Ireland mustn’t ignore ‘largest epidemic known to mankind’
New US guidelines on high blood pressure recommend aggressive treatment
Cardiovascular disease accounts for about 17 million deaths a year worldwide, with high blood pressure being the major cause.
The new American guidelines for managing high blood pressure have just been published under the lead authorship of an Irish doctor, Paul Whelton. The overall message in the guidelines is that the levels of blood pressure for the diagnosis of hypertension should be lower and that people with high blood pressure should be treated more aggressively to bring their blood pressure levels down to these new low levels.
The guidelines, which are based on the latest scientific evidence from across the world, stress that only by doing so will the increasing havoc being wrought on society due to untreated or poorly treated hypertension – mainly stroke, dementia, heart attack, atrial fibrillation, heart failure and kidney disease – be prevented. Clinical scientists have generally welcomed the recommendations, which are more in tune with European thoughts on hypertension, albeit more assertively so.
The recommendation most likely to affect the day-to-day life of all adults in Ireland is the new definition of hypertension.
Normal blood pressure is presently defined as a systolic blood pressure less than 140 mmHg and a diastolic pressure less that 90 mmHg, whereas the US guidelines advocate normality as a systolic blood pressure less than 120 mmHg and a diastolic pressure less that 80 mmHg, with anyone above these levels being designated as hypertensive. The guidelines also propose more aggressive goals for treatment, urging doctors to prescribe enough blood pressure lowering medication to achieve the new normal levels of blood pressure.
The US guidelines acknowledge and recommend that the most informative and useful of all measurements for the diagnosis of hypertension and for assessing the efficacy of medication is ambulatory blood pressure measurement (ABPM). This technique gives a profile of blood pressure behaviour away from the medical environment as well as providing what may in time prove to be the most important of all measurements – night-time blood pressure.
We, in Ireland, are now faced with the decision to ignore, or to try and implement more than 200 pages of encyclopedic scientific referenced recommendations from the US.
We must not lose sight of the fact that elevated blood pressure is the major global cause of cardiovascular disease which has been dubbed by The Lancet as the “largest epidemic ever known to mankind”, and with good reason. Nearly a billion people have high blood pressure worldwide, and cardiovascular disease accounts for about 17 million deaths a year, with high blood pressure being the major cause, largely by causing heart disease and stroke. It is estimated that the cost of stroke in Ireland exceeds €1 billion per year, with some 10,000 people being affected by what is largely a preventable disease. High blood pressure is the main cause of stroke and in Ireland almost 65 per cent of people aged over 50 years, have high blood pressure (defined by the old levels) with nearly half of these being unaware they have the condition and fewer than 60 per cent are on blood pressure lowering drugs.
Most worrying is the fact that of those on drug treatment, barely half have their blood pressure controlled. So, if the new US guidelines were implemented there would be a substantial improvement in the health and wellbeing of our ageing population.
The US guideline recognises that 24-hour ABPM is the best means of diagnosing and assessing the efficacy of treatment, but warns that of the technique of ABPM will require a major change in practice in America where the technique is used very sparingly and sporadically. However, Ireland is well ahead in this regard in that many general practitioners have been providing ABPM for many years (and this is now reimbursed by the HSE) and many pharmacies also provide the technique.
We should build on this imaginative initiative, which paves the way for beginning to follow the US guidelines, which are based on sound scientific evidence.
If we do so we will be more aggressive in treating hypertension with the aim of obtaining good 24-hour control of blood pressure.
Only by doing so will we will halt the rapidly increasing epidemic of the cardiovascular consequences of undiagnosed and uncontrolled hypertension.
Eoin O’Brien is adjunct professor of molecular pharmacology, The Conway Institute, University College Dublin.