To the Editor: As a long-time resident of the “swamp of uncertainty” which is general practice — where specialists dare not go — I am accustomed to receiving guidelines and consensus statements from esteemed colleagues and friends who have taken to studying some specific part of the human condition. But these statements inevitably involve primary care, where general practitioners try to achieve balance.

Balance is hard to achieve. The “gastro-partialist” thinks that everyone should be on a proton-pump inhibitor. On the other hand, the “osteo-partialist” thinks no-one should be on a proton-pump inhibitor because they stop calcium absorption and double the risk of hip fracture after 10 years. I could go on.

However, here I wish to comment on Heeley and colleagues’ article on the perception and management of cardiovascular disease (CVD) risk in Australian primary care.1

Two of the authors are paid by Servier — the company which provided GPs with free automated blood pressure-measuring machines (ABPMs). A review in the American Journal of Cardiology concluded that no ABPMs were accurate enough to be recommended for replacing a manual sphygmomanometer,2 particularly in older people, in whom vessel stiffness leads to overestimation.3 In the study by Heeley et al, ABPMs were used by 90% of the GPs.

Australia’s Therapeutic guidelines: cardiovascular say that the blood pressure treatment target should be 140/90 mmHg for all patients.4 It quotes the Cochrane review, which states:

Heeley et al have used other guidelines.

Based on the data provided by Heeley et al, about 17% of the patients in their study were aged over 75 years. Risk calculators do not usually go beyond 74 years, but it appears that with all risk factors at optimum levels, a 75-year-old man still has greater than 15% 5-year risk of a cardiovascular event (ie, a high risk). Being 75 years old is risky! Trying to treat a 75-year-old man’s blood pressure is particularly risky because evidence suggests that there is a paradoxical increase in cardiovascular mortality in men aged over 75 years whose blood pressure is lowered by treatment.6

Heeley and colleagues also stated that “two thirds of patients at high risk of a first CVD event were not prescribed a combination of a [blood pressure]-lowering medication and a statin”. Considering the 17% of patients who were older than 75 years, although the PROSPER (Prospective Study of Pravastatin in the Elderly at Risk) trial showed a reduction in cardiovascular mortality within this age group, there was no reduction in overall mortality.7 So why would a GP treat such patients when overall mortality is not reduced?

I imagine that some GPs undertreat because they anticipate poor compliance, because uncorrectable factors are so great that pharmacological interventions will have a miniscule effect, or because the side effects of drug doses needed to achieve guideline targets will be problematic. Maybe they also feel that their ABPMs read a bit high! Balance is an unconscious compromise between real evidence and what is achievable. We need to consider the whole as well as the part if guidelines are to be clinically relevant.

In reply: We thank Radford for his insightful comments, seasoned with spice from the frontline of primary care. Although guidelines are an accepted part of clinical practice, they are just recommendations and are not without their limitations. Treatments need to be individually tailored according to many factors. Our aim, therefore, was to provide a current snapshot of adherence to cardiovascular guidelines in primary care in Australia.1 It would be naive of us to think that there would be complete adherence to the guidelines in the “real world”. We wished to obtain an overall benchmark figure and, more importantly, identify treatment gaps or disparities in care across important patient subgroups defined by risk of cardiovascular event.

We recognise that digital blood pressure (BP) monitors are no better than mercury sphygmomanometers and require frequent (6-monthly) calibration. However, BP measurement technique is a far more important issue. The use of digital BP monitors in our study provided a standardised measurement machine, but we had no influence on their use or on BP measurement technique.

Radford makes a good point regarding the absence of direct randomised trial evidence for the benefit of more intensive BP lowering. The BP target of less than 140/90 mmHg in individuals who are at high risk of a cardiovascular event, such as those with diabetes or chronic renal failure, is a sensible extrapolation from consistent observational epidemiological data. There is, however, convincing evidence of the benefits of multifactorial cardiovascular risk intervention among individuals at high risk.2 We also believe that the available data from randomised trials3,4 provide support for the efficacy of lowering BP in the elderly, and are more robust than the observational data cited by Radford. Similarly, systematic analysis of randomised trials of statin therapy supports efficacy of treatment in older patients.5 Despite their limitations, we believe that current evidence-based recommendations regarding preventive therapies are appropriate guidelines for managing patients who are at risk of a cardiovascular event. As with any guidance for clinical decision making, the application of these recommendations needs to take into account individual patient characteristics and circumstances.

Finally, we believe that Servier’s support for this study demonstrates a successful academia–industry partnership. The academic partners had full control of the study design, analyses and publications.