bpj-sce-august-2020

CARDIOVASCULAR SYSTEM
NEPHROLOGY
Hypertension in adults: the silent killer
Hypertension is associated with a wide range of cardiovascular and end-organ damage and is one of the most
frequent reasons for patient attendance in primary care. The ideal treatment of hypertension continues to
be debated. However, management often requires multiple medicines to achieve blood pressure targets and
reduce overall cardiovascular risk, alongside lifestyle changes.
KEY PRACTICE POINTS:
Five-year cardiovascular disease (CVD) risk should be
calculated using NZ primary prevention equations in all
patients with a blood pressure (BP) consistently ≥130/80
mmHg to guide decisions regarding antihypertensive
treatment
Angiotensin-converting enzyme (ACE) inhibitors or
angiotensin II receptor blockers (ARB), calcium channel
blockers and thiazide(-like) diuretics are all first-line
antihypertensives
– Beta-blockers are no longer first-line unless indicated
Guidelines recommend low-dose dual antihypertensive
treatment (as opposed to monotherapy) initially unless a
patient is within 20/10 mmHg of their BP target, aged ≥ 80
years, frail, or committing to major lifestyle changes
BP targets should be individualised according to the
patient’s CVD risk, co-morbidities and treatment objectives
For patients not achieving targets despite dual
antihypertensive treatment, adherence should be assessed,
and a third antihypertensive considered, or doses can
be increased if the patient is close to their BP target;
spironolactone or other medicines (e.g. beta- or alphablockers)
should then be added if triple antihypertensive
treatment has not reduced BP to target levels
Hypertension is a continuum requiring
regular review
Hypertension is a risk factor for many conditions including
stroke, myocardial infarction, heart failure, atrial fibrillation,
kidney disease and cognitive decline. 1 It is described as a silent
killer because it is insidious, chronic and progressive. 2
International guidelines vary in the thresholds used
to define hypertension. Although it has previously been
common practice in New Zealand to consider any clinic BP
≥140/90 mmHg as being “hypertensive”, BP measurements
alone are insufficient to define and guide the management
of hypertension in primary care. 3 BP has a normal distribution
across the general population and the cardiovascular disease
(CVD) risk associated with increasing measurements is
continuous. 4 If additional factors are present that elevate
CVD risk further, a patient is more likely to experience a
cardiovascular event, even if their BP is within the “high normal”
range, i.e. 130–139/85–89 mmHg: 1, 4
Risk factors include: being aged ≥65 years, male sex,
increased heart rate (>80 beats/min), excess body weight,
diabetes, high LDL-C/triglycerides, a personal or family
history of CVD or hypertension, early onset menopause,
smoking, and psychosocial or socioeconomic factors
18 Best Practice Journal – SCE Issue 1 www.bpac.org.nz