MPharmProgramme Hypertension (HTN) Slide 1 of 30
Overview Definition Prevalence Type Causes Diagnosis Management Patients perspective Slide 2 of 30
Definition It is not a disease! So what is it? What two factors are used to determine blood pressure? How can these two factors be affected to cause HTN? What is a normal, high or low BP? Slide 3 of 30
What is it a risk factor for? MI, HF, Stroke, CKD, PVD If HTN is identified then a full assessment of cardiovascular risk should be undertaken not just managing the BP. Remember, if a patient has HTN they do NOT have established CVD, so they would be treated as primary prevention rather than secondary prevention. Slide 4 of 30
Risk Effective management of HTN 35-40% reduction in stroke incidence 20-25% reduction in myocardial infarction >50% reduction in heart failure SBP rise of 20 mmhg led to a doubling of agespecific mortality rates for stroke, IHD, and other vascular disease Lewington et al, 2002 5 mmhg reduction can reduce risk of renal failure by 25% HTN leads to increased morbidity and mortality Slide 5 of 30
Jackson et al Lancet 2005 HTN & CV RISK Slide 6 of 30
Hypertension and cardiovascular risk Jackson et al Lancet 2005 Absolute cardiovascular disease risk (iethe probability that a patient will have a cardiovascular event in a defined period) is determined by the synergistic effect of cardiovascular risk factors present. The most powerful risk predictors are age, previous symptomatic cardiovascular disease and pathophysiological changes, such as left ventricular hypertrophy and renal impairment but many factors including increasing blood pressure and lipids, smoking, and male sex interact to determine absolute risk. Single risk factors such as blood pressure or cholesterol have a minor effect on a patients absolute risk in the absence of other risk factors, but they can have a major effect in the presence of several risk factors Slide 7 of 31 MPHM13 Cardiovascular - Hypertension
Slide 8 of 31 MPHM13 Cardiovascular - Hypertension
Prevalence 30% of people aged 45-54 have a BP of at least 140/90 70% of people aged >75 have a BP of at least 140/90 Race Greater prevalence in African-Caribbean popn compared to Caucasian popn Slide 9 of 30
Type Primary (essential) HTN Incidence? Causes? Secondary HTN Incidence? Causes? Is HTN life threatening? Malignant or accelerated HTN Slide 10 of 30
Pathophysiology 2 o HTN Slide 11 of 30
Hypertension Stage 1 hypertension: Clinic blood pressure (BP) is 140/90 mmhg or higher and ABPM or HBPM average is 135/85 mmhg or higher. Stage 2 hypertension: Clinic BP 160/100 mmhg or higher and ABPM or HBPM daytime average is 150/95 mmhg or higher. Severe hypertension: Clinic BP is 180 mmhg or higher or Clinic diastolic BP is 110 mmhg or higher Slide of 30
Diagnosis How do patients present? Taking a BP Manual or Machine? How and When? Slide 13 of 30
Diagnosing hypertension If the first blood pressure measurement is 140/90mmHg or greater, measure BP again after 1minute If the second measurement is substantially different from the first, take a third measurement after 1 minute Use the lower of the last two measurements as the recorded clinic blood pressure Slide 14 of 30
What if BP is very high? Arrange same-day admission if: o BP is 220/0mmHg or higher. o BP is 180/110mmHg or higher with signs ofaccelerated (malignant) hypertension(papilloedema and/or retinal haemorrhage). Start antihypertensives immediately if no signs of accelerated hypertension and: o Systolic BP is 180mmHg or higher,or o Diastolic BP is 110mmHg or higher. Slide 15 of 30
Diagnosis If clinic blood pressure is above 140/90mmHg -recheck blood pressure on 2 3 occasions over the next few weeks or months depending on clinical judgement. If clinic blood pressures are persistently above 140/90mmHg, offer ambulatory blood pressure monitoring If clinic BP is above or equal to: o 140/90mmHg and ABPMor HBPM is above or equal to 135/85 mmhg, diagnose stage 1 hypertension. o 160/100mmHg and ABPMor HBPM is above or equal to 150/95 mmhg, diagnose stage 2 hypertension. Slide 16 of 30
Target Organ Damage Protein in the urine Albumin:creatinine ratio Haematuria Glucose Electrolytes Creatinine and egfr Hypertensive retinopathy Serum TC and HDL ECG Slide 17 of 30
Which of the following patients can be diagnosed with hypertension? 1. A patient whose blood pressure is 140/95mmHg at ONE clinic reading Not currently, need to repeat clinic readings and then ABPM 2. A patient whose blood pressure is 140/95mmHg at one clinic reading, 145/92mmHg on a second clinic reading and 150/96mmHg at a third clinic reading - Not currently, needs ABPM 3. A patient whose blood pressure is 182/110mmHg at ONE clinic reading Yes immediate diagnosis of hypertension can be made 4. A patient whose blood pressure is over 140/90mmHg on three clinic readings and the ABPM average is 145/92mmHg Yes stage 1 hypertension 5. A patient whose blood pressure is over 160/100mmHg on three clinic readings and the ABPM average is 152/96mmHg Yes stage 2 hypertension Slide 18 of 31 MPHM13 Cardiovascular - Hypertension
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Which of these patients should receive treatment for hypertension? A patient whose blood pressure is 182/110mmHg Yes start immediately A patient whose blood pressure is 162/99mHg and has been diagnosed with stage 2 hypertension - Yes A patient whose blood pressure is 143/92mmHg and has been diagnosed with stage 1 hypertension Depends would be offered antihypertensive drug treatment if they are under 80 with one or more of the following: Target organ damage, established cardiovascular disease, renal disease, diabetes, and/or a 10 year cardiovascular risk of 20% or more. Slide 20 of 31 MPHM13 Cardiovascular - Hypertension
Lifestyle Diet Caffeine Salt Alcohol Smoking Relaxation Slide 21 of 30
Pharmacological management Slide 22 of 30
Blood Pressure Targets Under 80 years old Clinic BP target < 140/90mmHg ABPM BP target < 135/85mmHg Over 80 years old Clinic BP target <150/90mmHg ABPM BP target <145/85mmHg Slide 23 of 30
Safe, effective & appropriate use of Benefit vs Risk Drug medicines Licence, Indication, Cautions, Contraindications, Dose, Side effects, Renal/Liver impairment, Formulation, Interactions & Evidence based medicine Patient parameters Age Presenting complaint (PC) & Past medical history (PMH) Drug history drug interactions (Pharmacodynamics & Pharmacokinetics) Compliance, concordance & adherence Slide 24 of 30
Pharmacological management Slide 25 of 30
Drug Treatment Choosing drug within class Contraindications Dose and titration Monitoring and management Adverse effects Drug interactions See CKS Hypertension Prescribing information Slide 26 of 30
Follow up When starting drug treatment: Recheck BP every 4 weeks. If starting a thiazide (like) diuretic: Check urea and electrolytes, and the egfr at baseline and every 4-6 weeks. If starting an ACE inhibitor or an AIIRA: Check urea and electrolytes, and the egfr at baseline and 1-2 weeks after starting treatment. If starting a CCB no specific blood tests are required. Slide 27 of 30
Patient Perspective Estimated 50 80% of patients with hypertension do not take all of their prescribed medication Verbal advice and information on why taking medication and what may happen if doesn t Signposted to leaflets on HTN or web resources e.g. Make aware it may take several changes of drug and/or dose before optimal therapy Report side effects to prescriber or pharmacist Lifestyle changes to implement Hypertension is symptomless Slide 28 of 30
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Further Reading Clinical Knowledge Summary Hypertension NICE CG7 Hypertension Walker and Whittlesea -Clinical Pharmacy and Therapeutics - Hypertension Slide 30 of 30