Analysis of the kidney failure risk equation implementation in routine clinical practice and health inequalities in chronic kidney disease care: a retrospective cohort study

Abstract

Background

NICE guidelines recommend GPs use the kidney failure risk equation (KFRE) to identify people with chronic kidney disease (CKD) at higher risk of kidney failure. Albuminuria results are required to calculate KFRE.

Aim

Analyse the implementation of KFRE into clinical practice and investigate if albuminuria testing varied amongst patients with CKD, particularly for underserved groups.

Design and setting

Retrospective cohort study of 23,063 adults in Glasgow from 2013 to 2022.

Method

We evaluated albuminuria testing rates and the predictive performance of KFRE in estimating 5-year kidney failure risk amongst people with CKD. Logistic regression models quantified associations between demographic/clinical variables and albuminuria testing. Amongst people who developed kidney failure, we retrospectively assessed the impact of KFRE on the timing of meeting criteria for referral to renal services.

Results

Albuminuria testing was performed in 44.5% of 10,874 adults with CKD. Females (adjusted odds ratio (aOR) 0.86: 95% CI 0.79–0.93) and those with hypertension (aOR 0.69: 95% CI 0.63–0.77) were less likely to have albuminuria testing. Those aged 40–50 years (aOR 1.83: 95% CI 1.15–2.91), with diabetes (aOR 2.35: 95% CI 2.14–2.58) and living in the least socioeconomically deprived areas (aOR 1.11: 95% CI 1.00-1.23) were more likely to have albuminuria testing. Of 1,352 individuals with incident kidney failure, incorporating KFRE into referral guidelines helped identify high-risk patients early.

Conclusion

KFRE could be calculated for less than half of people due to lack of albuminuria testing. Focus should be given to improving albuminuria testing and inequities identified to allow wider implementation of KFRE.