The European Society of Cardiology (ESC) and the European Society of Hypertension (ESH) have updated their previous 2003 and 2007 guidelines on the management of arterial hypertension; Their renewed joint efforts have produced new guidelines supported by recent scientific evidence from numerous studies and published reports of clinical experience in hypertensive patients (1-2).
This review delineates the points formulated. Hopefully clinicians will be able to judge their weight and decide on the changes to make in their daily activity with patients.
I - Approaching hypertension
1 - Diagnosis: values and measurements
The value of 140/90 mm Hg in the office, although arbitrary, is confirmed as a dividing line between normal and elevated pressures: “Hypertension is defined as values >140 mmHg SBP and/or > 90 mmHg DBP”.
Nevertheless, the guidelines follow through with previous recommendations which were that figures obtained by more modern, mostly automatic techniques for blood pressure recording - ambulatory or home, but also automated techniques- , help modulate the impact of office blood pressure largely as far as consequences are concerned.
Authors insist that to optimise office blood pressure measurements, these should be recorded repeatedly, i.e. within each consultation and at every consultation.
Similarly, with each new patient measurements should be taken on both arms and when it comes to elderly patients, standing blood pressure is suggested strongly.
Furthermore, as it has been known for over a decade, it is reminded that the study of ambulatory and home recordings offer these interesting insights: 1) a better correlation between ambulatory blood pressure and cardiovascular events both in treated and in non-treated hypertensive patients than with twenty-four hour recordings (3); 2) night-time blood pressure elevation is accompanied by worse prognosis; 3) there are more and more arguments (which we will go into further in this review) that white coat hypertension, originally seen as innocent, may carry a stronger impact on prognosis than expected; Finally, 4) masked hypertension is generally accepted as increase risk.
Nevertheless tt is observed that twenty-four hour recordings are often replaced by home recordings; these recordings are taken during the "normal” life conditions of the patients and can be made over a longer period (usually a week). However, it must be noted that home recordings do not yield night values and can sometimes elicit panic reactions in sensitive patients.
2 - Prevalence and association with risk factors
The guidelines recognise that the prevalence of hypertension is underestimated. In the Western world, figures of 25-35% (or more) of hypertension in adults are given. However, such figures are obtained by studies carried out in small samples of the population. It is also worth mentioning that there is a slight trend for a decrease in Western Europe while there is an increase of hypertension in Eastern Europe. Furthermore the well known high prevalence of elevated systolic blood pressure in elderly people, is a sizable problem that is associated with disabling events in the future, both on a personal scale and for society as a whole.
Increased risk of hypertension is not only due to the elevated pressure “per se”; it also is caused by the concomitant presence of other risk factors. In this respect the importance of obesity and diabetes associated with elevated pressure is underlined in the guidelines.
Moreover, even mild hypertension can become a serious concern whenever it is associated with other risk factors; such a condition is misleading and often underestimated. Thus, the guidelines clearly state that global estimation of total cardiovascular risk should be made in every hypertensive patient.
3 - Investigations
The investigations that should be done in every “new” hypertensive patient are:
- Most essential, the technically correct and repeated office pressure measurements.
- Regular risk factors to be examined such as blood cholesterol, blood glucose, body weight and nicotine use.
- Information on kidney function to be taken - including microalbuminuria and electrolytes such as serum sodium and potassium.
- An electrocardiogram is useful to invalidate the impact of elevated pressure on the heart; an echocardiogram only is needed when visualisation of the cardiac structures and function are necessary.
- Ambulatory blood pressure recordings are recommended in patients with large variations in pressure, and cases when white coat or masked hypertension is suspected. Ambulatory bolood pressure recordings are also recommended whenever there is contradiction in the findings such as repeated high blood pressure in the office without left ventricle hypertrophy or vice versa.
- Resistant hypertension (see further) is also a good indication for prolonged recordings.
II - Managing hypertension
1 - Lifestyle modifications and drug treatment
Much attention is devoted to lifestyle modification - including eating habits - in these new guidelines. Changes in lifestyle can be most helpful in controlling risk factors; several studies have shown that these can decrease blood pressure almost as much as monotherapy.
Indeed, weight control is another very important issue, especially in light of what is called the obesity “epidemic” in the Western world. Decreasing sugar in drinks and controlling saturated and trans fatty acid intake is important advice. Regular physical exercise should be stimulated not only focusing on high level performances but also on regular even more limited exercise like daily walking (even 30 minutes walking can help control blood pressure).
The guidelines continue to underline the importance of salt decrease: if intake goes down from the usual 10 grams, a day, to 5g, the guidelines state, SBP-lowering effect in normotensive individuals and a somewhat more pronounced effect (4–5mmHg) in hypertensive individuals.
Indeed, eighty per cent % of salt consumption involves ‘hidden salt (for a look at how to quantify salt intake in certain patients, look at this edition of the e-journal). Although fermentation requires both yeast and salt, the salt contained in bread is unnecessarily high, – a target of less than 1 gram per 100 grams of bread is being followed in a number of European countries but this is, by far, still not a general rule.
Pharmacological treatment of hypertension takes up a large portion of the document. A first general remark is that lifestyle adaptation and drug treatment should be started as soon as possible after detection of elevated blood pressure; they can be initiated together instead of what is done today. This is particularly the case in patients with high total risk, even if blood pressure values are not very high.
How to manage patients with mild/moderate hypertension and low total risk is discussed at length. It is suggested to perform ambulatory recordings in such patients; in cases where the results fall within normal limits all attention should be given to lifestyle adaptation and control of body weight and salt intake. A similar question is in respect to elderly patients with a systolic pressure above 160 mm Hg. The answer here is that antihypertensive drugs should be considered in case lifestyle adaptation does not produce the satisfactory results; at lower levels of pressure, non-drug treatment should be preferred.
2 - Target blood pressure and choice of drugs
Target pressure remains clearly set at 140/90 mm Hg. In diabetics, the target value is set at 140/85 mm Hg.
In the reappraisal document of 2009 (4), it had been mentioned that in diabetic patients a figure of 130/80 mm Hg should be used as reference; however, objective and careful analysis of published data do not provide us with objective, well proven information whether this lower value indeed should be used in practice. The proposal of the lower target value clearly had come from the general adagio “the lower, the better” but solid proof for getting as low as 130/80 is largely lacking or at least incomplete. Similarly, there is a clear change of opinion concerning the “J-curve” , a concept that was largely denied at the end of the previous century but seems to come up again as a reality. Such changes in opinion might suggest that the value of blood pressure decrease in hypertensive patients is considered less important in actual science; this is clearly not the case! All attention should be focused to the insufficient control of blood pressure in these patients as target pressure very often, is not obtained !
The guidelines underline that the difference in blood pressure lowering effect between on antihypertensive drug or the other is relatively small; also it is suggested to more often use a combination of drugs; the choice between drugs is considered much more dependent on the individual characteristics of the patient and the individual response to the drug; moreover, a lot of the eventual differences between the drugs is fading away from using combination therapy.
Last year, some efforts had been devoted to comparing different diuretics; the authors of the guidelines seem not too impressed by such considerations but accept that the response of the individual patients can differ a lot and this also is true in respect to quality of life.
Some other points are clarified in the text. There is no argument set forth that antihypertensive drugs could set on a process leading to cancer.
Beta-blocking agents still have a place in the treatment of hypertension, especially in patients with coronary artery disease.
In high risk patients, it is suggested to start with combination of drugs as first choice. A clear schedule for starting with antihypertensive drugs is given in the text (1-2).
Most possibilities for combination of drugs are acceptable. There is some reservation regarding the combination of beta blockers and diuretics because of their possible influence as far as onset of diabetes. A much stricter reservation exists in respect to combination of an ACE and a Sartan; this type of combination is considered to be linked to more events (see Ontarget study).
In patients with a recent cerebrovascular accident it is prudent to decrease high blood pressure slowly; possibly a calcium antagonist could be preferred but the arguments are not very solid.
3 - Resistant hypertension and the remaining unresolved problem
Considerable attention has been devoted in the last few years to elevated blood pressure resistant to treatment (for how to identify and manage resistant hypertension go here).
The definition of resistant hypertension, however, remains unchanged: it is when blood pressure figures are repeatedly above 140/90 mm Hg on treatment with three antihypertensive drugs, including a diuretic. In such cases It is suggested to check 1) the patient’s compliance to treatment and then check 2) blood pressure using ambulatory techniques. A strict control of risk factors is absolutely necessary.
In the majority of cases, it is clear that such blood pressure is not really resistant and that only a small group (10-15%) of the cases are in agreement with the definition of resistant hypertension as given above. In this small group of patients, it is indicated to first try a small dose of an aldosterone antagonist, at low doses. In case there still is no satisfactory response, denervation of the renal sympathetic nerves can be a solution.
Renal denervation yields good results in many patients, although not in all. For a look at a previous e-journal article on catheter-based renal denervation, see here. Positive results concern both blood pressure control and side effects. However, long term results are still awaited. Therefore, the guidelines, although clearly accepting of these encouraging results, suggests to look for confirmation before considering widespread use; also it is suggested to restrict the application of the technique to centres fully equipped to perform the denervation and to manage eventual unexpected consequences.
All evidence has shown that at least from a scientific point of view, the management of hypertension is, in theory, largely no longer a problem. Still, many well performed population studies clearly demonstrate that in practice, high blood pressure in the population is still not under control! Causes for such surprising negative findings are multiple. First, compliance to antihypertensive therapy is poor; then, hypertensive patients tend to not fully understand what their problem is - especially the notion that their condition requires lifelong treatment and attention. Further, the medical world is still not focusing enough on the follow-up of treated hypertensive patients with objective blood pressure measurement techniques. Hopefully, politicians can be involved to help us solve this worldwide problem carrying many medical, social and financial consequences.
The 2013 guidelines have succeeded to renew the focus on the problem of hypertension in the Western world:
- Objective and repeated control of blood pressure and risk factors is absolutely necessary.
- Modification of lifestyle and eating habits need urgent application.
- In respect to drug treatment, combination therapy should be used earlier in management.
- Interruption of renal nerve traffic is bringing encouraging results.
However, on top of all of these recommendations, ample information has indicated that blood pressure in the population is insufficiently controlled; therefore, a clear strategy for continued and objective follow-up should be instituted.
For specifically the new aspects of the guidelines, see here Prof Michal Tendera and Prof Thierry Gillebert's viewpoints and ther is also a webcast available from guidelines authors R. Fagard and G. Mancia: Arterial hypertension (joint ESC/ESH) 2013 and Arterial hypertension: questions and answers to the panellists 2013.