The most recent edition of Heart Foundation guidelines for the management of hypertension is an evidence-based and practical guide for doctors.1 It is self-evident that clinical guidelines need to be used by doctors if they are to improve population health outcomes. Despite publication of multiple editions of the hypertension guidelines, blood pressure (BP) control in Australia is less than ideal.2 The reasons for this are varied, and include health system, doctor and patient factors.3

Here, I outline simple but effective strategies for addressing some of the doctor factors associated with lack of BP control (Box), based on the Heart Foundation guidelines and supplemented by research conducted in Australian general practice. These strategies should help protect patients from stroke, myocardial infarction and other major organ damage, and are all practical in the general practice setting. Although they will not lead to universal control (because other factors are at play), they should help protect against therapeutic inertia and doctors’ doubts about their own self-efficacy — issues that may adversely affect patient health.

Get blood pressure measurements from a variety of sources. When doctors measure BP, the measurements they record may differ from the true values, because of measurement error, “white coat effect”, poor technique, single measurements, observer error, and data misinterpretation.4 These problems can be addressed, to some degree, in a variety of ways. One approach is to have someone else, or something else, record BP for adult patients. In clinical practice, BP should be measured repeatedly (and preferably by a nurse) — three times, 5 minutes apart, and the last two measurements averaged. The process can be automated with some oscillometric devices, which further reduces bias.4 Away from the practice, the patient can record their BP on a validated,5 regularly serviced machine that they have been taught to use, or they can have their BP recorded by an ambulatory BP monitor. The latter are superior predictors of hard clinical endpoints compared with clinical measurements.6 Specific advice about technique for patients (as well as clinicians) is covered in the chapter of the Heart Foundation guidelines entitled “Measuring blood pressure”.1

Repeated measurements help reduce measurement error and variability, but they need to be interpreted logically. Suitable home BP monitoring can be achieved by asking the patient to measure BP in the morning and evening, to do so twice on each occasion (2 minutes apart after sitting quietly for 5 minutes), and to record the second measurement in a spreadsheet or diary for use at their next appointment. Interpreting the data can be as simple as highlighting elevated measurements, calculating the percentage of elevated systolic and diastolic measurements, or averaging the measurements. The goal is all or nearly all measurements (or average BP) at or below target levels. When interpreting the data, remember that cut-points are lower for recordings made away from the practice; for example, 135/85 mmHg is the cut-point for BP measured away from the practice in patients with uncomplicated hypertension.

Act on absolute risk. In cases where repeated measurements of elevated BP are recorded in at-risk individuals, general practitioners may still not initiate or intensify BP management. Barriers to initiation or adjustment of drug therapy include: clinical uncertainty about underlying true BP and distrust of the technology used to measure BP; distrust of the evidence underpinning the recommendations for management of hypertension; a perceived increased rate of adverse events associated with drug therapy among older patients; perceived patient attitudes towards drug therapy or the need for it; a lack of internal motivation on the part of the practitioner; and health system issues such as lack of time in consultations.

The decision to initiate treatment of elevated BP should not be based on BP alone (unless it is very high). An absolute cardiovascular disease risk score should be used, such as the recently released Australian cardiovascular risk charts, that now include risk for Aboriginal and Torres Strait Islander peoples.7,8 This is a more holistic approach than use of a single risk factor — it integrates all risk factors and thus more accurately identifies at-risk individuals. In primary prevention, population risk calculators are required as doctors cannot reliably estimate absolute risk.9 Patients with mildly elevated BP, who are at low absolute risk, do not require drug therapy but still need action on lifestyle factors that affect BP (eg, alcohol intake, diet, overweight/obesity, and physical inactivity).

Don’t neglect behavioural factors. GPs recognise that behavioural factors underlie elevated BP and mitigate against effective BP control, but may feel that they have limited influence on their patients’ lifestyle. However, brief advice from a GP is the most cost-effective intervention for smoking cessation.10 Also, walking is a simple, free, all-year activity that GPs can recommend. For overweight patients, caloric restriction can be recommended and, for all patients, recommendations that can be considered include moderation of alcohol intake (do not recommend alcohol to non-drinkers), restriction of salt intake (by reading and interpreting processed food labels), and consumption of fruit and vegetables (two serves of fruit and five serves of vegetables per day). Advice should be supplemented with appropriate referrals (eg, to a dietitian).

Accept that most patients will need more than one drug. Most patients will need more than one drug to control their BP.11 This is exacerbated by the need to manage the clustering of risk factors and multiple morbidity, which is common among patients, and especially older patients, with high blood pressure. These factors drive a high evidence-based pill count, which should be distinguished from unnecessary polypharmacy. Thus, the need for two or more drugs to effectively manage hypertension should be communicated to patients from the outset. Follow the guideline recommendations for combinations of drugs.

Ways to deal with the necessary polypharmacy in managing high BP in at-risk individuals include:

• minimising side effects by starting with low doses (especially in older patients and patients with renal impairment), using low-dose combinations, discontinuing ineffective drugs, avoiding agents contraindicated for other conditions that are present, and monitoring for adverse outcomes such as renal impairment;

• minimising cost by using fixed-dose combinations, generics, agents with a larger number of daily doses dispensed, and drugs listed on the Pharmaceutical Benefits Scheme (avoiding “brand premiums”);

• increasing adherence by using combination therapies (especially those that allow within-combination dose adjustments); and

• reducing polypharmacy across morbidities by choosing antihypertensive agents that are indicated for other diseases that are present.

Treat to goal. Once treatment of high BP has been moved to an absolute risk basis, the goals are logically reduced to lower levels for those individuals who are at high absolute risk. For example, the guidelines recommend lower BP targets for increasing levels of proteinuria in patients with chronic kidney disease.1 These patients will require greater individual risk factor reduction to reach low risk than patients who are at intermediate risk. This means more drugs, higher doses, higher costs, and greater difficulty in reaching therapeutic targets.

In cases where the goal is not being reached, assessing for adherence to drug therapy is important — especially during the initiation of drug therapy. Participants in the Second Australian National Blood Pressure Study who answered yes to the question “Did you ever forget to take your medication?” were significantly more likely to experience a cardiovascular event or death than those who answered no.12 Strategies for dealing with necessary polypharmacy will also help reach the goals of target BP and adherence to drug therapy.

The five ways together. Combining these strategies will help to improve BP control via an evidence-based chain of action: obtaining BP measurements systematically, in and away from the general practice setting; stratifying patients according to absolute risk, and acting on risk; considering behavioural measures for all patients; and utilising drugs (usually two or more) for patients who are at high risk, to reach recommended, targeted goals.