hypertension

Dr. G.S. Jogdand, M.D. Ph.D.Professor & Head,

Community Medicine Department

Kieran McGlade Nov 2001 Department of General Practice QUB

DefinitionSir George peckering has made an

observation that hypertension is distributed in the population as a continuous variable showing normal distribution.

Therefore clear cut definition cannot be given, however for operational feasibility cut off points are taken.

Normotension: systolic B.P. <130 mm. of Hg.Diastolic B.P. < 85 mm. of Hg.


In 2000 global prevalence of HTN was 26.4% and is expected to be >30% by 2025.

It is highest in Poland (70%) and lowest in rural India (3.4%).

Only few populations living at high altitude are belonging to primitive cultures have exceptionally low B.P.


Global Magnitude of the Problem

Indian ScenarioIn India prevalence ranging from 3 to 40%Chennai-21% of adult populationJaipur-30% of adult populationMumbai-34% of adult populationThiruvananthapuram-41% of adult population


Classification of hypertensionCategory Systolic B.P. Diastolic B.P.

Normal <130 mm. Hg. < 85 mm. Hg.

High normal 130-139 mm. Hg. 85-90 mm. Hg.

Hypertension

Stage 1. Mild 140- 159 mm. Hg. 90- 99 mm. Hg.

Stage 2. Moderate 160- 179 mm. Hg. 100-109 mm. Hg.

Stage 3. Severe > 180 mm. Hg. > 110 mm. Hg.


Rule of halves in Hypertension


Aetiology of HypertensionPrimary – 90-95% of cases – also termed

“essential” or “idiopathic”Secondary – about 5% of cases

Renal or reno-vascular diseaseEndocrine disease

Phaeochromocytoma Cushing’s syndrome Conn’s syndrome Acromegaly and hypothyroidism

Coarctation of the aortaIatrogenic

Hormonal / oral contraceptive NSAIDs


Patho-physiology of hypertensionAtherosclerotic changes in the body:Thickening of blood vessels » increase in

peripheral resistance » leads to hypertension. Hormonal changes in the body.Some secondary infections.No obvious cause.


Risk factors for HypertensionNon modifiable:Age.Sex.Ethnicity.Genetic factors.


Risk factors continued….Modifiable:Obesity.Intake of table salt.Intake of saturated fats.Consumption of alcohol.Smoking.Sedentary life style.Environmental stress.S.E. status.


Complications of HypertensionCardiomegaly: Uncontrolled hypertension leads to

thickening of heart musculature.Damage to the target organs:Hypertensive occulopathy.Hypertensive nephropathy. Hypertensive encephalopathy.Myocardial infarction.Stroke.



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 fibres have undergone hypertrophy.

Treatment (H O T)Hypertension Optimal TreatmentLargest intervention trial in hypertension.

Published in 1998Conducted in General Practice. 18,790

patients in 26 countriesFollowed up for an average of 3.8 years


H O T FindingsLowest incidence of major CV events

occurred at a mean achieved DBP of 83 mm of hg. This target (compared to mean achieved of 105 mmHg was associated with a 30% reduction in main CV events).

In diabetes – Diastolic B.P. ≤ 80 mm. Hg. 51 % lower risk compared to 90 mm. Hg.



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 DiabetesHypertension 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.


StagesIdentification of hypertensive patientsBaseline investigationsInitiating therapyReviewing patientsStepping up therapyMotivation and compliance


Investigation of the New HypertensiveHistory and examinationExclude secondary HypertensionUrea and electrolytesComplete blood picture and ESRECGLipid profileChest x-ray no longer routinely indicated


Clinical clues to renal vascular diseaseHypertension under 50 Yrs. of age.Generalized vascular (esp. peripheral)

disease.Mild – moderate renal dysfunction.Sudden onset pulmonary oedema.


Ladder ApproachBendrofluazideBendrofluazide + Atenolol or ACECalcium Channel blockerAlpha blocker


Tailored ApproachAssessment of overall cardiovascular riskRecognition of co-morbiditiesLipid profileRenal functionExisting contraindications



Compelling and possible indications and contraindications 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 *

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


Diuretic-

blockerCCB

ACE inhibitor

-blocker

Diuretic - -

-blocker - * -

CCB - * -

ACE inhibitor - -

-blocker -

* Verapramil + beta-blocker = absolute contra-indication

ACE Inhibitor Side EffectsCough (15% of patients. Is reversible)Taste disturbance (reversible)AngiodemaFirst-dose hypotensionHyperkalaemia ( esp. in patients with type II

diabetes and renal dysfunction)


Follow-upFor 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)


Drug Treatment of Essential Hypertension in Older PeopleHypertension 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 PeopleThere 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. •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 Points15 – 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.


Prevention & ControlPrimordial prevention.Primary prevention.Secondary prevention.Primordial prevention strategy: Targeted at

controlling the emergence and spread of risk factors in the community.

Primary prevention strategies: 1. Population strategy involves multi-dimensional

approachNutrition education: reduction of salt intake, not

more than 5gms./dayKieran McGlade Nov 2001 Department of General Practice QUB

Continued….Weight reduction: Life style modification.Cessation of smoking and alcohol intake.Non phamacotheraputic intervention:

Practicing yoga and meditation regularly.Health education.Self care. High risk strategy: Appropriate if the prevalence of risk factors

in the community is low.


Early detection of cases.Early initiation of treatment.Follow up of cases.


Secondary prevention

Web based referencesBritish Hypertension Society:

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

http://www.hyp.ac.uk/bhs/gl2000.htmHypertension audit protocol from Leicester

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


Thank You


hypertension

Health & Medicine

years kieran mcgladenov

problem kieran mcgladenov

compliance kieran mcgladenov

uncontrolled hypertension

severe hypertension

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hypertensive heart disease