Obesity and Kidney Disease: What is the Connection?
The month of January has forever been the month of resolutions with many choosing to ditch the sweets and join the gym. However, for many these efforts are limited to January and bad habits are quick to remerge. Obesity has been a burden on the health service for many years with the problem, like many people’s waist lines, only continuing to expand.
Recent findings have shown that this problem is no longer just increasing in developed countries but also in developing countries. In fact, worldwide obesity has tripled since 1975. In 2016, more than 1.9 million adults were classed as overweight, of which over 650 million were obese.1 These are shocking statistics for a condition that is preventable. As a global concern, it is important to assess all the potential risks of this problem.
The most common diseases associated with obesity are cardiovascular disease (CVD) and diabetes. However, the associated risks are much greater than this. Being overweight may also increase the risk of certain types of cancer, sleep apnea, osteoarthritis, fatty liver disease and kidney disease.2
Obesity is now recognised as a potent risk factor for the development of renal disease.3 Excess weight has a direct impact on the development and progression of chronic kidney disease (CKD). Globally, the prevalence of diabetic kidney disease rose by 39.5% between 2005 and 2015, coinciding with the increased CKD prevalence.4 In obese individuals, the kidneys have to work harder, filtering more blood than normal to meet the metabolic demands of increased body weight, increasing the risk of kidney disease.
The traditional diagnostic test for renal impairment is creatinine. This test is carried out through the measurement of creatinine levels in the blood to assess the kidneys ability to clear creatinine from the body. This is called the creatinine clearance rate which helps to estimate the glomerular filtration rate (GFR), which is the rate of blood flow through the kidneys.5
Problems arise when using creatinine for CKD testing as a number of factors need to be taken into consideration including age, gender, ethnicity and muscle mass. For this reason, black men and women exhibit higher creatinine levels than white men and women, raising concern over the accuracy of this test for certain patient groups.6 In addition, serum creatinine is not an adequate screening test for renal impairment in the elderly due to their decreased muscle mass.7
The main disadvantage of using creatinine to screen for renal impairment is that up to 50% of renal function can be lost before significant creatinine levels become detectable as creatinine is insensitive to small changes in GFR. Consequently, treatment is not provided at the appropriate time which can be fatal, therefore, an earlier and more sensitive marker for renal function is vital.8
These disadvantages have not only been highlighted in research but also by the national institute for health and care excellence (NICE). NICE updated the classification of CKD in 2004 to include the albumin: creatinine ratio (ACR). They split chronic kidney disease patients into categories based on GFR and ACR. Figure 1 highlights the different categories and risk of adverse outcomes. NICE recommend using eGFR Cystatin C for people in the CKD G3aA1 and higher.9
Figure 1 Classification of Chronic Kidney Disease using GFR and ACR categories.9
Despite these suggestions, Creatinine is still being used for G3a1 and increasing risk levels.
The utility of cystatin C as a diagnostic biomarker for kidney disease has been documented to show superiority of traditional CKD tests. There is no ‘blind area’ making it very sensitive to small changes in GFR and capable of detecting early reductions. Furthermore, this marker is less influenced by diet or muscle mass and has proven to be a beneficial test in patients who are overweight.8
A number of studies support the statement: ‘Cystatin C levels are higher in overweight and obese patients’. This is important because when cystatin c levels are too high, it may suggest that the kidneys are not functioning properly. One study conducted, using a nationally representative sample of participants, found that overweight and obesity maintained a strong association with elevated serum cystatin C. This suggests that weight can affect the levels of cystatin C and therefore the likelihood of developing kidney disease.10
How Randox can Help
The Randox automated Latex Enhanced Immunoturbidimetric Cystatin C tests offers an improved method for assessing CKD risk, combined with a convenient format for routine clinical use, for the early assessment of at risk patients. Randox is currently one of the only diagnostic manufacturers who offer an automated biochemistry test for Cystatin C measurement, worldwide.
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- World Health Organization. Obesity and Overweight . int. [Online] WHO. [Cited: January 22, 2019.] https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight.
- Health Risks of Being Overweight. NIDDK. [Online] National Institute of Diabetes and Digestive and Kidney Diseases. [Cited: March 24, 2019.] https://www.niddk.nih.gov/health-information/weight-management/health-risks-overweight.
- Kidney Health Australia . Obesity and Chronic Kidney Disease: The Hidden Impact. Kidney Health Week/ World Kidney Day 2017. [Online] Kidney Health Australia. [Cited: January 22, 2019.] https://kidney.org.au/cms_uploads/docs/kidney-health-australia-report-obesity-and-chronic-kidney-disease–the-hidden-impact_06.03.17.pdf.
- Neuen, Brendon Lange, et al. Chronic kidney disease and the global NCDs agenda. s.l. : BMJ Global Health, 2017
- Creatinine and Creatinine Clearance Blood Tests. WebMD. [Online] WebMD. [Cited: January 22, 2019.] https://www.webmd.com/a-to-z-guides/creatinine-and-creatinine-clearance-blood-tests#1.
- Lascano, Martin E and Poggio, Emilio D. Kidney Function Assessment by Creatinine-Based Estimation Equations. Cleveland Clinic. [Online] August 2010. [Cited: 16 May 2018.] http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/nephrology/kidneyfunction/.
- Swedko, Peter J, et al. Serum Creatinine Is an Inadequate Screening Test for Renal Failure in Elderly Patients. Research Gate. [Online] February 2003. [Cited: 6 May 2018.] https://www.researchgate.net/publication/8243393_Serum_Creatinine_Is_an_Inadequate_ Screening_Test_for_Renal_Failure_in_Elderly_Patients.
- Mishra, Umashankar. New technique developed to detect chronic kidney disease. Business Line. [Online] 07 May 2018. [Cited: 17 May 2018.] https://www.thehindubusinessline.com/news/science/new-technique-to-detect-chronic-kidney-disease/article23803316.ece.
- National Institute for Health and Care Excellence. Chronic kidney disease in adults: assessment and management: 1 Recommendations. National Institute for Health and Care Excellence. [Online] January 2015. https://www.nice.org.uk/guidance/cg182/chapter/1- recommendations#classification-of-chronic-kidney-disease-2.
- Overweight and Obesity and Elevated Serum Cystatin C Levels in US Adults . Muntner, Paul, et al. 4, s.l. : NCBI, 2008, Vol. 121.
The aim of Biomedical Science Day is to raise the public’s awareness of the importance of biomedical science and the vital role it plays in the world. Randox are dedicated to improving healthcare worldwide through placing a major focus on research and development. The Randox scientists work in pioneering research into a range of common illnesses such as cancer, cardiovascular disease and Alzheimer’s disease.
A recent blog from Doris-Ann Williams, the Chief Executive at BIVDA, explains how “increased funding is not enough to sustain the NHS” and how “we need to make better use of in vitro diagnostics to ensure a successful future”.
The National Health Service (NHS) is a publicly funded, primarily taxation, national healthcare system in the United Kingdom. It was first set-up on July 5th, 1948 by Aneurin Bevan as he believed that everyone, regardless of wealth, should have access to good healthcare. Whilst the NHS is an extremely important aspect of healthcare in the UK, in vitro diagnostics are the heart and soul of the healthcare system as healthcare professionals not only rely on blood tests to diagnose and treat patients, but also to rule out the different contributing causes to a disease state. In vitro diagnostics also plays a key role in monitoring chronic disease states. In vitro diagnostics can also aid in reducing hospital stays, reduce misdiagnosis and support patients in looking after their own health and to deliver personalised treatment plans.
The Randox scientists have developed several niche assays to improve patient diagnosis, monitor treatment and eliminate misdiagnosis.
Adiponectin is a protein hormone secreted by adipocytes with anti-inflammatory and insulin-sensitising properties. It plays an important role in a number of metabolic processes including glucose regulation and fatty acid oxidation. Adiponectin levels are inversely correlated with abdominal visceral fat which have proven to be a strong predictor of several pathologies, including: metabolic syndrome, type 2 diabetes mellitus (T2DM), cancers and cardiovascular disease (CVD). For more information on the importance of testing Adiponectin levels, check out our Adiponectin Whitepaper.
Cystatin C is an early risk marker for renal impairment. The most commonly run test for renal impairment is Creatinine. Creatinine measurements have proven to be inadequate as certain factors must be taken into consideration, including age, gender, ethnicity etc. The National Institute for Health and Care Excellence (NICE) have updated their guidelines, which now recommends Cystatin C as a more superior test for renal impairment due to its higher specificity for significant disease outcomes than those based on Creatinine. For more information on the importance of testing Cystatin C levels, check out our Cystatin C Whitepaper.
Small-dense LDL Cholesterol (sdLDL-C)
LDL Cholesterol (LDL-C) consists of two parts: the large and buoyant LDL Cholesterol and the small and dense LDL Cholesterol. Whilst all LDL-C transports triglycerides and cholesterol to bodily tissues, their atherogensis varies according to their size. As sdLDL-C is small and dense, they can more readily permeate the arterial wall and are more susceptible to oxidation. Research indicates that individuals with a predominance of sdLDL-C have a 3-fold increased risk of myocardial infarction. It has been noted that sdLDL-C carries less Cholesterol than large LDL, therefore a patient with predominately sdLDL-C particle may require nearly 70% more sdLDL-C particles to carry the same amount of cholesterol as the patient with predominately LDL-C particles. For more information on the importance of testing sdLDL-C levels, check out our sdLDL-C Whitepaper.
These three niche in vitro diagnostics tests developed by Randox scientists can aid in reducing NHS costs due to their higher performance compared to the traditional tests. Randox are constantly striving to improve healthcare worldwide.
For more information on the extensive range of Randox third-party in vitro diagnostic reagents, visit: https://www.randox.com/diagnostic-reagents/ or contact email@example.com.
A peer-reviewed study, published in The Lancet Medical Journal suggests there are five types of diabetes. Could diabetes be more complex than we once thought? Could diabetes be segmented into five separate diseases?
What is diabetes?
Diabetes is an incurable disease which prohibits the body’s ability to produce and respond to insulin. Currently, diabetes is classified into two main forms, type 1 and type 2.
Type 1 diabetes is an autoimmune disease which manifests in childhood. In type 1 diabetes, the body’s white blood cells attack the insulin-producing cells in the pancreas. As a result, individuals with Type 1 diabetes rely on the injection of insulin for the remainder of their lives.
Type 1 diabetes affects 10 percent of individuals with diabetes. 96 percent of children diagnosed with diabetes have type 1. Type 1 diabetes in children is commonly diagnosed between the ages of 10 and 14. The prevalence of type 1 diabetes in children and young people (under the age of 19) is 1 in every 430-530 and the incidence of type 1 in children under 14 years of age is 24.5/100,000 (Diabetes UK, 2014).
Type 2 diabetes is the result of insulin resistance, meaning that the pancreas does not produce enough insulin or the body’s cells do not respond to the insulin produced. As type 2 diabetes is a mixed condition, with varying degrees of severity, there are a few methods to manage the disease, including dietary control, medication and insulin injections.
Type 2 diabetes is the most common form of diabetes, affecting 90 percent of individuals with diabetes, and has now become a global burden. The global prevalence of diabetes has almost doubled from 4.7 percent in 1980 to 8.5 percent in 2014, with a total of 422 million adults living with diabetes in 2014. It is expected to rise to 592 million by 2035. In 2012, diabetes accounted for 1.5 million deaths globally with hypertension causing a further 2.2 million deaths. 43 percent of these deaths occurred before 70 years of age. Previously type 2 diabetes was commonly seen in young adults but is now commonly seen in children as well. In 2017, 14% more children and teenagers in the UK were treated for diabetes compared to the year before (World Health Organization, 2016).
In both forms of diabetes, hyperglycemia can occur which can lead to number of associated complications including renal disease, cardiovascular disease, nerve damage and retinopathy.
The novel subgroups of adult-onset diabetes and their association with outcomes: a data-driven cluster analysis of six variables – peer-review study
This new research studied 13,270 individuals from different demographic cohorts with newly diagnosed diabetes, taking into consideration body weight, blood sugar control and the presence of antibodies, in Sweden and Finland.
This peer-reviewed study identified 5 disease clusters of diabetes, which have significantly different patient characteristics and risk of diabetic complications. The researchers also noted that the genetic associations in the clusters differed from those seen in traditional type 2 diabetes.
Cluster One – Severe autoimmune diabetes (SAID)
SAID is similar to type 1 diabetes. SAID manifests in childhood, in patients with a low BMI, have poor blood sugar and metabolic control due to insulin deficiency and GADA. 6% of individuals studied in the ANDIS study were identified with having SAID.
Cluster Two – Severe insulin-deficient diabetes (SIDD)
SIDD is similar to SAID, however, GADA is negative. This means that the characteristics of SIDD are the same as SAID, young, of a healthy weight and struggled to make insulin, however, SIDD is not the result of an autoimmune disorder as no autoantibodies are present. Patients have a higher risk of diabetic retinopathy. 18% of subjects in the ANDIS study were identified with having SIDD.
Cluster Three – Severe insulin-resistant diabetes (SIRD)
SIRD is similar to that of type 2 diabetes and is characterised by insulin-resistance and a high BMI. Patients with SIRD are the most insulin resistant and have a significantly higher risk of kidney disease, and microalbuminuria, and non-alcoholic fatty liver disease. 15% of subjects in the ANDIS study were identified as having SIRD.
Cluster Four – Mild obesity-related diabetes (MOD)
MOD is a mild form of diabetes which generally affects a younger age group. This is not characterised by insulin resistance but by obesity as their metabolic rates are close to normal. 22% of subjects in the ANDIS study were identified as having MOD.
Cluster Five – Mild age-related diabetes (MARD)
MARD is the most common form of diabetes manifesting later in life compared to the previous four clusters. Patients with MARD have mild problems with glucose regulation, similar to MOD. 39% of subjects in the ANDIS study were identified with having MARD.
This new sub-classification of diabetes could potentially enable doctors to effectively diagnose diabetes earlier, through the characterisation of each cluster, including: BMI measurements, age, presence of autoantibodies, measuring HbA1c levels, ketoacidosis, and measuring fasting blood glucose levels. This will enable a reduction in the incidence of diabetes complications and the early identification of associated complications, and so patient care can be tailored, thus improving healthcare (NHS, 2018) (The Week, 2018) (Ahlqvist, et al., 2018) (Collier, 2018) (Gallagher, 2018).
The Randox diabetes reagents cover the full spectrum of laboratory testing requirements from risk assessment, using our Adiponectin assay, to disease diagnosis and monitoring, using our HbA1c, glucose and fructosamine assays, to the monitoring of associated complications, using our albumin, beta-2 microglobulin, creatinine, cystatin c, d-3-hydroxybutyrate, microalbumin and NEFA assays.
Whilst this study is valuable, alone it is not sufficient for changes in the diabetes treatment guidelines to be implemented, as the study only represents a small proportion of those with diabetes. For this study to lead the way, the clusters and associated complications will need to be verified in ethnicities and geographical locations to determine whether this new sub-stratification is scientifically relevant.
Ahlqvist, E. et al., 2018. Novel subgroups of adult-onset diabetes and their association with outcomes: a data-driven cluster analysis of six variables. [Online]
Available at: http://www.thelancet.com/journals/landia/article/PIIS2213-8587(18)30051-2/fulltext?elsca1=tlpr
[Accessed 16 April 2018].
Collier, J., 2018. Diabetes: Study proposes five types, not two. [Online]
Available at: https://www.medicalnewstoday.com/articles/321097.php
[Accessed 16 April 2018].
Diabetes UK, 2014. Diabetes: Facts and Stats. [Online]
Available at: https://www.diabetes.org.uk/resources-s3/2017-11/diabetes-key-stats-guidelines-april2014.pdf
[Accessed 16 April 2018].
Gallagher, J., 2018. Diabetes is actually five seperate diseases, research suggests. [Online]
Available at: http://www.bbc.co.uk/news/health-43246261
[Accessed 16 April 2018].
NHS, 2018. Are there actually 5 types of diabetes?. [Online]
Available at: https://www.nhs.uk/news/diabetes/are-there-actually-5-types-diabetes/
[Accessed 16 April 2018].
The Week, 2018. What are the five types of diabetes?. [Online]
Available at: http://www.theweek.co.uk/health/92048/what-are-the-five-types-of-diabetes
[Accessed 16 April 2018].
World Health Organization, 2016. Global Report on Diabetes, Geneva: World Health Organization.
On 8th March 2018, Randox Reagents are supporting World Kidney Day! World Kidney Day is an annual campaign and partnership to raise awareness of the importance of our kidneys to our overall health and to reduce the frequency and impact of kidney disease and its associated health problems worldwide.
This year, the World Kidney Day theme is: “Kidney Disease and Women’s Health: Include, Value, Empower”. Chronic kidney disease affects approximately 195 million women worldwide and it is currently the 8th leading cause of death in women, with close to 600,000 deaths per year.
Chronic kidney disease in women has increased over the years. Women over the age of 50 and African American women have seen the highest rise of kidney failure. This has been attributed to obesity, diabetes and high blood pressure. It is important that women are screened for renal impairment as although treatment of kidney disease in men and women are the same, the complications associated with renal impairment in women is greater than in men. The complications women are faced with due to renal impairment include: irregular periods, diminished sex drive and difficulties conceiving. Whilst it is difficult for a woman with renal impairment to conceive, it is not impossible, however, 50% of babies born to women on dialysis survived with most being born prematurely due to high blood pressure. There are several measures that women can take to reduce their likelihood of developing renal impairment or manage their symptoms including; lifestyle changes, medication to control associated problems, dialysis and kidney transplant.
The standard marker for renal functional is creatinine as creatinine clearance gives a measure of the glomerular filtration rate (GFR), however, creatinine levels are unreliable in individuals who are obese, malnourished, have liver cirrhosis or reduced muscle mass. Due to this, Randox developed an automated test for Cystatin C, a superior marker of kidney dysfunction.
The Randox Cystatin C assay
Cystatin C is a small (13kDa) cysteine proteinase inhibitor that is produced at a constant rate by all nucleated cells. The small molecular weight of cystatin C allows it to be completely removed and broken down by the kidneys. Therefore, levels remain steady if the kidneys are working efficiently and the Glomerular Filtration Rate (GFR) is normal.
There are several studies that have documented the superiority of cystatin C compared to creatinine as a marker of GFR function. Unlike creatinine, cystatin C does not have a ‘blind area’ meaning it is extremely sensitive to very small changes in GFR and therefore capable of detecting early reductions in GFR. Up to 50% of renal function can be lost before significant creatinine levels are detected. GFR estimates based on cystatin C are less influenced by diet or muscle mass compared to GFR estimates based on creatinine, therefore, Cystatin C is also beneficial if the patient is overweight, elderly or has a lot of muscle mass. Cystatin C is also beneficial if previous kidney function tests were inconclusive.
World Kidney Day and Randox are working towards improving healthcare globally. With continuous investment into R&D, Randox are striving to develop the earliest biomarker for renal function to prevent serious complications.
Acetaminophen is a commonly used medicine for pain-relief. During cold and flu season, it is common to resort to pain-relief medicines to relieve headaches, and ache and pain symptoms associated with a cold or flu as there is no cure. However, the therapeutic range for acetaminophen is 10-30 mg/l, which is small and very easy to go over. During cold and flu season, it is important to monitor the amount of paracetamol entering your body as acetaminophen is more dangerous than suspected. At therapeutic levels, acetaminophen does not produce any adverse effects, however, long-term treatment, prolonged use, and taking a few more than the recommended dose can be severely damaging and fatal. Accidental acetaminophen overdose took the lives of 1,500 people in the U.S between 2001 and 2010. The Randox Acetaminophen assay is used to determine the concentration levels of acetaminophen in the blood to determine if an overdose has taken place.
It is commonly recognised that acetaminophen overdose causes hepatotoxicity, but it is less commonly recognised that it can also cause nephrotoxicity in less than 2% of patients. Nephrotoxicity is toxicity of the kidneys and is often associated with a reduced amount of glutathione which is important for normal cellular metabolism in the kidneys. The Randox Glutathione Reductase assay is required for the regeneration of reduced glutathione. Glutathione is often discussed in association with the Randox Glutathione Peroxidase, which requires reduced glutathione for activation. Both Glutathione reagents are unique to Randox.
Acute renal failure due to acetaminophen manifests as acute tubular necrosis, which can occur alone or in combination with hepatic necrosis. Nephrotoxicity can also occur when the therapeutic levels of acetaminophen are not exceeded. This most commonly occurs when acetaminophen is taken in combination with alcohol. Upon testing acetaminophen levels and the results fall within the therapeutic range, the Randox Ethanol assay can test alcohol levels to determine if a combination of alcohol and acetaminophen caused nephrotoxicity. Renal impairment may be more common than previously suspected as acute renal failure occurs in 10-40% of patients with severe hepatic necrosis. Upon testing acetaminophen to determine toxicity, Randox also offer the following renal tests to test for nephrotoxicity:
For more information visit: https://www.randox.com/acetaminophen
To request an application for your specific analyser, contact firstname.lastname@example.org
On 9 March 2017, Randox Reagents are celebrating World Kidney Day! World Kidney Day is a global campaign aimed at raising awareness of the importance of our kidneys to our overall health. It aims to reduce the frequency and impact of kidney disease and its associated health problems worldwide.
This year, the World Kidney Day promotes education on the harmful consequences of obesity and its association with kidney disease, advocating healthy lifestyle and health policy measures that make preventive behaviours an affordable option.
With this in mind, throughout the week we have been sharing on social media some interesting facts on diagnostic tests which can help aid an early risk assessment of kidney disease in obese patients, allowing preventative action to be taken before any serious damage occurs. The tests of focus this week included cystatin C, adiponectin and microalbumin…
The creatinine test is routinely run for patients who are suspected for deteriorating kidney function, however this test has limitations. Cystatin C is an alternative test, and is particularly useful in patients where creatinine measurements are not suitable e.g. individuals who are obese, malnourished, have liver cirrhosis or reduced muscle mass. Importantly, unlike creatinine, cystatin C does not have a ‘blind area’ – up to 50% of kidney function can be lost before significant creatinine elevation occurs. Cystatin C is extremely sensitive to very small changes in kidney function and is therefore capable of detecting early stage kidney dysfunction. The cystatin C test therefore allows preventative measures to be taken much earlier and before significant kidney function decline.
There is substantial evidence that excess visceral fat is the main driving force for almost all of the disorders associated with the metabolic syndrome, including CKD.1,2 The adiponectin test from Randox can accurately assess levels of abdominal visceral fat, independent of age, race or fitness level.3,4 Assessing adiponectin, and therefore visceral fat levels, can help assess risk of CKD, as well as a range of other illnesses such as pre-diabetes, CVD and various cancers.
The microalbumin test detects very low levels of a blood protein called albumin, in urine. The detection of albumin in urine can be an indicator of kidney injury and can result in irreversible damage if left untreated. Low albumin concentrations in the urine are the earliest marker of kidney damage and therefore enable preventative measures to be taken. Microalbumin testing can identify individuals with diabetic nephropathy approximately 5-10 years earlier than proteinuria tests helping reduce the frequency of end stage renal disease.
Both World Kidney Day and Randox are working towards improving healthcare worldwide. With continuous investment in R&D, Randox are helping with the risk assessment and earliest detection of renal function problems. By assessing one’s risk of kidney problems (with the adiponectin test), it can give patients (obese and other) the tools to prevent kidney problems further on down the line. With early diagnosis (through the cystatin C and microalbumin tests) it will be possible to keep kidney problems from getting worse, therefore lowering the number of those diagnosed with CKD worldwide.
- Precision test detects minute deterioration in kidney function
- Identifies patients at early stages – missed by current testing
- NICE says new test regime could cut the number of patients on medication and dialysis by up to 20%
- Chronic kidney disease affects older people and more common in women
- Unchecked, CKD can eventually cause kidney failure and death
- CKD linked to diabetes, hypertension and cardiovascular disease
Millions of people in the UK are needlessly suffering from advanced kidney disease, because of a ‘blind spot’ in current testing methods. The traditional test used by the NHS to identify kidney dysfunction, measures the level of a waste product (Creatinine), which is only raised when up to 60% of the kidney has already been damaged. This damage is irreversible, with dialysis or transplant the only available therapies.
As kidney disease progresses, waste builds up in the blood which can have a significant impact on other key areas of the body; impairing heart health, weakening bones, reducing immune response and damaging the central nervous system. If left unchecked, CKD can cause kidney failure and death.
With early detection, the progression of CKD can be prevented; in response to this the National Institute for Health and Care Excellence, has drafted new guidance for doctors to improve diagnosis and identify kidney dysfunction in the earliest stages. The health watchdog makes it clear that a highly sensitive test for the biomarker Cystatin C, should be used alongside the traditional creatinine test, for more accurate and earlier identification of kidney function deterioration.
Cystatin C is a protein produced by the body at a constant rate, its small molecular weight allows it to be completely broken down and removed by the kidneys; levels therefore, remain steady if the kidneys are working efficiently and the glomerular filtration rate (GFR) is normal. If kidney function deteriorates, Cystatin C concentrations rise.
Testing for cystatin c means doctors can pick up on even the smallest changes in GFR, identifying a drop in kidney function at the earliest opportunity. Once a problem has been spotted early it can be managed through medication and/or changes to diet and lifestyle, preventing chronic kidney disease from occurring.
Around 2 million adults in England have CKD – but as it is largely asymptomatic and often undiagnosed, it is thought a further 1 million could also be suffering from the advanced stages of the disease. Dr Gilbert Wieringa, Consultant Biochemist at Bolton NHS Foundation Trust, a keen advocate of the test commented:
“I welcome the fact that NICE now recognises Cystatin C as a key biomarker in the differential diagnosis of CKD. The ready availability of this blood test ensures the right treatment can be started for the right patient in the right time in turn helping to prevent or delay progression of CKD, reducing or delaying complications, and reducing the risk of cardiovascular disease. It provides a key example where investment in a diagnostic test helps reduce far greater cost burdens of managing secondary complications further down the line”
NICE says that while using the cystatin c test will increase the cost of diagnosis “accuracy is expected to improve and fewer people are expected to require treatment and monitoring”.
Dr Peter FitzGerald, MD at UK Biotech firm Randox, which has created a cystatin C test for use in every standard hospital lab in the UK, believes the new diagnostic method could have a significant impact on the financial burden of CKD on the NHS:
“CKD is closely linked with diabetes, obesity, stoke and cardio vascular disease – as we see these conditions increase across the UK, so too will the prevalence of CKD, but if we can catch kidney function damage early, we can prevent CKD and prevent the need for expensive medical interventions such as dialysis, the cost of which per patient, per year is around £31,000. Needless to say, it also comes at considerable personal expense, but this does not have to be the way.”
NICE estimates that up to 20% of the current CKD population may not have needed medication, if the new testing method was introduced and says “savings are expected at a local level as a result of this change.”