Introduction
Cardiovascular disease remains one of the major causes of morbidity and mortality in the age group 60 years and above in the United Kingdom. Essential hypertension is generally amongst one of the important risk factors for cardiovascular disease, and its prevalence rises progressively with increasing age.¹ In addition, the 'rule of halves'² still applies with hypertensive people. This estimated that about 12.5% of the hypertensive population received adequate blood pressure control. A recent systematic review by the Cochrane Collaboration analysed data from fifteen selected studies which showed that antihypertensive therapy was associated with significant reductions in morbidity and mortality due to stroke, coronary heart disease, all cardiovascular causes, and overall mortality.³ In the UK, it is determined that more than five million elderly people are hypertensive.⁴ However, despite positive advances in hypertension awareness, diagnosis, and management, there has been no reduction in morbidity and mortality. Pharmaceutical care in hypertension clinics in the USA has been well developed.⁵ However, it is uncertain whether this can be translated into a UK model due to differences in the health care system. The aim of this study was to develop a protocol and documentation system to support a pharmacist run hypertensive review clinic.

Methods
A pilot study was conducted in ten general practices in Greater Glasgow health board. The purpose of the pilot study was to develop a protocol and data collecting tools, to establish the likely nature and extent of pharmacist intervention, and to determine the number of patients required for the main study. By using a pharmacist medication review and a hypertension data-collecting form, pharmaceutical outcomes were recorded. Pharmacists were also asked to provide feedback in order to inform the main study.

Results
A protocol was developed including documentation systems. One hundred and thirty two (86%) patients agreed to participate in the pilot study. The pharmacists made a total of 60 referrals regarding hypertension issues to the GPs. Among the recommendations, only 4 per cent were declined by the GPs. A mean systolic blood pressure measured by pharmacists was 147 ± 18 mm Hg. From this it was calculated that a sample of 140 patients were required to achieve a power of 90% at the 1% significance level. It was decided to increase the sample to 260 to take account of the randomised controlled trial design planned for the main study.

Conclusion
The documentation system and protocol underwent minor revisions in the light of comments received. The pharmacists who enrolled on the pilot study were enthusiastic to perform medication reviews and were confident about making the referrals to GPs. A randomised controlled trial consisting of an intervention group and a group receiving current standard care will now form part of the main study.

References

1. MACMAHON, S., et al. Blood pressure, stroke and coronary heart disease. Lancet, 1990, 335, 765-774.
2. SMITH, WC., et al. Control of blood pressure in Scotland. BMJ, 1990, 300, 981-983.
3. MULROW, C., et al. Antihypertensive drug therapy in the elderly (Cochrane Review). The Cochrane Library, oxford: Recent update software 1999.
4. COLHOUN, W., DONG, W., POULTER, N. Blood pressure screening, management, and control in England. J Hypertens, 1998, 16, 747-752.
5. SOLOMON, DK., et al. Clinical and economic outcomes in the hypertension and COPD arms of a multi center outcomes study. J Am Pharm Assoc, 1998, 38, 574-585.