Intended for healthcare professionals

Rapid response to:

Analysis Too Much Medicine

Mild hypertension in people at low risk

BMJ 2014; 349 doi: https://doi.org/10.1136/bmj.g5432 (Published 14 September 2014) Cite this as: BMJ 2014;349:g5432

Rapid Response:

In the growing series of over-hyped, over-diagnosed conditions we can discern a pattern, even a paradigm.. DISEASE – SCREENING – FACTORS – RISK - MODIFIERS

In the case of ‘hypertension’, it began with a clinically recognisable DISEASE called ‘malignant hypertension’. We quickly learned that you were dead in six months if you didn’t start drug treatment. This gave rise to the desire to ‘screen’ for it in the hope of earlier diagnosis. By measuring a parameter such as blood pressure, rather than a disease, we entered a realm of statistical sampling. Dismissing Pickering’s warnings, we then defined a crude subset to be ‘mild hypertension’. We were wise to conduct randomised controlled trials of treatment, but seemed not to have examined the results closely enough. Instead our disease-oriented mindset was persuaded by pharmaceutical purveyors into 50 years of overtreatment, well beyond the few with ‘malignant’ disease. Martin et al demonstrate nothing that we was not already available to be recognised last century.

A similar behaviour pattern occurred when the parameter was cholesterol. But we were discerning enough to note that ‘hypercholesterolaemia’ was not really a disease (unless perhaps it was familial) and cholesterol-lowering treatments were often unpalatable or harmful. The battle against ‘cholesterol’ per se was losing. Then came Simvastatin – highly effective in 4S if you had suffered a heart attack. Trials quickly followed showing that the drug worked, regardless of your initial cholesterol, or LDL. What mattered was ‘CVD RISK’. That was the ‘paradigm-shift’ - an increasing understanding that a composite of multiple risk factors determined your absolute chances of a stroke or heart attack. Risk-factor treatments exposed everyone to potential side-effects, whilst those with most to gain were those most at risk. Having already suffered a heart attack, you are automatically recognised as high-risk. Age, sex, Diabetes and FH add in, and then come the modifiable parameters.

What Martin et al. need logically to do now is drop the term ‘mild hypertension’. Instead we need to assess ‘CVD Risk’ as a unifying paradigm determining who stands to gain, by which intervention, and by how much. RCTs have shown that people who have had CVD events, or have Diabetes are likely to gain by lowering BP maybe down to 130/80. Other RCTs show that men with BP of 150/90 and low CVD risk do not benefit from drug treatment, whilst healthy women, for example, with no ‘disease’ and low CVD risk do not benefit at all unless their BP is very much higher.

Competing interests: No competing interests

21 September 2014
L Sam Lewis
retired GP
NHS
Surgery, Newport,pembrokeshire, SA42 0TJ