11 March 2021 marks World Kidney Day (WKD), with this year’s theme being “Living Well with Kidney Disease”.

Kidneys are key to our health and wellbeing; their main function is to remove toxins and excess water from our blood, resulting in urine. Kidneys also help to control our blood pressure by carefully controlling the salt and water in our body. They support the production of red blood cells and play a large role in keeping our bones healthy.

In this blog, we discuss how real world evidence can provide population based insights that support kidney disease research, to improve patient outcomes.

What is kidney disease?

Kidney disease occurs when the kidneys are damaged and cannot filter blood the way they should. When kidneys fail, harmful waste products build up in the body, blood pressure may rise, and the body may retain excess fluid which may lead to shortness of breath caused by water in the lungs. When this happens treatment to replace the work of the failed kidneys prescribed by the patient’s GP may be required. Kidney disease is common, can affect anyone, and there is currently no cure.

There are broadly two types of kidney disease, chronic and acute. Acute kidney injury (AKI) is a sudden drop in kidney function, often as a complication of another serious illness. AKI affects 1 in 5 people admitted to hospital as an emergency for unrelated acute illness. In the UK around 100,000 deaths each year are associated with AKI, however, research shows that 30% of these could be prevented with the right care and treatment, starting with their routine interactions with their GP. The costs to the NHS of AKI are estimated to be between £400 - £600 million per year.

Chronic kidney disease (CKD) is defined as the presence of kidney damage for greater than 3 months. Around three million people in the UK have chronic kidney disease (CKD). Uncontrolled diabetes and high blood pressure are the biggest causes of CKD and causes around 45,000 premature deaths in the UK. Total NHS expenditure attributable to CKD is estimated at £1.45 billion, equivalent to 1.3% of NHS expenditure in England.

How is kidney disease diagnosed and managed, and is there room for improvement?

Blood tests measuring the amount of creatinine or waste in the blood is used to diagnose CKD. These results combined with age, size, gender and ethnic group are used to calculate estimates of glomerular filtrate rates (eGFR). These results, combined with a urine test measuring the levels of albumin to creatinine ratio, provides a picture of kidney function and is used to determine the stage of CKD 1-5, an indication of the damage to the kidneys. The higher the score the more severe the disease. Depending on the stage of the CKD, treatments initiated by the patients’ GP range from lifestyle changes and medicine to control associated problems such as high blood pressure and high cholesterol, to dialysis and kidney transplant for those with advanced stage 5 CKD. Primary care plays an important role in the monitoring and management of CKD, only a small proportion of people with mild or moderate CKD will progress to end-stage disease. Therefore, the main purpose of monitoring people with CKD is to undertake risk stratification to identify patients at risk of disease progression and to identify those at risk of other complications such as cardiovascular disease and AKI.

The past 15 years has seen sustained efforts to improve the identification, management and monitoring of CKD. In the UK this included the incorporation of states 3-5 CKD into the Quality and Outcomes Framework (QOF), a primary care pay for performance system. Identifying patients at an increased risk of kidney disease and who might benefit from a therapeutic or preventative intervention remains an important challenge.

Real world data can help us understand how well we are doing at identifying and diagnosing patients at risk of kidney disease, how well treatments are working and highlight where improvements are required. In this case, real world data from General Practice (GP) primary care, such as that held in IQVIA Medical Research Data (incorporating data from The Health Improvement Network (THIN), a Cegedim Database), is the best suited as this is the setting for CKD diagnosis and treatment in the UK.

Harnessing real world data to support kidney disease management

Real world data can be used to conduct population studies. The use of de-identified patient records would enable researchers to study the effectiveness of CKD diagnosis and management strategies by observing outcomes recorded within routine patient care.

IQVIA Medical Research Data includes non-identified electronic patient health record data from over 18 million patients collected from UK GP Practices. IQVIA implement a wide variety of privacy-enhancing technologies and safeguards to protect individual privacy while maximising the utility of the data for medical research and treatment analysis.

IQVIA Medical Research Data captures coded demographic, administrative data, clinical events, prescriptions, with secondary care and death information. IQVIA Medical Research Data covers approximately 4.5% of the UK population, with the UK uniquely positioned with universal free at point of care healthcare through its National Health Service. Harnessing this data could help provide researchers attain a deeper understanding of the prevalence, diagnosis, and management of the disease.

A UK cohort study examined the prevalence of stage 3-5 CKD in primary care, the study concluded that the prevalence of stages 3 – 5 CKD was lower than previous estimates. The researchers attributed this to the misclassifications of CKD disease in primary care, resulting in sub-optimal care for incorrectly classified patients. In 2016, a study evaluated the performance of the Qkidney, multivariate risk scores, developed to predict the 5-year risk of developing moderate-severe kidney disease, the researchers conducted a prospective cohort study in 364 practices. The results showed that Qkidney scores were useful tools for predicting 5-year risk of moderate-severe kidney disease in the UK, supporting the case for better and more widespread implementation of the tool in clinical practice. A further 2016 study examined the risk of moderate to advanced (stage 3-5) CKD in patients with psoriasis. A population-based cohort was constructed, data was collected prospectively in on 143 883 adults with psoriasis and matched with a control group. The study concluded that moderate to severe psoriasis is associated with an increased risk of moderate to advanced CKD, highlighting the need for earlier management and monitoring of these patients to reduce the potential risk of development of severe CKD. A cross sectional observational study is examining the pathways of patients with CKD, due to concerns about the lack of precision around the timing of referrals to secondary care for patients whose disease had progressed. Using primary care data, the researchers will be exploring the practical application of using the Kidney Failure Risk Equation (a generalisable CKD risk prediction model), to predict end-stage renal failure in patients with CKD. The aim is to compare the numbers of CKD patients referred to secondary care using this model with those referred using the current NICE-based criteria, whose thresholds differ from the model. Pharmacist-led services such as Interface Clinical Services, an IQVIA company, can provide support to GPs in the management of long-term conditions such as CKD. By assessing the patient’s latest GFR trends, they can determine the stage of CKD and if it falls between 3 – 5, assist the primary care team in planning the patient’s care in line with the latest QOF and care guidelines. The ultimate end goal is to ensure appropriate disease management and monitoring of the disease, and to enable timely referrals to secondary care for patients approaching advanced disease.

Living well with kidney disease

In addition to early diagnosis, improving the management of CKD through effective symptom management is important, and seeking the direct views on the quality of life outcomes that matter most to patients living with CKD is critical to this. This year’s WKD theme, advocates holistic symptom management for patients by identifying and managing symptoms that cause suffering, these include pain, sleep issues, anxiety, depression, stress, mobility, frailty.

Health-related quality of life outcomes and other patient reported outcomes are vital in assessing patient perspectives and experiences. Being able to capture patient reported experience and outcomes measures (PREMs and PROMs) is important in helping us understand the outcomes that matter most to patients. Tools and resources that enable us to collect and analyse such data are crucial to identifying the symptoms that are most burdensome to patients, understanding this allows for the development of education and management strategies that will alleviate these symptoms and improve the daily living experiences of CKD patients. Tools such as IQVIA connection, that enable data to be collected directly from patients are key to supporting the holistic management of patients.

Real world evidence can provide insights into disease diagnosis and management. Through the analysis of routine clinical data, we are able to address gaps in our understanding of kidney diagnosis and treatment and identify areas where improvements are required to support better management and care of patients. IQVIA Medical Research Data, as a source of population-based insights, is updated with the latest available information several times a year, giving researchers the opportunity to evaluate the impact of new research and treatment guidance.

For more information, please contact james.philpott@iqvia.com.