wide range of populations at all ages, that simple markers of kidney damage are associated with cardiovascular risk and death."

The publication of this paper coincides with the annual British Renal Society/Renal Association meeting in Manchester.