Epidemiology and Classification of Chronic Kidney Disease and Management of Diabetic Nephropathy
Althea Mahon President, European Dialysis & Transplant Nurses Association/European Renal Care Association (EDTNA/ERCA)
a report by
Althea Mahon
President, European Dialysis & Transplant Nurses Association/European Renal Care
Association (EDTNA/ERCA)
Epidemiology and Classification of Chronic Kidney Disease and
Management of Diabetic Nephropathy
BUSINESS BRIEFING: EUROPEAN ENDOCRINE REVIEW 2006
33
Diabetes & Chronic Kidney Disease
Althea Mahon is President of the
European Dialysis & Transplant
Nurses Association/European Renal
Care Association (EDTNA/ERCA), a
multidisciplinary association with
the mission to provide educational
initiatives to assist in the
development of all renal healthcare
professionals. She is a consultant
nurse at Barts and The London
NHS Trust, where she is responsible
for the chronic kidney disease
screening programme. Ms Mahon is
also a visiting honorary senior
lecturer for City University. She has
been working in renal care for the
past 15 years in all areas of
nephrology nursing and represents
renal nursing nationally in many
policy groups.
The number of patients with chronic kidney disease
(CKD) and the subsequent need for renal
replacement therapy (RRT) has reached epidemic
proportion and is anticipated to rise further.
Worldwide, it is estimated that over 1.1 million
patients with end-stage renal disease (ESRD)
currently require maintenance dialysis, and this
number is increasing at a rate of 7% per year.1 If the
trend continues, the number will exceed 2 million
by 2010.2 This figure excludes developing
countries, where there is less availability of and
access to dialysis services, and is therefore an
underestimate of the true demand. The most
common cause of chronic renal failure is diabetic
nephropathy. This article examines the
epidemiology and classification of CKD and the
management of diabetic nephropathy.
The Burden of ESRD and CKD
In the UK, the incidence of ESRD has doubled
over the last ten years and has now reached 101
patients per million of population (pmp).3 This is
below the European and US averages of
approximately 135pmp and 336pmp, respectively.4
Studies that have supplied data on the prevalence of
CKD provide the opportunity to plan nephrology
service requirements and develop stronger working
relationships with the primary care teams in
the community.
Studies such as the National Health And Nutrition
Examination Survey (NHANES), which provided
data on an adult unselected population, estimated
that 4.7% of US adults had CKD stage 3 or higher
(defined as an estimated glomerular filtration rate
(eGFR) of <60ml/min/1.73m2). They also
estimated that up to 11% of the general population
(19.2 million) has some degree of CKD.5 Similarly,
a study of 112,215 patients registered with general
practices in Greater Manchester, Kent and Surrey,
UK, showed a prevalence of 4.9%.4,6 They
also estimated that 5.9 million people may
have stage 1 CKD with normal kidney function.
In the Australian Diabetes, Obesity and
Lifestyle (AusDiab) study of 10,949 patients, a
prevalence of 11.2% of CKD stages 3–5 was found,
but this does not provide an estimate for the
general population.7
Rise in CKD Detection
The rise in diagnosis of CKD is multifactorial but
associated with the ageing population. As technology
and medical interventions are improving, people
live longer, which also impacts on chronic disease
populations. The incidence of diabetes has reached
epidemic proportions throughout the world, with an
expected doubling in the number of patients with
type 2 diabetes in the next 25 years.8 This, in turn,
will lead to an increased incidence of diabetic
1. Lysaght M J, “Maintenance dialysis population dynamics: current trends and long-term implications”, J. Am. Soc.
Nephrol. (2002);13: pp. 37–40.
2. Xue J, Ma J et al., “A forecast of the number of patients with end-stage renal disease in the United States to the year 2010”,
J. Am. Soc. Nephrol. (2001);12: pp. 2,753–2,758.
3. The Renal Association, UK Renal Registry. The Sixth Annual Report (2004), available at: http://www.renalreg.com/
Front_Frame.htm
4. Anandarajah S, Tai T, de Lusignan S et al., “The validity of searching routinely collected general practice computer data
to identify patients with chronic kidney disease (CKD): a manual review of 500 medical records”, Nephrol. Dial.
Transplant. (2005);20(10): pp. 2,089–2,096.
5. Coresh J, Astor B C, Greene T, Eknoyan G, Levey A, “Prevalence of chronic kidney disease and decreased kidney function
in the adult US population: Third National Health and Nutrition Survey”, Am. J. Kidney Dis. (2003);41(1): pp. 1–12.
6. de Lusignan S, Chan T, Stevens P et al., “Identifying patients with chronic kidney disease from general practice computer
records”, Fam. Pract. (2005);22(3): pp. 234–241.
7. Chadban S J, Briganti E M, Kerr P G et al., “Prevalence of kidney damange in Australian adults: the AusDiab Kidney
Study”, J. Am. Soc. Nephrol. (2003);14(90,002): pp. S131–138.
8. Atkins R, “The epidemiology of chronic kidney disease”, Kidney Int. (2005);67(suppl. 94): pp. S14–S18.
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nephropathy, with approximately 30% progressing to
stage 5 CKD. CKD prevalence increases with age,
and men with CKD have a more rapid decline in
renal function and progression of their renal disease
than women.9,10 Some ethnic populations have a
higher prevalence of CKD.11,12 For example, people
from South Asia are at higher risk of CKD linked to
diabetes, as there is a higher incidence of diabetes in
this community.13 Afro-Caribbeans and Africans
are at greater risk of CKD due to their higher
prevalence of hypertension.14 The rise may also be
due to the development of guidelines and simple
blood-test-based formulae (e.g. eGFR) that allow for
easier and earlier diagnosis of CKD and, thus,
increased reporting.
Risk Factors for CKD
Risk factors for CKD include diabetes, cardiovascular
disease, smoking, obesity, sedentary lifestyle and low
socioeconomic status. UK studies have shown a
higher incidence of CKD in deprived areas, which is
consistent with US and Swedish studies.15–19 Obesity
has become a global issue in developed countries,
adding to the population of people with chronic
disease. Those with diabetes and hypertension are at
greatest risk and have a higher rate of renal problems
than the normal population.20 In the UK, diabetic
nephropathy accounts for 18% of new patients
commencing renal replacement therapy and makes up
11% of the prevalent patient population. This is not
solely a UK phenomenon; in 2002, Australia reported
that the country accepted 94pmp for RRT, of which
26% were diabetics. In Pakistan, the incidence of
diabetics entering the programme is 42%, in Japan
37% and in the US 14.8%. This is a worldwide
problem that needs to be addressed.1
Classification of CKD
There are clear guidelines and an internationally
agreed staging system for CKD, which facilitates
diagnosis and management. The National Kidney
Foundation/Kidney Disease Outcome Quality
Initiative (NKF/KDOQI) classification system is
based on eGFR.21 Until recently, the serum
creatinine test was used as the standard test of renal
excretory function. This is not, however, reliable
as a screening test, as the relationship between
GFR and serum creatinine is not linear. By the
time the creatinine becomes elevated, there may
already be a 50% reduction in kidney function. The
most effective way to assess renal function and
gauge the need for further investigation or referral
is by using eGFR, a formula-based calculation of
GFR. There are two recommended formulae to
measure eGFR in patients with moderate to
Table 1: Categories Recommended for the KDOQI Staging of CKD21
CKD Stage GFR Description
1 >90ml/min/1.73 m2* Kidney damage with normal GFR
2 60–89ml/min/1.73 m2* Kidney damage with mildly reduced GFR
3 30–59ml/min/1.73 m2 Moderately reduced GFR
4 15–29ml/min/1.73 m2 Severely reduced GFR
5 <15ml/min/1.73 m2 Kidney failure
*To classify stage 1 or 2 CKD, there must also be other evidence of chronic kidney damage defined by (if present for at least
three months) structural or functional abnormalities of the kidney, e.g. proteinuria and haematuria.
9. Rodriguez-Puyol D, “Aging kidney”, Kidney Int. (1998);54: pp. 2,247–2,265.
10. Neugarten J, Acharya A, Silbiger S R, “Effect of gender on the progression of nondiabetic renal disease: a meta-analysis”,
J. Am. Soc. Nephrol. (2000);11(2): pp. 319–329.
11. Buck K, Feehally J, “Diabetes and renal failure in Indo-Asians in the UK: a paradigm for the study of disease
susceptibility”, Nephrol. Dial. Transplant. (1999);23: pp. 1,555–1,557.
12. “United States Renal Data System. The 2003 Annual Data Report: Incidence and prevalence of ESRD”, Am. J.
Kidney Dis. (2003);42(suppl. 5): pp. S37–41.
13. Lightstone L, Preventing Kidney Disease: The Ethnic Challenge, The National Kidney Research Fund, Peterborough (2001).
14. Raleigh V S, “Diabetes and hypertension in Britain’s ethnic minorities: implications for the future of renal services”, BMJ
(1997);313: pp. 209–215.
15. Roderick P et al., “What determines geographical variation rates of acceptance onto renal replacement therapy in England?”
J. Health Serv. Res. Policy (1999);4(3): pp. 139–146.
16. Drey N, The epidemiology of diagnosed chronic renal failure in Southampton in South West Hampshire Health
Authority, PhD thesis, University of Southampton, Southampton (2000).
17. Young E W, Mauger E A, Jiang K H, Port F K, Wolfe R A, “Socioeconomic status and end-stage renal disease in the
United States”, Kidney Int. 1994;45(3): pp. 907–911.
18. Perneger T V, Whelton P K, Klag M J, “Race and end-stage renal disease. Socioeconomic status and access to health care
as mediating factors”, Arch. Intern. Med. (1995);155(11): pp. 1,201–1,208.
19. Fored C M, Ejerblad E, Fryzek J P et al., “Socio-economic status and chronic renal failure: a population-based case-control
study in Sweden”, Nephrol. Dial. Transplant. (2003);18(1): pp. 82–88.
20. Kissmeyer L, Kong C, Cohen J, “Community Nephrology: audit of screening for renal insufficiency in a high risk
population”, Nephrol. Dial. Transplant. (1999);14: pp. 2,150–2,155.
21. National Kidney Foundation, “K/DOQI clinical practice guidelines for chronic kidney disease: evaluation classification and
stratification”, Am. J. Kidney Dis. (2002);39(suppl. 1): pp. S1–266.
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Epidemiology and Classification of CKD and Management of Diabetic Nephropathy
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advanced CKD: modification of diet in renal
disease (MDRD) and Cockcroft-Gault; but neither
of these is particularly accurate in patients with
mild or normal kidney function. Based on current
evidence, MDRD is the recommended equation,
as it gives an estimate of GFR that is normalised to
a body surface area of 1.73m2 and does not require
the patient’s weight. For Afro-Caribbean patients,
the eGFR is then multiplied by 1.21. The eGFR is
not an appropriate measure for patients with acute
renal failure, as it relies on a stable serum creatinine
for its predictive accuracy.22
An eGFR of 60–90ml/min/1.73m2 on its own,
without another physiological or structural renal
abnormality, is not indicative of CKD. Only a
minority of people with stage 1 or 2 CKD will go on
to develop more advanced renal disease, with symp-
toms usually only appearing at stage 4.9 In order to
diagnose CKD stage 1 or 2, a urinalysis is essential.23,24
CKD Interventions
CKD is progressive, but the progression can be slowed
down with good management. Several studies have
shown that good glycaemic control can decrease the
risk of macrovascular disease in both type 1 and 2
diabetes.25–27 There is also evidence that tight control in
CKD patients can slow the progression from micro-
albuminuria to macroalbuminuria. Interventions to
minimise progression of CKD include lifestyle changes
and reduction in blood pressure, irrespective of the
diagnosis of hypertension or diabetes. The use of
angiotensin-converting enzyme (ACE) inhibitors or
22. Lamb E, Tomson C, Roderick P, “Estimating kidney function in adults using formulae”, Ann. Clin. Biochem. (2005);42:
pp. 321–345.
23. Department of Health, National Service Framework for Renal Services Part Two: Chronic Kidney Disease,
Acute Renal Failure and End of Life Care (February 2005), available at: http://www.dh.gov.uk/
PublicationsAndStatistics/Publications/fs/en
24. Chronic Kidney Disease in Adults: UK Guidelines for Identification, Management and Referral of Adults
(2005), available at: http://www.renal.org/CKDguide/ckd.html
25. Di Landro D, Catalano C, Lambertini D et al., “The effect of metabolic control on development and progression of diabetic
nephropathy”, Nephrol. Dial. Transplant. (1998);13(suppl. 8): pp. 35–43.
The following papers relating to kidney disease can be found on the
website supporting the Business Briefing healthcare series –
www.touchbriefings.com
Secondary Hyperparathyroidism in the Diabetic Patient with Chronic Kidney Disease
Steven Cheng and Daniel W Coyne
Pharmacological Treatment of Diabetic Nephropathy
Bessie A Young
Vascular Calcification in Renal Failure
David Goldsmith
Treatment of Phosphorus and Calcium Disorders in Chronic Kidney Disease
Richard Amerling
Treatment of Anemia in Dialysis Patients
Pietro Pozzoni, Lucia Del Vecchio and Francesco Locatelli
Contrast-induced Nephropathy – Just an Iatrogenic Kidney Disease?
Richard Solomon
Prospective Trials on Anemia of Chronic Disease – The Trial to Reduce Cardiovascular Events with
Aranesp® Therapy
Madhumathi Rao and Brian J G Pereira
Modern Technology and the Reduction of the Cardiovascular Burden of Dialysis Patients
Claudio Ronco
Transition from Paediatric to Adult Renal Care
Alan R Watson
The Increasingly Remarkable Role of Inflammatory Markers as Predictors of Atherosclerotic Risk in
Dialysis Patients
Francesco Locatelli, Pietro Pozzoni and Lucia Del Vecchio
Mahon_refsmoved.qxp 14/12/05 11:35 am Page 35
angiotensin receptor blockers (ARBs) is effective at
reducing progression when there is concurrent
proteinuria. Target blood pressure is below 130/75
millimetres of mercury (mmHg), and this is supported
by the National Institute of Clinical Excellence
(NICE), which found that reducing the blood pressure
to less than 130/75mmHg correlated to a reduction in
the progression of renal disease in type 2 diabetics with
albuminuria.28 Early treatment preserves kidney
function and is cost-effective.23 Other interventions to
minimise progression of CKD in diabetics include
lifestyle changes, e.g. smoking cessation, low-
cholesterol diet and an increase in exercise.
The main hurdle to overcome is to ensure the
implementation of guidelines and develop a global
preventive approach. Locally agreed referral
guidelines from primary care and agreed guidelines
between diabetic and nephrology teams will
improve the detection and management of CKD.
The International Society of Nephrology (ISN) has,
for some time, had a focus on prevention, and the
Commission on Global Advancement of
Nephrology (COMGAN) believes in improving
global outcomes of kidney disease. The new
initiative by the Kidney Disease: Improving Global
Outcomes (KDIGO) group aims to develop a global
approach to managing the CKD epidemic. The
group’s mission statement is: “Improve the care and
outcomes of kidney disease patients worldwide
through promoting co-ordination, collaboration and
integration of initiatives to develop and implement
clinical practice guidelines.” The KDIGO and the
ISN are now working together on the development
of a CKD strategy.29,30
Summary
The majority of the CKD population have one or
more co-morbid condition with a known higher
prevalence in ethnic minorities and lower socio-
economic groups. Without effective prevention and
early detection programmes, the incidence rate of
CKD will continue to rise. Early detection and referral
of CKD patients to nephrology teams is pivotal to
slowing the progression to ESRD and reducing the
demand for dialysis. It has also been demonstrated that
patients referred early have better outcomes.29,31
Diabetic nephropathy progression can be slowed by
effectively tightening glycaemic control, lowering
blood pressure to a minimum of 130/75mmHg with
ACE inhibitors or ARBs, lowering cholesterol and
educating patients on how to lead a healthy lifestyle.
The World Health Organization (WHO) has set a
goal to reduce chronic disease mortality by 2% a year
for the next decade and, therefore, more emphasis
needs to be placed on prevention of CKD and the
need for RRT in this patient population.32 a73
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BUSINESS BRIEFING: EUROPEAN ENDOCRINE REVIEW 2006
26. “The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-
dependent diabetes mellitus. The Diabetes Control and Complications Trial Research Group”, New Engl. J. Med.
(1993);329; pp. 977–986.
27. “Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of
complications in patients with type 2 diabetes (UKPDS 33). UK Prospective Diabetes Study Group”, Lancet
(1998);352: pp. 837–853.
28. McIntosh A, Hutchinson A, Marshall S et al., Clinical Guidelines and Evidence Review for Type 2 Diabetes:
Renal Disease – Prevention and Early Management, ScHARR, University of Sheffield, Sheffield (2002), available
at: http://www.nice.org.uk
29. Li P K-T, Weening J, Dirks J et al., “A report with consensus statements of the International Society of Nephrology 2004
Consensus Workshop on Prevention of Progression of Renal Disease, Hong Kong, 29 June 2004”, Kidney Int.
(2005);67(suppl. 94): pp. S2–S7.
30. Eknoyan G, Lameire N, Barsoum R et al., “The burden of kidney disease: improving global outcomes”, Kidney Int.
(2004);66: pp. 1,310–1,314.
31. Wavamunno M D, Harris D, “The need for early nephrology referral”, Kidney Int. (2005);67(suppl. 94):
pp. S128–S132.
32. World Health Organization, Preventing Chronic Diseases: A Vital Investment, World Health Organization, Geneva
(2005), available at: http://www.who.int/chp/chronic_disease_report/en/index.html
Locally agreed referral guidelines from primary care and agreed
guidelines between diabetic and nephrology teams will improve
the detection and management of CKD.
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