The taskforce for the management of arterial hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC) has recently published the 2013 guidelines for the management of arterial hypertension. 

This publication follows the guidelines jointly issued by both societies in 2003 and 2007 and can be accessed online at www.esh2013.org. This is a lengthy publication running to 60 pages with 735 references; for this reason the reader may wish to view the summary document available at www.escardio.org. Some of the more important points from the new guidelines are highlighted here and reference is made to where they differ from the NICE guideline on hypertension (2011) which can be accessed at www.nice.org.uk. 

Total cardiovascular risk stratification

Decisions on management of the hypertensive patient in the ESH/ESC guidelines depend on the initial level of total cardiovascular disease (CVD) risk. The stratification of total CVD risk in different categories is based on clinic blood pressure level and the presence of CVD risk factors, asymptomatic organ damage, diabetes, symptomatic CVD or chronic kidney disease (see Figure 1). 

The classification in low, moderate, high and very high risk refers to the 10-year risk of CVD mortality, as defined in the 2012 Joint CVD Prevention Guidelines. For further information on this document, see the ICGP quick reference guide, Cardiovascular Disease: Prevention in General Practice, which is available at
www.icgp.ie/go/library. Risk factors include age, male sex, smoking, dyslipidaemia, glucose intolerance, obesity and family history of premature CVD. Asymptomatic organ damage mainly involves left ventricular hypertrophy, evidence of vascular damage and microalbuminuria.

Diagnostic evaluation

While there is a strengthening of the prognostic value of home blood pressure monitoring (HBPM) and of its role for diagnosis and management of hypertension, next to ambulatory blood pressure monitoring (ABPM) in the ESH/ESC guidelines, conventional office BP measurement remains the gold standard for screening, diagnosis and management of hypertension. Hypertension is defined as a systolic BP ≥140mmHg and/or a diastolic BP ≥90 mmHg. The diagnosis of hypertension is still based on at least two BP measurements in the sitting position per visit on at least two visits. Out-of-office BP, assessed by ABPM or HBPM, is stated to be an important adjunct to office BP measurement and that the prediction of CVD events is significantly better with out-of-office BP than with clinic BP. 

However, these guidelines, unlike the current NICE guidelines, stop short of using out-of-office blood BP values in the definition of the different grades of hypertension. Thus, for example in the NICE guideline stage 1, hypertension is defined as being present when clinic blood pressure is 140/90mmHg or higher and the subsequent ABPM daytime average or HBPM average BP is 135/85mmHg or higher. Also, stage 2 hypertension is present when clinic blood pressure is 160/100mmHg or higher and subsequent ABPM daytime average or HBPM average blood pressure is 150/95mmHg or higher. This latter use of out-of-office BP values is very helpful, for example, when drawing up practice protocols for BP management. 

In addition, the fact that a diagnosis is based on an initial clinic visit and a single return visit for out-of-office BP assessment reduces the number of visits to the practice from three to two and enables a diagnosis to be reached more quickly. The levels of out-of-office BP for the definition of hypertension (130/80mmHg for 24-hour BP, 135/85mmHg for daytime ABPM and HBPM and 120/70mmHg for night-time BP) are similar to those used by NICE. 

However, while NICE advocates out-of-office BP measurement for everyone with a clinic BP of 140/90mmHg or greater, the ESH/ESC guidelines give a list of indications for this procedure as follows: suspicion of white-coat, masked or nocturnal hypertension, suspected hypotension, considerable variability of office BP and treatment-resistant hypertension. The ESH/ESC guidelines place emphasis on masked hypertension, which in not referred to at all in the NICE guidelines. Masked hypertension describes a situation where BP may be normal in the clinic and abnormally high on out-of-office measurement. The prevalence of masked hypertension, according to the ESH/ESC guidelines, averages about 13% (range 10-17%). 

Factors which may raise out-of-office BP relative to clinic BP include: younger age, male gender, smoking, alcohol consumption, physical activity, exercise-induced hypertension, anxiety, job stress, obesity, diabetes, chronic kidney disease and family history of hypertension. Also, the prevalence of masked hypertension is reported to be higher when clinic BP is in the high normal range. Masked hypertension appears to be far from harmless, with reports that meta-analyses of prospective studies indicate that the incidence of CVD events is about twice as high than in true normotension and is similar to the incidence in sustained hypertension. 

Given the difficulties we have getting out-of-office BP measurement organised for patients with high clinic BP levels, extending this procedure to the group of normotensive patients listed above would be beyond the capabilities of most general practices in the current economic climate. One suggestion would be to record out-of-office BP only in normotensive patients who have diabetes, chronic kidney disease or family history of hypertension.

Treatment approach

The ESH/ESC guidelines, like NICE, emphasise appropriate lifestyle changes as the cornerstone for the prevention of hypertension and also their importance in its treatment. Prompt initiation of antihypertensive drugs is recommended by the ESH/ESC guidelines in patients at high or very high CVD risk. In addition, they also recommend that antihypertensive drugs should be considered in patients at moderate or low risk when BP remains > 140/90mmHg after, respectively, several weeks or months of appropriate lifestyle measures, or in case of persistently elevated out-of-office BP. 

The NICE guidelines, on the other hand, recommend treatment only after confirming hypertension by ABPM and restricting treatment of patients with stage 1 hypertension (clinic BP 140/90mmHg or higher and daytime average ABPM 135/85mmHg or higher) to those with target organ damage, established CVD, renal disease, diabetes or a high CVD risk (SCORE result indicating a 5% or greater chance of a fatal CVD event in the next 10 years). 

The ESH/ESC guidelines maintain that the advantage of systematically excluding white-coat hypertensives from the possible benefit of treatment remains unproven. They argue that, in this group, waiting increases total risk and that high risk is not always reversible with treatment. The other point they make is that a large number of safe, relatively inexpensive antihypertensive drugs is available and that treatment can be personalised in such a way as to enhance its efficacy and tolerability with a good cost-benefit ratio. However, there is a huge paucity of data for treating stage 1 hypertension, which in turn makes it difficult to give a definitive evidence based guideline on this. 

A welcome recommendation is agreement on a treatment target of 140/90mmHg for all patients except those with diabetes where the target is 140/85mmHg. Treatment targets in the elderly are similar to NICE (patients under 80 years < 140/90mmHg and those over 80 < 150/90mmHg).

Choice of antihypertensive drugs

Unlike NICE, where ACE inhibitors (or angiotensin II receptor blockers) are recommended as first-line treatment for patients under 50 and calcium channel blockers for those over 50, the ESH/ESC guidelines recommend diuretics, beta-blockers, calcium antagonists, ACE inhibitors and angiotensin II receptor blockers as all being suitable for the initiation of antihypertensive treatment. While this distinction generates a good deal of discussion in academic circles (not least at the AGM of the British Hypertension Society annually), GPs will usually end up using a combination of these drugs to treat most of their hypertensive patients.

Conclusion

The ESH/ESC guidelines further emphasise the importance of tackling hypertension in the context of target organ damage and the other CVD risk factors such as smoking and hyperlipidaemia. The problem of masked hypertension is an issue which could ultimately place GPs in an almost impossible position whereby they will have to consider provision of out-of-office blood pressure measurement to a large proportion of normotensive patients at a time when general practice is slowly being starved of resources. 

The ESH/ESC guidelines also recommend that antihypertensive drugs should be considered in all patients at moderate or low risk when BP remains > 140/90mmHg, unlike NICE, where treatment of patients with stage 1 hypertension is restricted to those with target organ damage, established CVD, renal disease, diabetes or a high CVD risk. Furthermore, the ESH/ESC guidelines maintain that the advantage of systematically excluding white-coat hypertensives from the possible benefit of treatment remains unproven. 

Notwithstanding this, many Irish doctors have come to depend on ABPM for the diagnosis and management of hypertension and welcomed the use of out-of-office BP in the staging of hypertension in the NICE guidelines. Ultimately, it is lowering BP that saves lives. It matters little which guideline we use as long as BP control is achieved.