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	Diversity of patient populations			Compliance
	Polypharmacy			Medication reviews
	Drug-induced admissions			Savings to be made

There are a number of factors specific to renal patients which makes prescribing drugs to them particularly complicated. They present a pharmaceutical challenge, not only in terms of the appropriateness of drug therapy, but also with regard to their need for information about their medication.

However, when looking at the importance of renal drugs we must also consider the burden of drug therapy on renal patients and the complex issues we must address in their management.

We have to bear in mind the diversity of the populations we see, the problems associated with polypharmacy (including the increased potential for drug interactions), drug-related problems and drug-related admissions, and the challenges of compliance with prescribed therapies.

We should never forget our collective responsibility for the drug management of renal patients.

Diversity of patient populations

The term renal patient is misleading when we consider the wide variety in the type of patients that we see.

For predialysis populations, drug therapy is targeted towards avoidance of drugs which may exacerbate existing renal impairment or precipitate end-stage failure. It also includes pharmacological therapies to correct systemic abnormalities or alleviate longer-term concerns such as anaemia, hypertension and bone disease. Furthermore, there is the challenge of constantly optimising therapy in the light of ongoing research and drug developments.

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For patients with end-stage failure, there is a host of medical issues and number of complications relating to the broad categories of uraemic symptoms, abnormalities in fluid and electrolyte balance, and changes in metabolism -- each of which has its own drug regimen, which can be at least partially addressed by drug therapies.

This obviously gives rise to a wide range of drug-treatment options -- with the potential of confusing, not only our patients, but also ourselves!

One point I find of clear concern is the excess of cardiovascular morbidity and mortality related to anaemia. Indeed, three-quarters of patients entering a renal-replacement programme have some degree of left-ventricular hypertrophy which is further compounded by anaemia, facilitating the development of heart failure.

We already have clear evidence-based guidelines for the management of anaemia in end-stage renal failure but we fail to achieve recommended haemoglobins and irons in many of our patients. Perhaps it is time to review how we are trying to address some of these concerns.

We have drug treatments which can effectively correct many of these complications in most of our patients and we have a responsibility to target resources and systems for monitoring of patients to improve their outcomes.

Transplant recipients pose a further challenge. These individuals will, not only be expected to adhere to variable doses of lifelong immunosuppression with their own well-documented side-effects and neoplastic potential, but also will receive a variety of short-course treatments for concurrent complaints or post-transplant complications. This is of particular importance in the immediate post-transplant period, where there is the greatest risk of drug-related morbidity and where adherence is of heightened importance.

It is clear that drug treatments are of obvious importance for our patients and that we are responsible for a broad range of populations with a large variety of indications for these drug therapies. As a result, patients need to be properly managed and provided with information about their medication, not only at the right time, but also the most appropriate manner.

Polypharmacy

Renal patients take a lot of tablets. This confers a higher incidence of drug-related problems and a greater risk of drug-related admissions compared with other populations.

The large number of medications taken by dialysis-dependant patients is well documented, with studies in the US describing patients taking on average 10 prescribed and two non-prescribed drugs.

In the UK, patients take slightly fewer medications, with approximately seven to nine prescribed therapies being commonly reported.

However, it is not only the number of drugs taken that contributes to confusion. It is also the variability of dosing patterns, which may change on a daily basis.

Antihypertensives may be omitted on dialysis days or taken after dialysis sessions. Other drug regimens may vary on a weekly basis: for example, pulsed regimens of vitamin D analogues. And then there may be monthly changes to anaemia therapy following review of biochemical and haematological indices.

It's hardly surprising that patients get confused about their medication!

Drug-induced admissions

But what I find most worrying are situations where drug therapy may be the cause of, or a contributing factor to, an admission. There is a need for more research in the is area. However, one recent study identified drug therapy as the cause of 18% of admissions to a renal unit, with a further 29% of patients having drug-related problems which were identified as capable of contributing to future drug-induced admissions (1).

Within the same population, 27.5% of patients were identified as experiencing a significant drug interaction.

From studies such as this, five main risk factors for drug-related admissions have been described.

		Multiple drug therapies
		Frequent dose adjustments
		Short courses of other drugs being added to regular medication
		Drug therapy incompatible with a patient's lifestyle
		Poor understanding of how to take medication (self-reported non-compliance)

Compliance

While these have been documented as factors which contribute to drug-related admissions, it is clear that they are also issues which contribute to poor compliance.

We face an extensively diverse range of treatments for a population often with a number of co-morbidities, each of which has its own drug-management strategies. It is as a result of a wide range of reasons, including the diversity of patient groups, multiplicity of drug therapies and the potential for drug interactions and adverse effects, that patients have difficulties correctly taking what can become an extensive list of medication.

While complying with medication is part of accepting the overall treatment programme, I'm sure that we are all familiar with the high rates of non-compliance with prescribed medication. This may be through unintentional omission of drugs or intentional non-compliance where, from the patient's perspective, they have a rational reason for omitting some or all of their medication.

This challenge is of particular importance when we consider that non-compliance with prescribed medication remains a major cause for morbidity and mortality within our patient populations.

Many studies suggest between 10-30% of transplant recipients fail to take their medication as prescribed and some studies indicate that 50% are partially non-adherent, whether intentionally or unintentionally, resulting in episodes of rejection and potential transplant loss (2).

While it is hardly surprising that patients can become confused about their medication, they must be provided with a support system through appropriate healthcare professionals.

So, what can we do to improve compliance?

Medication reviews

Perhaps the most practical approach is to make time for review of patients medication through:

		the provision of clear and consistent information that is easily understood -- where necessary as written information in language free from jargon;
		counselling patients, not only in an appropriate environment, but also in an appropriate manner, by the use of careful patient-specific questioning; and
		undertaking this regular review as a specific priority rather than as a side issue during outpatient review, making every effort to fit medication into individuals' lifestyles.

While this way to address non-compliance may sound quite straight forward, it is not easy to achieve. It relies on the rare commodities of an appropriate environment, enough time and the correct approach to each patient.

Medication-review clinics have been found to provide clear benefits to patient care.

One pharmacist-led medication-review clinic has described a reduction in the total amount of medication in 16.3% of patients, with 14.3% of patients changed to a more appropriate drug or preparation (3).

It also discovered that only 11% of patients carried a card detailing their medications.

This particular point raises the whole question of accuracy of medication histories. I have no doubt that if you ask a patient, a community doctor, look in the medical notes, and ask a hospital pharmacist or community pharmacist what their individual records say a patient is taking, you will receive clearly different answers.

Furthermore, there may well be clinically significant differences in the anticipated drug therapy between each healthcare professional.

How can we expect our patients to understand their medication if we cannot provide consistent information?

Until a unified patient record is effectively working and maintained this will remain a considerable limitation. However, until this system is widely available to each healthcare professional involved in patient care the provision of medication cards to patients is the best practical step to address some of the confusion.

Savings to be made

This particular review clinic described by Clare Morlidge identified an annual saving to community drug budgets of £4000 a year (3). While this is a relatively small sum, it is enough to sustain such a service and provide patients with support and education regarding their medication.

But we should take this a step further and consider the financial benefit of avoidance of hospital admissions. A hospital admission may cost at least £250 a day for, say, 10 days -- a total cost of £2500 a patient.

As described by Harchowal, approximately 18% of admissions to a renal unit may be as a result of inappropriate drug therapy (1). Therefore, a saving of £45,000 could be avoided per 100 admissions to a renal unit by such a scheme.

It is studies such as this which demonstrate that continual review of individual patient's medication as a specific priority, not only offers financial advantages, but has also been shown to decrease the risk of drug-related problems and may reduce the incidence of drug-related admissions.

To best manage our patients it is the responsibility of all healthcare professionals to, not only undertake regular review of medication as a specific priority, but also to simplify regimens to fit into patients' lifestyles and provide clear and consistent information that is easily understood.

Perhaps by developing this approach we can improve compliance and associated biochemical and therapeutic responses.