Hypertension-Malaysian CPG

Hypertension is defined as persistent elevation of systolic BP of

140 mmHg or greater and/or diastolic BP of 90 mmHg or greater.

The classification is based on the average of two or more readings

taken at two or more visits to the doctor. When SBP and DBP fall

into different categories, the higher category should be selected to

classify the individual’s BP.

Definition of prehypertension

Prehypertension is defined as systolic BP (SBP) 120 to 139 or

diastolic BP (DBP) 80 to 89 mmHg, based on 2 or more properly

measured seated BP readings on each of 2 or more office visits.

If BP is still >140/90 mmHg with three drugs, including a

diuretic at near maximal doses, patients by definition have

resistant hypertension.

Efforts must be made to reach target BP. For patients <65 years old, the

target BP should be <140/85 mmHg and <130/80 mmHg for

diabetics.In general once the BP is controlled, most patients will require life-long

treatment.

SEVERE HYPERTENSION

Definition:

Severe hypertension is defined as BP >180/110 mmHg.

These patients may present in the following manner:

• incidental finding in an asymptomatic patient

• non-specific symptoms like headache, dizziness, lethargy

• symptoms and signs of acute target organ damage. These

include acute heart failure, acute coronary syndromes, acute

renal failure, dissecting aneurysm, hypertensive encephalopathy

and stroke

Patients are then categorised as having:

a) asymptomatic severe hypertension,

b) hypertensive urgencies, or

c) hypertensive emergencies

(b) and (c) are also referred to as hypertensive crises.

Asymptomatic severe hypertension:

Admission may be necessary in the newly diagnosed, or where

compliance may be a problem. Patients already on treatment need

to have their drug regime reviewed.

Hypertensive urgencies:

-These include patients with grade III or IV retinal changes (also

known as accelerated and malignant hypertension respectively), but

no overt organ failure. These patients may need admission.

-BP measurement should be repeated after 30 minutes of bed rest.

Grade 1

Generalised arteriolar constriction - seen as `silver wiring` and Vascular tortuosities.

Grade 2

As grade 1 + irregularly located, tight constrictions - Known as `AV nicking` or `AV Nipping`

Grade 3

As grade 2 + with cotton wool spots and flame-haemorrhages

Grade 4

As above but with swelling of the optic disk (papillodema)

There is an association between the grade of retinopathy and mortality. At 3 years 70% of those with grade 1 retinopathy will be alive whereas only 6% of those with grade 4 will survive.^[1]Grading of the retinopathy is thus important as the hypertensive process will be affecting small vessels throughout the body in a similar manner. (The retina is simply the most visible area to assess.)

-Initial treatment should aim for about 25% reduction in BP over 24 hours

but not lower than 160/90 mmHg. (Level III)

- Oral drugs proven to be

effective are outlined in Table 10. Combination therapy is often

necessary.

Hypertensive emergencies:

-These include patients with complications of severe hy

pertension

such as acute heart failure, dissecting aneurysm, acute coronary

syndromes, hypertensive encephalopathy, subarachnoid

haemorrhage and acute renal failure.

-These may occur in patients with BP <180/110 mmHg, particularly if the BP has risen rapidly.

-All these patients should be admitted.

-The BP needs to be reduced rapidly. It is suggested that the BP

be reduced by 25% depending on clinical scenario over 3 to 12 hours but not lower than 160/90 mmHg

-This is best achieved with parenteral drugs.

Dangers of rapid reduction in blood pressure:

Rapid reduction of BP (within minutes to hours) in asymptomatic

severe hypertension or hypertensive urgencies is best avoided as

it may precipitate ischaemic events.