To the Editor: On opening the MJA Focus document “Prevention of cardiovascular disease: an evidence-based clinical aid”,1 I expected to find useful and contemporary guidelines for general practice. However, I was surprised to read two of the recommendations — for the use of antihypertensive and antiplatelet drugs in “low risk” patients (those without risk-associated clinical conditions or end-organ damage).

The document recommends drug treatment only if systolic blood pressure is > 180 mmHg or diastolic blood pressure is > 100 mmHg in people under 60 years, or systolic blood pressure is > 160 mmHg in people over 60 years. While Fulcher et al1 volunteered that this was at odds with clinical practice, they supported the recommendations by stating that they were in accordance with published guidelines. The data for these conservative hypertension parameters were published nearly 10 years ago,2 or derived from textbooks,3 and are at odds with the 1999 WHO/ISH guidelines,4 and even more at odds with the excellent Joint National Committee (JNC 7) report.5 The latter publication recommends, after lifestyle recommendations, drug treatment for a blood pressure of 140–159/90–99 mmHg for those without end-organ damage.

Furthermore, the focus document recommends primary prevention with aspirin in those with a calculated annual cardiovascular event risk > 3%. Hayden et al6 suggest antiplatelet treatment should be offered to those with a 5-year cardiovascular event risk > 3%, which equates to a > 0.6% annual risk. The benefit to harm ratio needs to be explained to the individual, and therapy should only be initiated once blood pressure is controlled.

As an interested general practitioner and user of evidence-based guidelines, I usually check the funding of publications, and, with the heavy emphasis on the use of ACE inhibitors (in particular ramipril) and statins (which are produced by Aventis Pharma), it is difficult to rely on the evidence as presented. I would hope that independent bodies such as the National Prescribing Service or Australian Prescriber could take the pharmaceutical lead and produce desktop references with a more unbiased opinion on the latest collection of evidence that is shaking us up in primary care medicine.

I would again refer readers to the excellent hypertension guidelines mentioned above4,5 (in particular the JNC 7 reference card available on the Internet at www.nhlbi.nih.gov/guidelines/hypertension/jnc7card.htm), and caution them to remain wary of easy-reference desktop items funded by pharmaceutical companies.

In reply: We thank Cradick for his critical review of our publication.1 His interesting points illustrate some of the reasons we were keen to publish this work.

Firstly, the average practitioner is confused about which guidelines (both national and international) to follow. Cradick refers to the JNC 7 report and WHO/ISH guidelines (the committee is familiar with these), but which to follow? The committee decided a priori that Australian national guidelines, if they existed, would be referenced in preference to overseas ones. We mentioned that current Australian hypertension guidelines should be revised, and that clinical practice was probably at odds with these recommendations.

Secondly, guidelines quickly become dated. Cradick cites the recommendation of Hayden et al that aspirin should be introduced if the annual risk of a cardiovascular event is > 0.6%.2 The latest Australian guidelines3 recommending a > 1% annual risk as the treatment threshold were published just after we received Cradick’s letter. The Hayden article is thus (for some patients) at odds with current local recommendations. Consistent with our approach, we will include the Australian recommendations in the first update of our document (July 2004).

Cradick’s comments imply bias in the presentation of the data; yet he fails to substantiate this. Neither the clinical trials quoted (nearly all of which are funded by the pharmaceutical industry) nor the conclusions or inferences drawn have been challenged. He refers to the “heavy” emphasis on the use of ACE inhibitors and statins, implying that this is inappropriate. We would argue that, given the strength of the evidence, this emphasis is appropriate, and reflects current specialist practice in tertiary centres. Careful reading of the National Prescribing Service publications will show that “heavy” reference is made to the 4S,4 LIPID,5 CARE,6 and WOSCOPS7 studies (for example, NPS News 20 February 20028), as well as to the prescribing information for Lipitor (Pfizer), Pravachol (Bristol-Myers Squibb) and Zocor (Merck Sharp & Dohme). We must caution against “throwing the baby out with the bathwater”. The HPS, CARE, LIPID, WOSCOPS, HOPE, PROGRESS, 4S, CURE, and CREDO studies represent substantial and widely acclaimed clinical trials that have had a positive impact on clinical care. They have all been funded by the pharmaceutical industry.

Finally, about 130 GPs in clinical practice had some input in compiling and formatting this document. The document was tested before publication in over 30 000 patients, and was peer reviewed by several clinicians. It is a pity that Cradick was not a participant in any of these processes.