Chronic kidney disease (CKD) affects 700 million people globally. Two of the main causes of CKD are persistent and abnormally high blood sugars (also known as diabetes) and high blood pressure. Research shows the main causes of CKD are increasing, resulting in more people with CKD. 45,000 patients die each year in the UK due to CKD. Routine monitoring of kidney function and treating underlying causes of kidney disease are essential parts of CKD care. However, the COVID-19 pandemic has affected routine care, increasing the risk of worsening kidney disease. A new tool to help clinicians predict which patients are at greatest risk of kidney disease has been included in national guidelines however, it may not work fairly amongst all patients.
The aims of this study are to measure the impact of the COVID-19 pandemic on patient care for CKD patients; to measure what factors increase a patient’s risk of being missed; and to test if a new tool for predicting which patients are at greatest risk of kidney disease helps to improve patient care in a fair way. Using data from the Clinical Practice Research Datalink, we will analyse anonymised health record data from GP practices for patients across the United Kingdom before and after the COVID-19 pandemic. The findings will be shared with our patient and public involvement group and will be published in journals and presented at conferences. The findings will be also used to make recommendations to improve clinical care for patients with CKD.
Background
CKD is a global public health threat. Risk factors - diabetes and hypertension are increasing in prevalence. Early detection and monitoring are central to national and international CKD strategies. Financially incentivised monitoring of CKD ceased in 2015 in primary care. The COVID-19 pandemic disrupted healthcare delivery and with it routine chronic disease management vital for early detection, monitoring and management of CKD. National CKD audit data shows high variability in CKD care across the UK which results in major health inequalities. It is unclear which patients are at greatest risk of being missed. Predicting the risk of serious kidney disease is vitally important for patients and health systems alike, owing to the major human and financial costs of the disease. The Kidney Failure Risk Equation (KFRE) does this with high accuracy and was included in national NICE CKD guidelines - in August 2021. However, the KFRE lacks extensive validation in Black, Asian, and ethnic populations and its impact on patient and health system outcomes are unknown.
Aims
1. Quantify the impact of the COVID-19 pandemic on CKD care and patient outcomes in UK Primary Care
2. Quantify missing cases of CKD, determine which factors increase the probability of undiagnosed CKD, and its impact on patient outcomes
3. Measure:
a. the impact of including the KFRE in national NICE CKD guidelines on patient and health system outcomes
b. the performance of the KFRE in underserved groups
Methods
We will conduct an interrupted time series to quantify the impact of the COVID-19 pandemic on CKD care. We will create a risk prediction model to determine which patients are at greatest risk of being missed, correlated with patient outcomes. We will quantify the impact of the KFRE model on patient and health system outcomes and performance of the KFRE in underserved groups.
Work Package 1: Measuring the Impact of COVID-19 Pandemic on CKD Care and Patient Outcomes
Primary Outcomes – see appendix 1
1. Number of patients with coded versus uncoded CKD prior to, during and after the COVID-19 pandemic
2. Completeness of CKD care in line with NICE CKD 2021 guidelines – see appendix 2
3. Major adverse renal events: new-onset kidney injury (persistent albuminuria/proteinuria and/or decreasing eGFR <60ml/min/1.73m2; sustained decline of > 50% in eGFR; development of ESKD < 15ml/min/1.73m2 with or without initiation of renal replacement therapy; acute kidney injury; death of renal cause.
4. Major adverse cardiac events: myocardial infarction; stroke; hospitalisation due to heart failure; death of cardiac cause
5. All-cause mortality
6. COVID-19 related death (death within 28 days of acute COVID-19 infection)
Secondary Outcomes – see appendix 1
1. Stratification of findings to Kidney Research UK health inequality themes (age, sex, ethnicity, socioeconomic status, geography, mental health disease) – see appendix 1
2. Stratification of findings to indices of multiple deprivation deciles, and CCG level funding.
3. Prevalence of unscheduled care between patients with coded versus uncoded CKD: A&E attendances; All-cause hospitalisation; Length of hospital stay.
4. Population level outpatient nephrology appointments over time
Work Package 2: Predicting Missing Cases of CKD and their Correlation with Patient Outcomes and Unscheduled Care
Primary Outcomes – see appendix 1
1. Time to event of CKD diagnosis
2. Association between undiagnosed CKD and risk of: major adverse renal events; major adverse cardiac events; All-cause mortality; COVID-19 related death; Unscheduled care – A&E attendances
3. Association between time to event of CKD diagnosis and key independent variables
Work Package 3: Measuring the Impact and Performance of the Kidney Failure Risk Equation in NICE CKD guidelines in UK Primary Care
Primary Outcomes – see appendix 1
Impact
1. Number of patients with measurable KFRE scores pre and post-2021 NICE CKD guidelines update.
2. Number of advice and guidance referrals to nephrology pre and post-2021 NICE CKD guidelines update
3. Number of scheduled care appointments (outpatient appointments) to nephrology pre and post-2021 NICE CKD guidelines update.
4. Changes in major adverse renal events and major adverse cardiac events before and after inclusion of the KFRE in NICE guidelines.
Performance
1. Discrimination and calibration (as measured by area under the receiver operating curve) of the 4-variable, 5-year KFRE in underserved groups of patients with CKD (as measured using Kidney Research UK health inequality themes – age, sex, ethnicity, socioeconomic status, geography, mental health disease).
Secondary Outcomes
1. Population-level changes of KFRE scores over time
2. Read code usage of 'kidney failure risk equation' in the electronic health record
Stuart Stewart - Chief Investigator - University of Manchester
Stuart Stewart - Corresponding Applicant - University of Manchester
Evangelos Kontopantelis - Collaborator - University of Manchester
Philip Kalra - Collaborator - Salford Royal Hospital NHS Foundation
Smeeta Sinha - Collaborator - Salford Royal Hospital NHS Foundation
Tom Blakeman - Collaborator - University of Manchester
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation;CPRD Aurum Ethnicity Record;CPRD GOLD Ethnicity Record