November 28, 2004

Anaemia in Kidney Disease

Treatment of anaemia may have a protective effect on the kidney, writes Dr David Goldsmith

Most renal patients suffer from anaemia due to depleted levels of erythropoietin (EPO) in the kidney. Currently in the UK there are approximately 19,400 patients on dialysis, and 92 per cent are treated for anaemia.

Anaemia is defined as a haemoglobin level of below 11g/dl and causes a number of debilitating symptoms. These include fatigue, weakness, palpitations, pallor, dyspnoea and headaches.

Anaemia is strongly linked to the development of a dilated left ventricle (as part of left ventricular hypertrophy), which is a potent predictor of premature mortality in patients with chronic kidney disease. Research suggests that treatment of anaemia (along with other associated risk factors) may have a protective effect on the kidney and help with response to treatment.

The management of anaemia in patients with kidney disease has always been led by the renal unit team. It is focused on dialysis patients who are undergoing intensive and repetitive treatment for their kidney disease.

However, there are vast numbers of people with early chronic kidney disease or who are pre-dialysis, as well as growing numbers of transplanted patients, and they would all benefit from aggressive anaemia management.

Routine blood tests

Dialysis patients who are managed within one of the 70 renal units in the UK, have routine monthly blood tests that quickly and easily monitor Hb levels to assess for anaemia. At Hb levels of below 11 g/dl, EPO is often prescribed. It is administered subcutaneously, mainly by renal nurses or anaemia nurses who are integral to patient care.

There is a need for primary care support to help manage the huge numbers of patients likely to progress to end-stage renal failure.

Others remain stable with chronic renal impairment, or some will succumb to other conditions before reaching the need for dialysis and transplantation. Most of these patients could successfully be managed in primary care with appropriate advice from specialist secondary care.

Kidney disease has many associated factors, of which anaemia is one.

Bone disease, blood pressure, diabetes and cholesterol are also linked with renal disease and their optimal management is essential to maximising patient care.

Anaemia should be no different because routine blood pressure monitoring is performed in surgeries - therefore low Hb levels are often known about yet remain unrecognised and unconnected as a risk factor for renal disease.

As anaemia can be detected simply through this standard measure, GPs already have access to the vast number of patients at risk of chronic kidney disease in the primary care population. Patients with diabetes and chronic kidney dis ease are especially likely to be anaemic and ought to be prioritised for anaemia screening.

Secondary care

Currently, the recognition, detection and treatment of renal disease, including renal anaemia, is managed in the specialist secondary care environment when patients arrive in hospital with end- stage renal failure requiring emergency dialysis.

While end-stage disease and dialysis is best handled in this setting, the long-term progression of renal disease through chronic kidney disease stages one to five (see box, above) provides a perfect opportunity for early detection, early access to good quality care and the potential to slow down progression to dialysis and preserve patient independence and health. This is perhaps best handled in primary care.

Renal NSF

The renal NSF part 1 focused on providing better and fairer access to and improving choice and quality in dialysis and kidney transplant services. Part 2 is to follow soon and will recognise that earlier detection and treatment of renal disease and associated factors is important. It is likely to call for renal networks to implement a shared care approach for detecting and treating renal disease.

Responsibility for end-stage renal disease patients and those on life-long dialysis is likely to remain under secondary care management and will include similar practices as currently employed.

However, the management of the vast numbers of early kidney disease patients is likely to fall within the remit of primary care where the stabilisation of comorbidities such as anaemia, blood pressure, bone disease and diabetes will be key.

Methods for referring patients between primary and secondary care will need to be developed. GPs should be encouraged to test for and detect the early signs of renal disease, such as polyuria, excessive tiredness and fatigue, blood pressure problems or proteinurea.

GPs should adopt a simple glomerular filtration rate (GFR) calculation, using serum creatinine, height and weight measurements. This definitive measure of renal function will lead to appropriate referrals to nephrology for secondary care help.

The obesity epidemic in the UK and subsequent increase in diabetics places huge numbers of patients at risk of renal dis ease within primary care. As their kidney disease progresses undetected and associated factors are undermanaged, secondary care is going to find itself deluged with vast numbers of emergency dialysis patients, for which service provision is simply not available.

There are only 314 nephrologists in the UK who are responsible for 37,000 patients (pre-dialysis, dialysis and transplant). Patients who need emergency dialysis are already being turned away for treatment due to lack of equipment and space within renal units.

Diabetes has become a shared care initiative where funding and support has been developed and implemented to give primary care a vital role in managing the disease.

In theory, and in a much changed NHS, a similar approach could be adopted for renal care, another complex and multi-faceted disease area.

There is a need for primary care support to help manage those likely to progress to end-stage renal failure

Dr Goldsmith is a renal consultant at Guy's Hospital, London

Copyright Haymarket Business Publications Ltd. Nov 5, 2004