kieran mcglade nov 2001 department of general practice qub hypertension

Kieran McGlade Nov 2001

Department of General Practice QUB

Hypertension



Aetiology of Hypertension• Primary – 90-95% of cases – also termed “essential” of “idiopathic”• Secondary – about 5% of cases

– Renal or renovascular disease– Endocrine disease

• Phaeochomocytoma• Cusings syndrome• Conn’s syndrome• Acromegaly and hypothyroidism

– Coarctation of the aorta– Iatrogenic

• Hormonal / oral contraceptive• NSAIDs



This left ventricle is very thickened (slightly over 2 cm in thickness), but the rest of the heart is not greatly enlarged. This is typical for hypertensive heart disease. The hypertension creates a greater pressure load on the heart to induce the hypertrophy.



The left ventricle is markedly thickened in this patient with severe hypertension that was untreated for many years. The myocardial fibers have undergone hypertrophy.



H O T

• Hypertension Optimal Treatment

• Largest intervention trial in hypertension. Published in 1998

• Conducted in General Practice. 18,790 patients in 26 countries

• Followed up for an average of 3.8 years



H O T Findings

• Lowest incidence of major CV events occurred at a mean achieved DBP of 83 mmhg. This target (compared to mean achieved of 105 mmHg was associated with a 30% reduction in main CV events.

• In diabetes – Diastolic< or = 80mmhg 51 % lower risk compared to 90 mmHg



Global heart threat from diabetes:

A global explosion in the number of cases of diabetes is threatening to reverse the reduction in deaths from heart disease in many western countries, including the United Kingdom. To coincide with World Diabetes Day on 14 November, Diabetes UK is calling for action to be taken to reduce the 20,000 deaths per year from coronary heart disease (CHD) among people with diabetes in the UK.



Hypertension and Diabetes

• Hypertension co-exists with type II in about 40% at age 45 rising to 60% at age 75.

• 70% of type II patients die from cardio-vascular disease.

• At least 60% of patients will require 2 or 3 antihypertensive agents to achieve tight control.



Stages

• Identification of hypertensive patients

• Baseline investigations

• Initiating therapy

• Reviewing patients

• Stepping up therapy

• Motivation and compliance



Investigation of the New Hypertensive

• History and examination• Exclude secondary Hypertension• Urea and electrolytes• FBP and ESR• ECG• Lipid profile

• Chest x-ray no longer routinely indicated



Clinical clues to renal vascular disease

• Hypertension under 50 Yrs of age.

• Generalised vascular (esp peripheral) disease.

• Mild – moderate renal dysfunction.

• Sudden onset pulmonary oedema.



Ladder Approach

• Bendrofluazide

• Bendrofluazide + Atenolol or ACE

• Calcium Channel blocker

• Alpha blocker



Tailored Approach

• Assessment of overall cardiovascular risk

• Recognition of co-morbidities

• Lipid profile

• Renal function

• Existing contraindications



Coronary Risk Calculator

• Launch risk calculator program



Compelling and possible indications and contrindications for the major classes of antihypertensive drugs INDICATIONS CONTRAINDICATIONS

CLASSS OF DRUG COMPELLING POSSIBLE POSSIBLE COMPELLING

-blockers Prostatism Dyslipidaemia Postural Hypotension Unrinary incontinence

Angiotensin converting enzyme (ACE) inhibitors Heart failure Left ventricular dysfunction

Chronic renal disease * Type II diabetic nephropathy

Renal impairment * Peripheral vascular disease †

Pregnancy Renovascular disease

Angiotensin II receptor antagonists Cough induced by ACE inhibitor ‡ Heart failure Intolerance of other antihypertensive drugs

Peripheral vascular disease Pregnancy Renovascular disease

blockers

Myocardial infarction Angina

Heart failure

Heart failure Dyslipidaemia Peripheral vascular disease

Asthma or COPD Heart block

Calcium antagonists (dihydropyridine) Isolated systolic hypertension (ISH) in elderly patients Angina Elderly patients

_ _

Calcium antagonists (rate limiting) Angina Myocardial infarction Combination with blockade Heart block Heart failure

Thiazides Elderly patients including ISH _ Dyslipidaemia Gout

* ACE inhibitors may be beneficial in chronic renal failure but should be used with caution. Close supervision and specialist advice are needed when there is established and

significant renal impairment † Caution with ACE inhibitors and angiotensin II receptor antagonists in peripheral vascular disease because of association with renovascular disease. ‡ If ACE inhibitor indicated -blockers may worsen heart failure, but in specialist hands may be used to treat heart failure British Hypertension Society Guidelines 2000



Therapeutic targets

Therapeutic targets *

Measured in clinic Mean daytime ABPM

or home measurement

Blood Pressure No diabetes Diabetes No diabetes Diabetes Optimal <140/85 <140/80 <130/80 <130/75 Audit Standard <150/90 <140/85 <140/85 <140/80

The audit standard reflects the minimum recommended levels of BP control. Despite best practice, it may not be

achievable in some treated hypertensive patients. NB: Both systolic and diastolic targets should be reached

British Hypertension Society Guidelines



Logical Combinations

Diuretic-

blockerCCB

ACE inhibitor

-blocker

Diuretic - -

-blocker - * -

CCB - * -

ACE inhibitor - -

-blocker -

* Verapamil + beta-blocker = absolute contra-indication



ACE Inhibitor Side Effects

• Cough (15% of patients. Is reversible)

• Taste disturbance (reversible)

• Angiodema

• First-dose hypotension

• Hyperkalaemia ( esp. in patients with type II diabetes and renal dysfunction)



Follow-up

• For patients with BP stabilised by management, follow up should normally be three monthly (interval should not exceed 6 months), at which the following should be assessed by a trained nurse:

• * Measurement of BP and weight * Reinforcement of non-pharmacological advice * General health and drug side-effects * Test urine for proteinuria (annually)



Web based references

• British Hypertension Society: http://www.hyp.ac.uk/bhs/

• Summary Guidelines 2000:http://www.hyp.ac.uk/bhs/gl2000.htm

• Hypertension audit protocol from Leicesterhttp://www.le.ac.uk/genpractice/gpaudit/htnprot.html

http://www.hyp.ac.uk/bhs/

http://www.hyp.ac.uk/bhs/gl2000.htm

http://www.hyp.ac.uk/bhs/gl2000.htm

http://www.le.ac.uk/genpractice/gpaudit/htnprot.html

http://www.le.ac.uk/genpractice/gpaudit/htnprot.html



Drug Treatment of Essential Hypertension in Older People

• Hypertension is very common, occuring in over 50% of older people, and is a major risk factor for stroke and ischaemic heart disease.

• Drug treatment of hypertension in older people saves lives and prevents unnecessary morbidity.

• Treating isolated systolic hypertension also saves lives.



Drug Treatment of Essential Hypertension in Older People

• There is strong evidence to support the use of diuretics as first-line agents.

• Antihypertensive treatments are most cost-effective when targeted at older patients.

• There is evidence of under detection and under treatment of hypertension.

• Factors influencing patient adherence with treatment are not well understood and require further research.



RECOMMENDATIONS (for the treatment of the elderly)

•Through the wider use of antihypertensive therapies more older people would be able to maintain a healthy and active lifestyle. •Through the wider use of antihypertensive therapies more older people would be able to maintain a healthy and active lifestyle. •For first-line agents there is strong evidence to support the use of diuretics and some evidence for the use of beta-blockers. •Systems to ensure that older people with hypertension are diagnosed, treated and followed up need to be developed. •A system of audit should be cultivated to assure adequate treatment. •High quality research on patient adherence with antihypertensive medications is needed.

NHS Centre for reviews and dissemination 1999



Practical Points

• 15 – 20% of adult western population.

• Isolated systolic hypertension just as dangerous.

• Primary cause identified in only 5%.

• Investigate – Urine, FBP, ESR, ECG, U&E, Lipids.

• Target < 140/85.

• Bendrofluazide 2.5 mg a good starting point.

• Refer patients needing more than 3 drugs to control their hypertension.

kieran mcglade nov 2001 department of general practice qub hypertension

Documents

kieran mcglade

hypertensive heart disease

mmhg slide

compliance slide

coronary heart disease

cardio vascular disease

diabetes hypertension

severe hypertension