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Hypertension
Dr Zaka Haq, MBBS, MRCP
Cardiology Registrar
Queens Hospital Romford
Hypertension
Prevalence (UK)
NICE
Beta Blockers
Challenges
Primary Care
Hypertension-Overview
Hypertension itself-Introduction Types Classification Risk Factors Sequels Hypertension in special circumstances Management Follow Up Guidelines Referral to Secondary care
Hypertension, Introduction. Hypertension is one of the most important preventable
causes of premature morbidity and mortality in the UK. Hypertension is a major risk factor for stroke (ischemic and haemorrhagic), myocardial infarction, heart failure, chronic kidney disease, cognitive decline and premature death. Untreated hypertension may result in vascular and renal damage that can culminate in a treatment-resistant state.
The risk associated with increasing blood pressure is continuous, with each 2 mmHg rise in systolic blood pressure associated with a 7% increased risk of mortality from ischemic heart disease and a 10% increased risk of mortality from stroke.
Hypertension, Introduction.
Diastolic pressure is more commonly elevated in younger people. With ageing, systolic hypertension becomes a more significant problem.
The clinical management of hypertension is one of the most common 22 interventions in primary care, accounting for approximately £1 billion in drug costs alone in 2006.
Hypertension is often symptom less, so screening is vital - before damage is done. Many surveys continue to show that hypertension remains under diagnosed, undertreated and poorly controlled in the UK
Hypertension, Introduction
In many countries, 50% of the population older than 60 years has hypertension. Overall, approximately 20% of the world’s adults are estimated to have hypertension.
UK, 1 in every 4th person has Hypertension and this increases to 1 in every second person aged over 60.
Types of hypertension
Essential hypertension (Primary)
90%
No underlying cause
Secondary hypertension
5%
Underlying cause
Causes of Secondary Hypertension Renal disease Approximately 75% are from intrinsic renal disease:
glomerulonephritis, polyarteritis nodosa, systemic sclerosis, chronic pyelonephritis, or polycystic kidneys.
Approximately 25% are due to Reno vascular disease - most frequently atheromatous (e.g. elderly cigarette smokers with peripheral vascular disease) or fibromuscular dysplasia (more common in younger females).
Endocrine disease Cushing’s syndrome, Conn's syndrome, pheochromocytoma,
acromegaly, Hyperparathyroidism Others Coarctation, Preeclampsia, Drugs and toxins, e.g. alcohol, cocaine,
ciclosporin, tacrolimus, erythropoietin, adrenergic medications, decongestants containing ephedrine and herbal remedies containing liquorice
Definitions and Classifications of BP Levels
SBP DBP
Category* (mm Hg) (mm Hg)
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 > 110ISH > 140 < 90Reading to Remember 140 90
WHO-ISH Guidelines Subcommittee J Hypertens 1999; 17:151
Hypertension: Predisposing factors Age > 60 years Sex (men and postmenopausal women) Family history of cardiovascular disease Smoking High cholesterol diet Co-existing disorders such as diabetes, obesity and
hyperlipidaemia High intake of alcohol Sedentary life style Remember all these are predisposing factors for HTN but
they all including HTN are risk factors for Cardiovascular disease.
Diseases Attributable to Hypertension
HYPERTENSION
Gangrene of the Lower Extremities
Heart Failure
Left Ventricular Hypertrophy Myocardial
Infarction
Hypertensive Encephalopathy
Aortic Aneurysm
Blindness
Chronic Kidney Failure
Stroke Preeclampsia/Eclampsia
Cerebral Hemorrhage
Coronary Heart Disease
Adapted from Dustan HP et al. Arch Intern Med. 1996; 156: 1926-1935
Hypertension in special circumstances
HTN in Young-Causes HTN and Pregnancy-Cautions HTN and Diabetes - Proteinurea HTN and Renal Failure – vice versa Hypertensive Emergencies – urgency,
Emergency
Management of hypertension: the issues
Measurement Classification Investigations Risk assessment Non-pharmacological measures Treatment thresholds - 1st line - sequencing - beyond BP Treatment targets Concomitant therapy
Diagnosis and Measurement- 2011 If the first and second blood pressure measurements taken
during consultation are 140/90 mmHg or higher, offer 24-hour ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis of hypertension. [new 2011]
When using ABPM to confirm a diagnosis of hypertension, ensure that:
Blood pressure is measured for a total of 24 hours. At least two measurements per hour are taken during the
day (08:00 to 22:00). At least one measurement per hour is taken during the
night (22:00 to 08:00). Use the average daytime blood pressure measurement,
[new 2011]
Diagnosis and Measurement- 2011
When using home blood pressure monitoring (HBPM) to confirm a diagnosis of hypertension, ensure that:
For each blood pressure measurement, two consecutive measurements are taken, at least 1 minute apart and with the person seated.
Blood pressure measurements are taken twice daily, ideally in the morning and evening.
Blood pressure measurement continues for at least 4 days, ideally for 7 days.
Discard the measurements taken on the first day and use the average value of all the remaining measurements to confirm a diagnosis of HTN-2011
Potential indications for the use of ambulatory blood pressure monitoring
•Unusual variability
•Possible white coat hypertension
•Informing equivocal treatment decisions
•Evaluation of nocturnal hypertension
•Evaluation of drug-resistant hypertension
•Determining the efficacy of drug treatment over 24 hours
•Diagnoses and treatment of hypertension in pregnancy
•Evaluation of symptomatic hypotension
Why Home or ABPM?
2004 Guideline recommended that BP should not be diagnosed and treated based on one clinic BP measurement
Majority will need repeated clinic visits to confirm or refute the diagnosis
Inaccurate clinic measurements may weaken the relationship between BP and CVD risk
People who do not have sustained BP may be wrongly diagnosed and commenced on treatment with risk of side effects and unnecessary diagnosis and anxiety and cost.
Equipment
Training
Servicing
Investigations
Urine Biochemistry Blood Glucose Lipid Profile Electrocardiogram, CXR USG-KUB, Urinary catecholamine, TSH, CXR, ECHO,
urinary free cortisol, Specialist investigations
Life Style Modifications.
Maintain normal weight for adults (BMI 20-25 kg/m2) Reduce salt intake to <100 mmol /day (<6g NaCl or
<2.4g Na+/day) Limit alcohol consumption to <3 units/day for men and
<2 units/day for women Engage in regular aerobic physical exercise (brisk
walking rather than weightlifting) for >30 min per day Consume at least five portions/day of fresh fruit and
vegetables Reduce the intake of total and saturated fat STOP SMOKING
Next
Initiating and monitoring antihypertensive drug treatment, including blood pressure
targets
Drug therapy for hypertension
Class of drug Example Initiating dose Usualmaintenance dose
Diuretics Hydrochlorothiazide 12.5 mg o.d. 12.5-25 mg o.d.
-blockers Atenolol 25-50 mg o.d. 50-100 mg o.d.
Calcium Amlodipine 2.5-5 mg o.d. 5-10 mg o.d.channelblockers
-blockers Doxazosin 1 mg o.d. 1-8 mg o.d.
ACE- inhibitors Lisinopril 2.5-5 mg o.d. 5-20 mg o.d.
Angiotensin II Losartan 25-50 mg o.d. 50-100 mg o.d.receptor blockers -Centrally Acting Methyledopa Hydralazine
Antihypertensive therapy:Side-effects and Contraindications
Class of drugs Main side-effects Contraindications/Special Precautions
Diuretics Electrolyte imbalance, Hypersensitivity, Anuria(e.g. Hydrochloro- total and LDL cholesterol thiazide) levels, HDL cholesterol
levels, glucose levels, uric acid levels
-blockers Impotence, Bradycardia, Hypersensitivity, (e.g. Atenolol) Fatigue Bradycardia, Conduction
disturbances, Diabetes,Asthma, Severe cardiacfailure
Class of drug Main side-effects Contraindications/ Special
Precautions
Calcium channel blockers Pedal edema, Headache Non-dihydropyridine(e.g. Amlodipine, CCBs (e.g diltiazem)– Diltiazem) Hypersensitivity,
Bradycardia, Conductiondisturbances, Congestive heartfailure, Left ventriculardysfunction.Dihydropyridine CCBs–Hypersensitivity
-blockers Postural hypotension Hypersensitivity(e.g. Doxazosin)
ACE-inhibitors Cough, Hypertension, Hypersensitivity, Pregnancy,(e.g. Lisinopril) Angioneurotic edema Bilateral renal artery stenosis
Angiotensin -II receptor Headache, Dizziness Hypersensitivity, Pregnancy,blockers (e.g. Losartan) Bilateral renal artery stenosis
Antihypertensive therapy: Side-effects and Contraindications (Contd.)
Factors affecting choice of antihypertensive drug
The cardiovascular risk profile of the patient
Coexisting disorders
Target organ damage
Interactions with other drugs used for concomitant conditions
Tolerability of the drug
Cost of the drug
Choosing the right antihypertensive
Condition Preferred drugs Other drugs Drugs to be that can be used avoided
Asthma Calcium channel -blockers/Angiotensin -II -blockersblockers receptor blockers/Diuretics/
ACE-inhibitors
Diabetes -blockers/ACE Calcium channel blockers Diuretics/mellitus inhibitors/ -blockers
Angiotensin -IIreceptor blockers
High cholesterol -blockers ACE inhibitors/ Angiotensin -II -blockers/levels receptor blockers/ Calcium Diuretics
channel blockers
Elderly patients Calcium channel -blockers/ACE- (above 60 years)blockers/Diuretics inhibitors/Angiotensin -II
receptor blockers/- blockers
BPH -blockers -blockers/ ACE inhibitors/
Angiotensin -II receptor
blockers/ Diuretics/
Calcium channel blockers
Limitations on use of antihypertensives in patientswith coexisting disorders
Coexisting Diuretic -blocker ACE All CCB -blockerDisorder inhibitor antagonist
Diabetes Caution/x Caution/x
Dyslipidaemia x x
CHD
Heart failure /Caution Caution
Asthma/COPD x /Caution
Peripheral Caution Caution Caution vasculardisease
Renal artery x x stenosis
Compelling and possible indications, contraindications, and cautions for the major classes of antihypertensive drugs Class of drug
Compelling indications
Possible indications
Caution
Compelling contra-indications
Alpha-blockers
Benign prostatic hypertrophy
Postural hypotension, heart failure
Urinary incontinence
ACE-inhibitors
Heart failure, LV dysfunction, post MI or established CVD, Type I diabetic nephropathy, 2o stroke prevention
Chronic renal disease, Type II diabetic nephropathy, proteinuric renal disease
Renal impairment
PVD Pregnancy, renovascular disease
ARBs ACE inhibitor-intolerance, Type II diabetic nephropathy, hypertension with LVH, heart failure in ACE-intolerant patients, post MI
LV dysfunction post MI, intol-erance of other antihypertensive drugs, proteinuric renal disease, chronic renal disease,
heart failure
Renal impairment PVD
Pregnancy, renovascular disease
Compelling and possible indications, contraindications, and cautions for the major classes of antihypertensive drugs Class of drug
Compelling indications
Possible indications
Caution
Compelling contraindications
Beta-blockers MI, Angina
Heart failure Heart failure, PVD,
Diabetes (except with CHD)
Asthma/COPD, Heart block
CCBs (dihydropyridine)
Elderly, ISH Angina - -
CCBs (rate limiting)
Angina Elderly Combination with beta-blockade
Heart block Heart failure
Thiazide/thiazide-like diuretics
Elderly ISH Heart failure 2 o stroke prevention
Gout
WHICH PATIENTS NEED TREATMENT
Concentrate Bp Reading Target Organ Damage 10 Year CVD Risk Diabetes Young Hypertensives
Initiating Treatment
Offer people older than 80 years the same antihypertensive drug treatment as people aged 55–80 years, taking into account any comorbidities 2011
Offer Stage 1 Hypertensive's treatment if they have target organ damage or 86 established cardiovascular disease or renal disease or diabetes or a 10-year cardiovascular risk equivalent to 20% or
greater. [new 2011]
Initiating Treatment
Hypertension is not controlled with monotherapy in at least 50% of patients; in these patients combination therapy is required
Offer antihypertensive drug treatment to people with stage 2 hypertension. [new 2011]
For people younger than 40 years with stage 1 hypertension and no evidence of target organ damage, cardiovascular (CV) disease, renal disease or diabetes, consider seeking specialist evaluation of secondary causes of hypertension and a more detailed assessment of potential target organ damage. This is because 10-year CV risk assessments can underestimate the lifetime risk of CV events in these people -new 2011
Target organ damageor
cardiovascular complicationsor
diabetesor
10 year CVD risk† 20%
>180/110 160 179100 109
140 15990 99
130 13985 89
<130/85
160/100 140 15990 99
<140/90
No target organ damageand
no cardiovascular complicationsand
no diabetesand
10 year CVD risk† <20%
* ** ***
Treat Treat Treat Observe, reassessCVD risk yearly
Reassessyearly
Reassessin 5 years
* Unless malignant phase of hypertensive emergency confirm over 1 2 weeks then treat** If cardiovascular complications, target organ damage or diabetes is present, confirm over 3 4 weeks then treat; if absent re-measure
weekly and treat if blood pressure persists at these levels over 4 12*** If cardiovascular complications, target organ damage, or diabetes is present, confirm over 12 weeks then treat: if absent re-measure
monthly and treat if these levels are maintained and if estimated 10 year CVD risk is 20%† Assessed with CVD risk chart
THRESHOLDS FOR INTERVENTIONInitial blood pressure (mmHg)
Choosing drugs for patients newly diagnosed with hypertension: NICE/BHS
Antihypertensive Drug Treatment - 2011
Treatment Recommendations – General Concepts
Offer people with isolated systolic hypertension (systolic BP 160 mmHg or more) the same treatment as people with both raised systolic and diastolic blood pressure. [2004]
Offer people older than 80 years the same antihypertensive treatment as people aged 55–80 years, taking into account any co morbidities. [new 2011]
Offer step 1 antihypertensive treatment with an ACE inhibitor or a low-cost ARB to people aged under 55 years. If an ACE inhibitor is used and not tolerated, offer an ARB. [new 2011]
Do not combine an ACE inhibitor with an ARB to treat hypertension. [new 2011]
Step 1 Treatment Recommendations
Offer step 1 antihypertensive treatment with a CCB to people aged 55 years and older and to black people of African and Caribbean descent of any age. If a CCB is not suitable, for example because of oedema or intolerance, or if there is evidence of heart failure, or a high risk of heart failure, offer a thiazide -like diuretic . [new 2011]
If a diuretic is required, choose a thiazide -like diuretic, such as chlortalidone (12.5 mg–25.0mg once daily) or indapamide (2.5 mg once daily) in preference to a conventional thiazide diuretic such as bendroflumethiazide or hydrochlorothiazide. [new 2011]
Step 2 Treatment Recommendations
If step 2 antihypertensive treatment is required, offer a CCB in combination with either an ACE Inhibitor or a low-cost ARB. If a CCB is not suitable, for example because of oedema or intolerance, or if there is evidence of heart failure or a high risk of heart failure, offer a thiazide-like diuretic [new 2011]
Step 3 Treatment Recommendations
If treatment with three drugs is required, the combination of ACE inhibitor or angiotensin II receptor blocker, calcium-channel blocker and thiazide-like diuretic should be used. [2006]
Step 4 Treatment Recommendations Resistant Hypertension
For treatment of resistant hypertension at step 4, consider further diuretic therapy with low-dose spironolactone (25 mg once daily) if blood potassium levels are lower than 4.5 mmol/l and eGFR is higher than 60 ml/min/1.73m2. If blood potassium levels are higher than 4.5 mmol/l, consider therapy with a higher-dose thiazide-like diuretic treatment. [new 2011]
When using further diuretic therapy for resistant hypertension at step 4, monitor blood sodium and potassium and renal function within 1 month and repeat as required thereafter. [new 2011]
Step 4 Treatment Recommendations Resistant Hypertension
If further diuretic therapy for resistant hypertension at step 4 is not tolerated, contraindicated or ineffective, consider an alpha- or beta-blocker. [new 2011]
If blood pressure remains uncontrolled with the optimal or maximum tolerated doses of four drugs, seek expert advice if it has not yet been obtained. new 2011]
BP Targets in Various Guidelines
Guidelines Uncomp.HTN DM C RF
USA (JNC VII [2003]) <140/90 mmHg <130/80 mmHg <130/80 mmHg Europe (ESH 2007) <140/90 mmHg <130/80 mmHg <130/80 mmHg China (CSH 2005) <140/90 mmHg <130/80 mmHg <130/80 mmHg Russia <140/90 mmHg <130/80 mmHg <130/80 mmHg Korea (KSH 2004) <140/90 mmHg <130/80 mmHg <130/80 mmHg
WHOISH SBP <140 mmHg <130/80 mmHg <130/80 mmHg BHS IV 2004 <140/85 mmHg <130/80 mmHg <130/80 mmHg
Hypertension in DRAFT NICE
Big changes with impact on Primary Care
Hypertension as a disease
Primary not Essential hypertension
At least ¼ of adult UK population have a BP > = 140/90 or hypertension
More than ½ of those 60 or more
Hypertension in NICE ( DRAFT)
Strong emphasis on diagnosis and measuring blood pressure Ensuring training for those taking blood pressure
measurements Validation, maintenance and calibration of devices and
correct cuff size Standard procedure for measurement resting 5-10 min Check pulse rhythm for AF Check for postural drop If first and second readings are both higher than 140/90 to
arrange an ABPM If blood pressure > 180/110 start treatment
Suggested indications for specialistreferral
Urgent treatment needed • Accelerated hypertension (severe hypertension and grade III-IV retinopathy) • Particularly severe hypertension ( > 220/120 mm Hg) • Impending complications (for example, transient ischemic attack, left ventricular failure)
Possible underlying cause • Any clue in history or examination of a secondary cause, such as hypokalaemia with increased or high normal plasma sodium (Conn’s syndrome) • Elevated serum creatinine • Suspected phaeochromocytome with labile BP or postural hypotension,
headache, palpitations, pallor
Suggested indications for specialistreferral
• Proteinuria or haematuria • Sudden onset or worsening of hypertension • Resistant to multidrug regimen ( ≥ 3 drugs) • Young age (any hypertension < 20 years; needing treatment < 30 years)
Therapeutic problems • Multiple drug intolerance • Multiple drug contraindications • Persistent non-adherence or non-compliance
Special situations • Unusual blood pressure variability • Possible white coat hypertension • Hypertension in pregnancy
Groups that will not be covered 420
People with diabetes. Children and young people (younger than 18 years). Pregnant women. Secondary causes of hypertension (for example, Conn's
adenoma, phaeochromocytoma and renovascular hypertension).
People with accelerated hypertension (that is, severe acute hypertension 426 associated grade III retinopathy and encephalopathy).
People with acute hypertension or high blood pressure in emergency care
Drugs in special conditions
Condition
Pregnancy
Coronary heart disease
Congestive heart failure
Preferred Drugs
Nifedipine, labetalol, hydralazine, beta-blockers, methyldopa, prazosin
Beta-blockers, ACE inhibitors, Calcium channel blockers
ACE inhibitors,beta-blockers
1999 WHO-ISH guidelines
HTN and Pregnancy
•Chronic hypertension (2-4%)
•Hypertension first identified in early pregnancy
•Hypertension that persists postpartum
•Gestational hypertension (2-4%) Non- proteinuric hypertension
•Pre- eclampsia 3% primigravida at term and 0.5% pre-term
HTN and Pregnancy
•During pregnancy, BP target; 130/80 - 150/100mmHg •If BP ≥150/100; start labetolol/methyldopa/nifedipine SR •Avoid ACE-I and ARBs during pregnancy •Consider secondary hypertension in women with severe
hypertension especially in early pregnancy and postpartum •Consider prophylactic low-dose aspirin from 12 weeks •Both systolic and diastolic hypertension important •Early onset pre-eclampsia, a serious threat to mother and
foetus •Long-term follow up is essential for future woman’s
health
CKD and Diabetes
In people with CKD aim for:
•systolic blood pressure below 140 mmHg(target range 120–139 mmHg)
•diastolic blood pressure below 90 mmHg
In people with CKD and diabetes - or when ACR 70mg/mmol, aim for:
•systolic blood pressure below 130 mmHg(target range 120–129 mmHg)
•diastolic blood pressure below 80 mmHg
Place Of Beta blockers
Beta-blockers are not a preferred initial therapy for hypertension. However, beta-blockers may be considered in younger people, particularly:
those with an intolerance or contraindication to ACE inhibitors and angiotensin -II receptor antagonists or
women of child-bearing potential or people with evidence of increased sympathetic drive. In these circumstances, if therapy is initiated with a
beta-blocker and a second drug is required, add a calcium-channel blocker rather than a thiazide -type diuretic to reduce the person’s risk of developing diabetes.
Other medications for hypertensive patients
Primary prevention
(1) Aspirin: use 75mg daily if patient is aged 50 years with blood pressure controlled to <150/90 mm Hg and either; target organ damage, diabetes mellitus, or 10 year risk of cardiovascular disease of 20% (measured by using the new Joint British Societies’ cardiovascular disease risk chart)
(2) Statin: use sufficient doses to reach targets if patient is aged up to at least 80 years, with a 10 year risk of cardiovascular disease of 20% (measured by using the new Joint British Societies’ cardiovascular disease risk chart) and with total cholesterol concentration 3.5mmol/l
(3) Vitamins—no benefit shown, do not prescribe
Secondary prevention (including patients with type 2 diabetes)
(1) Aspirin: use for all patients unless contraindicated
(2) Statin: use sufficient doses to reach targets if patient is aged up to at least 80 years with a total cholesterol concentration 3.5 mmol/l
(3) Vitamins— no benefit shown, do not prescribe
Other medications for hypertensive patients