Kidney trajectory charts improve GP management of patients with reduced kidney function: a randomised controlled vignette study

Background The stages of chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) reference ranges are currently determined without considering age.

Aim To determine whether a chart that graphs age with eGFR helps general practitioners (GPs) make better decisions about managing patients with declining eGFR.

Design & setting A randomised controlled vignette study amongst Australian GPs using a percentile chart plotting the trajectory of eGFR by age.

Method 373 GPs received two case studies of patients with declining renal function. They were randomised to receive the cases with the chart, or without the chart, and asked a series of questions about how they would manage the cases.

Results In an older female case with stable but reduced kidney function, use of the chart was associated with GPs in the study recommending a longer follow up period, and longer time until repeat pathology testing. In a young male First Nations case with normal but decreasing kidney function, use of the chart was associated with GPs in the study recommending a shorter follow up period, shorter time to repeat pathology testing, increased management of blood pressure and lifestyle management and avoidance of nephrotoxic medications. This represents more appropriate care in both cases.

Conclusion Having access to a chart of percentile eGFR by age was associated with more appropriate management review periods of patients with reduced kidney function, either by greater compliance with current guidelines, or greater awareness of a clinically relevant kidney problem.