Hypertension

Introduction

Hypertension (or high blood pressure) is a silent disease; in 2015, for every 2 diagnosed patients in Malaysia, there are 3 undiagnosed patients.

  • Most people with hypertension are unaware of the problem because it may have no warning signs or symptoms.
  • When symptoms do occur, they can include early morning headaches, nosebleeds, irregular heart rhythms, vision changes, and buzzing in the ears.
  • Severe hypertension can cause fatigue, nausea, vomiting, confusion, anxiety, chest pain, and muscle tremors.

Untreated or sub-optimally controlled hypertension leads to increased cardiovascular, cerebrovascular and renal morbidity/mortality and overall mortality.



Definition

Hypertension is most commonly defined as persistent elevation of systolic BP of 140 mm Hg or greater and/or diastolic BP of 90 mm Hg or greater. However, definition vary by professional organization.

Diagnostic Considerations for Hypertension

Diagnostic Considerations for Hypertension

NOTE: For stage 1 hypertension (SBP 130-139 mm Hg or DBP 80-89 mm Hg) in patients with estimated 10-year ASCVD risk <10%, ACC/AHA 2017 guideline only suggest to use nonpharmacologic therapy and repeat BP evaluation within 3-6 monthly.

Isolated office ("white-coat") hypertension is characterized by an elevation in clinic BP (persistently above 140/90 mm Hg) but normal home or ambulatory BP values (lower than 135/85 mm Hg).



Risk Stratification

Many patients with hypertension have more than one other cardiovascular risk factor.

  • Each additional risk factor increases cardiovascular risk substantially.
  • Hence, overall global cardiovascular risk of a patient with hypertension should be done.

There are various ways to assess global cardiovascular risk and this includes using validated risk charts like the Framingham General Cardiovascular Risk Chart which has been validated locally and found to perform quite well or using risk stratification tables which stratifies the risk of developing major cardiovascular events, which includes stroke, myocardial infarction and total mortality.

Risk Stratification of Hypertension

NOTE: Try to deduct a summary from the table above on when you may suggest lifestyle intervention only.



Non-Pharmacological Management

Achieve a weight loss of as little as 1 kg from baseline to reduce BP by 1 mm Hg SBP.

Reduce salt intake to <2 g of sodium or <5 g of salt a day (equivalent to 1 teaspoonful of salt).

Refrain from alcohol intake. Advise patient who insists to continue drinking to consume ≤ two drinks per day.

Advise patients to perform physical activity (e.g. moderate intensity aerobic exercise of at least 150 minutes per week).

Encourage diet rich in fruits, vegetables, and dairy products with reduced saturated and total fat.

Stop smoking to reduce overall cardiovascular risk.

Encourage patient to manage stress although evidence on relaxation interventions have not been convincing. Yoga had been shown in a systematic review to reduce BP by 4.2/3.6 mm Hg but the quality of evidence is poor.



Drug Management

In patients with newly diagnosed, uncomplicated hypertension and no compelling indications, choice of first line monotherapy includes ACEIs, ARBs, CCBs and diuretics.

  • Beta blockers are no longer recommended as first-line therapy in patients with uncomplicated elevated blood pressure because they are less effective than the first-line drugs in reducing the risk of stroke. However, they have a clear place in the management of patients with heart failure with reduced ejection fraction (HFrEF) and patients with coronary artery disease.

If after a sufficient period of treatment (up to 6 weeks) with monotherapy, BP is still not controlled, three options are available:

  • The dose of the initial drug can be increased
  • The drug can be substituted with another class of drug
  • A second drug can be added

Combination therapy is often required to achieve target and may be instituted early in patients with stage II hypertension and in high risk stage I hypertension.

  • Fixed-dose combinations, also known as single-pill combinations, which incorporate two antihypertensive drugs or more into one pill, can improve control rates without increasing the risk of adverse events, and can thereby prevent millions of heart attacks, strokes, and other complications of uncontrolled hypertension.
  • Adding a low dose of a second drug from a different class is usually more effective than increasing the dose of the initial drug.

Choice of Antihypertensive Drugs in Patients with Concomitant Conditions



BP Treatment Target

BP Treatment Target as per Clinical Practice Guideline on Management of Hypertension, 2018

  • Treat BP to SBP <140 mm Hg and DBP <90 mm Hg for most hypertensive patients
    • CKD Patients with proteinuria of <1 g/24 hour
    • Patients with concurrent IHD, peripheral arterial disease (PAD), PAD with/without AF
    • Primary and secondary prevention of stroke
  • Treat SBP to < 130 mm Hg and DBP <80 mm Hg for high/very high risk patients
    • CKD Patients with proteinuria of >1 g/24 hour
    • Patients with Left Ventricular Hypertrophy (LVH)
    • Secondary prevention in lacunar stroke

NOTE:

  • Hypertension and Diabetes Mellitus
    • The presence of microalbuminuria or overt proteinuria should be treated even if the BP is <140/90 mm Hg. An ACEI or ARB is preferred.
    • Aim for BP in the diabetic to be <140/80 mm Hg
    • Consider to lower BP <130/80 mm Hg in younger patients
  • Hypertension in the Older Adults
    • Target BP <150/90 mm Hg for >80 years old
    • Target SBP <140/90 mm Hg for 65-80 years old
    • Consider SBP <130/80 mm Hg in fit 65-80 years old
    • Apply less strict targets for the frail, functionally and/or cognitively-impaired, those with multi-morbidities and those with adverse reactions from therapy.



Resistant Hypertension

Resistant hypertension is defined by a patient whose BP is not controlled on three or more drugs (including a diuretic).

After excluding medication non-adherence and isolated office hypertension, a quick check on the possible causes of resistant is required.

  • Secondary hypertension
  • Excessive sodium intake, excessive liquorice intake, drugs and drug interactions
  • Complications of long standing hypertension such as nephrosclerosis, loss of aortic distensibility and atherosclerotic renal artery stenosis



Step-Down Therapy

One question that I often have from patients: is the antihypertensive drugs going to be life-long?

In the vast majority of patients, step-down therapy is discouraged. However, in patients who insist on it, the following criteria must be considered first:

  • Patients' BP must not be higher than stage I (mild) hypertension with low global CV risk
  • BP well-controlled for at least 1 year on the same medication at the same dosage
  • Must agree to be followed up at least 3-6 monthly
  • Must be motivated to adopt healthy living



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