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A Guide to Hypertension Management
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| Hypertension:
Definition |
Hypertension
is defined as a sustained increase in systolic BP (SBP) of 140
mmHg or greater and/or diastolic BP (DBP) of 90 mmHg or greater.
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| Classification
of blood pressure (1999 WHO/ISH guidelines) |
| Category |
Systolic |
Diastolic |
| Optimal |
<120 |
<80 |
| Normal |
<130 |
<85 |
| High-Normal |
130-139 |
85-89 |
| Grade
1 Hypertension (Mild) |
140-159 |
90-99 |
| Grade
2 Hypertension (Moderate) |
160-179 |
100-109 |
| Grade
3 Hypertension (Severe) |
>180 |
>110 |
| Isolated
systolic hypertension (ISH) |
>140 |
<90 |
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| Types
of hypertension |
- Primary or Essential hypertension
(No underlying cause)
- Secondary hypertension (Hypertension
due to kidney disease, vascular or endocrine disorders)
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| Hypertension:
Predisposing factors |
- Age >60
- Sex (Men and postmenopausal
women)
- Family history of cardiovascular
disease
- Smoking
- High cholesterol diet
- Co-existing disorders such
as diabetes, obesity and hyperlipidaemia (elevated cholesterol
levels)
- High intake of alcohol
- Less active life style
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| Major
complications of untreated hypertension |
- Myocardial infarction
- Stroke
- Renal failure
- Retinopathy
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| Management
of hypertension |
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| Life
style modifications |
- Lose weight, if overweight
- Limit alcohol intake
- Increase physical activity
- Reduce salt intake
- Stop smoking
- Limit intake of foods rich
in fats and cholesterol
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| Drug
therapy for hypertension |
| Considerations
for initiating drug therapy |
- For most patients, a low dose
of drug should be used. Dosage can be increased based on
patient’s response to initial therapy
- Drugs providing longer duration
of action, i.e. 24 hours (once-daily), should be preferred
due to
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- Smooth and sustained control
of blood pressure
- Enhanced patient compliance
(less likelihood of patients missing out on dose)
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| Available
drug options |
| Class
of drug |
Example |
Initiating
dose |
Usual
maintenance dose |
| Diuretics |
Hydrochlorothiazide |
12.5
mg once daily |
12.5
mg -25 mg once daily |
| Beta-blockers |
Atenolol |
25
mg-50 mg once daily |
50
mg-100 mg once daily |
| Calcium
channel blockers |
Amlodipine |
2.5
mg-5 mg once daily |
5
mg-10 mg once daily |
| Beta-blockers |
Doxazosin |
1
mg once daily |
1
mg-8 mg once daily |
| ACE-inhibitors |
Lisinopril |
2.5
mg-5 mg once daily |
5
mg-20 mg once daily |
| Angiotension-II
receptor blockers |
Losartan |
25
mg-50 mg once daily |
50
mg-100 mg once daily |
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| Choosing
the appropriate antihypertensive |
- Hypertension not associated
with any co-existing conditions
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A drug from any of the above
six classes may be selected |
- Hypertension with co-existing
condition.
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| Condition |
Preferred
drugs |
Other
drugs that can be used |
Drugs
to be avoided |
| Asthma |
Calcium
channel blockers |
Alpha-blockers/
Angiotensin-II receptor blockers/ Diuretics/ACE-inhibitors |
Beta-blockers |
| Diabetes
mellitus |
Alpha-blockers/
ACE-inhibitors/ Angiotension-II receptor blockers |
Calcium
channel blockers |
Diuretics/
Beta-blockers |
| High
cholesterol levels |
Alpha-blockers |
ACE-inhibitors/Angiotensin-II
receptor blockers/ Calcium channnel blockers |
Beta-blockers/
Diuretics |
| Elderly
patients (above 60 years of age) |
Calcium
channel blockers/ Diuretics |
Beta-blockers/ACE-inhibitors/
Angiotension-II receptor blockers/Alpha-blockers |
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| BPH |
Alpha-blockers |
Beta-blockers/
ACE-inhibitors/ Angiotensin-II receptor blockers/ Diuretics/Calcium
channel blockers |
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| Combination
therapy for hypertension recommended by JNC-VI guidelines and
1999 WHO-ISH guidelines |
| With
any single drug, not more than 25-50% of hypertensives achieve
adequate blood pressure control. |
|
Journal of Hum. Hypertens 1995;9:S33-S36
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| Combination
therapy controls blood pressure in a greater number of patients
than any single drug used alone. |
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Journal of Hum. Hypertens 1995;9:S33-S36
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| Advantages
of fixed-dose combination therapy |
- Better blood pressure control
- Lesser side-effects
- Neutralisation of individual
drug’s side-effects
- Increased patient compliance
- Lesser cost of therapy
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| Fixed-dose
combinations as recommended by JNC-VI (1997) guidelines |
- Calcium channel blocker and
Beta-blocker (e.g. Amlodipine and Atenolol)
- Calcium channel blocker and
ACE-inhibitor (e.g. Amlodipine and Lisinopril)
- ACE-inhibitor and Diuretic
(e.g. Lisinopril and Hydrochlorothiazide)
- Beta-blocker and Diuretic
(e.g. Atenolol and Hydrochlorothiazide)
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| Antihypertensive
therapy: Side-effects and Contraindications |
| Class
of drugs |
Main
side-effects |
Contraindications/Special
Precautions |
| Diuretics
(e.g. Hydrochlorothiazide |
Electrolyte
imbalance, Increased total and LDL cholesterol levels,
Decreased HDL cholesterol levels, Increased glucose levels,
Increased uric acid levels |
Hypersensitivity,
Anuria |
| Beta-blockers
(e.g. Atenolol) |
Impotence,
Bradycardia, Fatigue |
Hypersensitivity,
Bradycardia, Conduction disturbances, Diabetes, Asthma,
Severe cardiac failure |
| Calcium
channel blockers
(e.g. Amlodipine, Diltiazem)
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Pedel
edema, Headache |
In
case of non-dihydropy-ridine calcium channel blockers
(e.g. diltiazem) - Hypersensitivity, Bradycardia, Conduction
disturbances, Congestive heart failure, Left ventricular
dysfunction. In case of dihydropyridine calcium channel
blockers- Hypersensitivity |
| Alpha-blockers
(e.g. Doxazosin)
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Postural
hypotension |
Hypersensitivity |
| ACE-inhibitors
(e.g. Lisinopril)
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Cough,
Hypotension, Angioneurotic edema |
Hypersensitivity,
Pregnancy, Bilateral renal artery stenosis |
| Angiotensin-II
receptor blockers (e.g. Losartan) |
Headache,
Dizziness |
Hypersensitivity,
Pregnancy, Bilateral renal artery stenosis |
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| Further
reading |
- 1999 World Health Organization-International
Society of Hypertension Guidelines for the Management of
Hypertension. J. Hypertens 1999; 17: 151-183
- The Sixth Report of the Joint
National Committee on Prevention, Detection, Evaluation
and Treatment of High Blood Pressure. Arch Intern Med 1997;
157: 2413-2446
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