Prescribing Advice for GPs

Statins

August 24, 2005 on 12:13 pm | In Prescribing Formulary |  Print | 1 Comment

A recommendation has already been made regarding changing statin therapy following the implementation of the new Pharmacy Contract.

There is much discussion at present about the likely changes to the GMS contract and the targets contained within it regarding cholesterol. Broadly speaking there are two sides to the argument, the “fire and forget” approach and the “treat to target” approach. The treat to target approach is firmly contained in the current contract and rumours abound that the target is likely to be lowered for next year. The evidence to support this approach is growing but as yet is not entirely persuasive.

It would be prudent in any eventually to take a stepped approach to treatment to ensure that whatever happens, prescribers are prepared to tailor treatments to gain maximum benefit for as many patients as possible. Using the most cost effective and evidence based statins as first line will help to achieve this goal.

The 4S¹ and HPS² studies have shown that Simvastatin is an effective and well tolerated drug. It reduces cholesterol by 30% at the 40mg strength and has evidence to prove its benefits in saving patients lives. Simvastatin is unprecedented as the choice for lipid lowering.

In situation where Simvastatin 40mg does not get the patient to the required target, first consider if the patient is taking the medication and if they are still eating a healthy diet before altering the treatment. Where a treatment alteration is required, Atorvastatin 40mg is a more potent cholesterol reducing agent albeit with a lower level of evidence in terms of cardiovascular event outcomes.

Finally, if Atorvastatin 40mg fails to attain prescribers should consider the most appropriate way forward for the patient in question. Options include accepting the current cholesterol level, increasing the dose of the statin, adding in another lipid lowering agent or referring to a specialist.

Action: Implement and use a stepped approach to lipid management as follows:

• Simvastatin 40mg tablets, 1 each day
• Atorvastatin 40mg tablets, 1 each day
• Revert to Simvastatin 40mg tablets and add Ezetimibe 10mg tablets, 1 each day
  
  Or Increase to Atorvastatin 80mg tablets, 1 each day
  
  Or Refer for specialist advice

References

1. The Scandinavian Simvastatin Survival Study Group. Randomized Trial of cholesterol lowering in 4444 patients with coronary heart disease. Lancet 1994;344:1383-1389
2. Heart Protection Study Collaborative Group. MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20,536 high risk individuals: a randomised placebo-controlled trial. Lancet 2002; 360: 7-22M

Antiplatelets

August 24, 2005 on 11:34 am | In Prescribing Formulary |  Print | No Comments

Antiplatelets should be prescribed to reduce the risk of a cardiovascular event. This risk reduction can be classified as primary or secondary prevention depending on whether the first or subsequent event is being prevented. The evidence for the most appropriate intervention differs between these two groups.

Secondary Prevention is the reduction of risk of a subsequent cardiovascular event, for example a heart attack or stroke. NICE have recently issued a Technology Appraisal on this topic.

The guidance states the following:

• Low dose Aspirin (75mg [Dispersible]) is “standard care”
• In patients who have had an ischaemic stroke or a transient ischaemic attack, the combination of modified-release dipyridamole and aspirin (Asasantin) is recommended for two years after the most recent event
• Only in patients who are intolerant to aspirin should clopidogrel (Plavix) be used (within the product license)

Primary Prevention is the reduction of risk of a first event. The NICE Technology Appraisal detailed above does not cover this population. In this group of patients the expected risk reducing benefits must be weighed against the potential risks associated with the treatment. It is also important to pay due regard to product licenses. Neither Asasantin nor Plavix are licensed for Primary Prevention.

An article on Bandolier has provided a sensible and evidenced approach to balancing the risks and benefits. This article concludes that at a coronary risk of 1.5% per year (or 15% in 10 years, or a CVD risk of 20% in 10 years) the benefits outweigh the risks.

Patients who are at a greater than 20% risk of their first CVD event in the next 10 years should be offered antiplatelet therapy with Low Dose Aspirin (provided their blood pressure is controlled and there are no contraindication)

Action: Prescribers should use Aspirin 75mg Dispersible as first line treatment for prevention of cardiovascular events. Where compliance is to be affected by gastrointestinal symptoms an Enteric Coated formulation can be tried before the alternative strategies listed above.