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MEDICAL TELECONFERENCE: Hypertension. 1 st year Post-Graduate Family Medicine Dr Munirah Mohd Basar. GENERAL OBJECTIVE. The aim of the session is to enable the family practitioner to have sufficient knowledge and skills to diagnose and manage hypertensive patients . INTRODUCTION.
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MEDICAL TELECONFERENCE:Hypertension 1st year Post-Graduate Family Medicine Dr Munirah Mohd Basar
GENERAL OBJECTIVE • The aim of the session is to enable the family practitioner to have sufficient knowledge and skills to diagnose and manage hypertensive patients.
INTRODUCTION • Major risk factor for Cardiovascular, cerebrovascularand renal disease • Prevalance of HPT was 43% in 2006 (age ≥ 30 years old) : 30% increase in 10 years • 64% remain undiagnosed (silent disease) • Only 26% achieved blood pressure control
DEFINITION • HYPERTENSION • persistent elevation of SBP ≥ 140mmHg and/or DBP ≥ 90mmHg • Prehypertension • SBP 120-139mmHg and/or DBP 80 to 89mmHg
A 30 year old Indian man come to your clinic for a medical examination for insurance. He is found to have high blood pressure of 160/120mmHg (one reading). He is otherwise well, with no other alarming symptoms.
Diagnosing hypertension • If blood pressure measured in the clinic is 140/90 mm Hg or higher: • Take a second measurement during the consultation • If the second measurement is substantially different from the first, take a third measurement • Record the lower of the last two measurements as the clinic blood pressure.
If the clinic blood pressure is 140/90 mm Hg or higher, use ambulatory blood pressure monitoring to confirm the diagnosis of hypertension. • This strategy will improve the accuracy of the diagnosis compared with current practice and was also shown to be cost effective—indeed, cost saving—for the NHS. (Updated recommendation) [Based on a systematic review of randomised controlled trials ranging in quality from poor to good and on cost effectiveness evidence]
When using ambulatory blood pressure monitoring to confirm a diagnosis of hypertension, • ensure that at least two measurements an hour are taken during the person’s usual waking hours (for example, between 0800 and 2200). • Use the average value of at least 14 measurements taken during the person’s usual waking hours to confirm a diagnosis of hypertension. (New recommendation) [Based on prognostic and reliability or reproducibility studies determined to be at low risk of bias]
If a person cannot tolerate ambulatory blood pressure monitoring, home blood pressure monitoring is a suitable alternative to confirm the diagnosis. (New recommendation) [Based on a systematic review of randomisedcontrolled trials ranging in quality from poor to good and on cost effectiveness evidence]
When using home blood pressure monitoring to confirm a diagnosis of hypertension: • For each blood pressure recording, take two consecutive measurements, at least one minute apart and with the person seated, and • Record blood pressure twice daily, ideally in the morning and evening, and • Continue recording blood pressure for at least four days, ideally for seven days, and • Discard the measurements taken on the first day and use the average value of all the remaining measurements to confirm a diagnosis of hypertension. • (New recommendation) [Based on prognostic and reproducibility studies determined to be at low risk of bias]
While waiting for a confirmed diagnosis of hypertension, investigate target organ damage (such as left ventricular hypertrophy, chronic kidney disease, and hypertensive retinopathy) and formally assess cardiovascular risk. (New recommendation) [Based on the experience and opinion of the GDG] • Use risk equations to assess cardiovascular risk—for example, the Framingham risk calculator7 (as used in the Joint British Societies’ risk charts available in the British National Formulary and QRISK2 [Based on the NICE guideline on lipid modification9 ]
DIAGNOSIS AND ASSESSMENT • Evaluation • To exclude secondary cause of hypertension • To ascertain the presence or absence of target organ damage • To assess lifestyle and identify other cardiovascular risk factors or concomitant disorders that affect risk factors, prognosis and guide treatment • History, physical examination and investigation
HISTORY • duration and level of elevated BP if known • symptoms of secondary causes of hypertension • symptoms of target organ damage, e.g. coronary heart disease (CHD) and cerebrovasculardisease • symptoms of concomitant disease that will affect prognosis or treatment, e.g. diabetes mellitus, renal disease and gout • family history of hypertension, CHD, stroke, diabetes, renal disease or dyslipidaemia • dietary history including salt, fat, caffeine and alcohol intake • drug history of either prescribed or over-the-counter medication (NSAIDS, nasal decongestants) and herbal treatment • lifestyle and environmental factors that will affect treatment and outcome, e.g. smoking, physical activity, work stress and • excessive weight gain since childhood
Physical examination • General examination including height, weight and waist circumference • Two or more BP measurements separated by two minutes with the patient either supine or seated; and after standing for at least one minute • Measure BP on both arms • Fundoscopy • Cardiovascular examination : examination for carotid bruit, abdominal bruit, presence of peripheral pulses and radio-femoral delay, evidence of cardiac failure • Abdominal examination for renal masses, aortic aneurysm and abdominal obesity • Neurological examination to look for evidence of stroke • Signs of endocrine disorders, e.g. Cushing syndrome, acromegaly and thyroid disease
Investigations • Full blood count • Urinalysis • Measurement of urine albumin excretion or albumin/creatinineratio • Renal function tests (urea, creatinine, serum electrolytes and uric acid) • Fasting blood sugar • Lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides) • Electrocardiogram (ECG) • Chest X-ray
PREHYPERTENSION • 37% of Malaysian population has prehypertension (NHMS 1996) • For inviduals aged 40-70 y.o, risks of CVD rises progressively beginning 117/75mmHg • It is been estimated that almost a third of BP-related deaths from CHD occurs in individuals with SBO between 110-139mmHg
All patients should be managed with non-pharmacologic interventions/therapeutic lifestyle modifications to lower BP • Yearly follow-up -> to detect and treat hypertension as early as possible • Pharmacological treatment? • Individual patient’s global CVD risk • Eg: DM/CKD – treat if BP > 130/80
Thresholds for intervention • If the person has severe hypertension (clinic blood pressure ≥180/110 mm Hg), consider starting antihypertensive drug treatment immediately, without waiting for the results of ambulatory or home blood pressure monitoring. (New recommendation) [Based on the experience and opinion of the GDG]
Offer antihypertensive drug treatment to people aged under 80 years with stage 1 hypertension (that is, an average ambulatory or home blood pressure of ≥135/85 mm Hg and <150/95 mm Hg; a clinic blood pressure of ≥140/90 mm Hg and <160/100 mm Hg) and who have one or more of the following: • Target organ damage • Established cardiovascular disease • Renal disease • Diabetes • A 10 year cardiovascular risk equivalent to ≥20%. *(Updated recommendation) [Based on systematic reviews and meta-analyses of low quality observational and low to high quality randomised controlled trials; prognostic studies determined to be at low risk of bias; and a blood pressure equivalence study of low quality]
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension (an average ambulatory or home blood pressure of ≥150/95 mm Hg; a clinic blood pressure ≥160/100 mm Hg) irrespective of the presence of target organ damage, cardiovascular disease, renal disease, or the 10 year risk of cardiovascular disease. *(Updated recommendation) [Based on systematic reviews and meta-analyses of low quality observational and low to high quality randomised controlled trials; prognostic studies determined to be at low risk of bias; and a low quality observational study]
For people aged under 40 years with stage 1 hypertension and no evidence of target organ damage, cardiovascular disease, renal disease or diabetes, consider seeking specialist evaluation for secondary causes of hypertension and a more detailed assessment of potential target organ damage. This is because 10 year cardiovascular risk assessments can underestimate the lifetime risk of cardiovascular events in these younger people. *(Updated recommendation) [Based on systematic reviews and meta-analyses of low quality observational and low to high quality randomised controlled trials; prognostic studies determined to be at low risk of bias; and a blood pressure equivalence study of low quality]
Management • Non-pharmacological (Therapeutic lifestyle modification) • Pharmacological
NON-PHARMACOLOGICAL MANAGEMENT • Weight reduction • Most beneficial in patients > 10% overweight • Aim for BMI 18.5 to 23.5kg/m2 • Target 5% reduction of body weight • 4.5 kg weight reduction significantly reduces BP
2) Sodium intake • Elderly more sensitive to sodium intake • Intake of <100mmol of sodium or 6g of NaCl a day is recommended (= <1¼ teaspoonfuls of salt or 3 teaspoonfuls of monosodium glutamate 3) Avoidance of alcohol intake • No more than 21 units (men) and 14 units (women) *1 unit = ½ pint of beer OR 100mls of wine OR 20mls of proof whisky
4) Regular physical exercise • Aerobic exercise more effective than resistance training • Cardiovascular health : “milder” exercise such as brisk walking for 30 – 60 minutes at least 3x/week 5) Healthy eating - Rich in fruits, vegetables and dairy products with reduced saturated and total fat lower BP (11/6mmHg in HPT patients and 42mmHg in preHPT patients)
6) Cessation of smoking • Important in overall management of CVD risk 7) Others • Stress management • Micronutrient alterations • Dietary supplementations with fish oil, potassium, calcium, magnesium, and fibre(limited or unproven efficacy)
PHARMACOLOGICAL MANAGEMENT • Stage I HPT – 3-6 months observational period (unless target organ involvement is already evident) • First line monotherapy – ACEIs, ARBs, CCBs, and diuretics • Beta blocker are no longer recommended for 1st line monotherapy in this group of patients • B-blocker may be considered in younger people: • Those with an intolerance or contraindication to ACEIs or ARBs • Women of child bearing potential or • Patients with evidence of increase sympathetic drive
Target BP : • <140/80mmHg for patients <65 years old • <130/80mmHg for diabetic/CKD patients • Resistant Hypertension • BP >140/90mmHg with 3 drugs including diuretics at near maximal doses • Look for possible causes • Noncompliance • Secondary hypertension • White coat hypertension • Excessive sodium intake, excessive liquorice intake and drug interactions • Complications of long standing HPT such as nephrosclerosis, loss of aortic distensibility and atherosclerotic renal artery stenosis
Aim for a target clinic blood pressure below 140/90 mm Hg in people aged under 80 years with treated hypertension. *(Updated recommendation) [Based on systematic reviews of very low to moderate quality randomisedcontrolled trials, and observational studies] • Aim for a target clinic blood pressure below 150/90 mmHg in people aged 80 years and over with treated hypertension. *(Updated recommendation) [Based on a systematic review and meta-analysis that included moderate and high quality randomised controlled trials]
SEVERE HYPERTENSION • Definition : BP > 180/110mmHg • Presentation: • Asymptomatic i.e Incidental findings • Non-specific symptoms : headache, dizziness, lethargy • Symptoms & signs of acute target organ damage including acute coronary syndromes, acute renal failure, dissecting aneurysm, hypertensive encephalopathy
Asymptomatic severe hypertension • Hypertensive urgencies • Hypertensive emergencies
Hypertensive urgencies • Grade III or IV retinal changes (also known as accelerated and malignant hypertension respectively) but no overt organ failure • BP measurement repeated after 30minutes bed rest • Aim for 25% reduction of BP over 24hrs but not lower than 160/90mmHg