What is hypertension? Facts and figures The most common continuing medical condition seen by family doctors Not a disease but a condition that puts someone more at risk of a disease It affects 25% of the adult population & about 50% of all people over the age of 60yrs Prevalence is slightly higher in men than women: 31.5% as opposed to 29% (Health Survey for England 2010) Is one of the most preventable causes of premature morbidity and mortality world-wide (NICE 2011) Sustained blood pressure 140/90 mmHg
New NICE guidelines 2011 Changes to diagnosis Changes to treatment algorithm New targets
Measuring BP Devices must be validated, maintained and regularly recalibrated Appropriate cuff size Relaxed temperate setting, patient seated for 3-5 mins Palpate pulse first Measure BP in both arms If difference between arms is >20mmHg repeat the measurements If it remains >20mHg, measure subsequent BPs in the arm with the higher reading (Consistent inter-arm differences of >20/10mmHg warrants specialist referral) If BP is 140/90 take a second reading If the second reading is substantially different from the first take a third reading Leave a minute between each reading Record the lower of the last two readings
Check the following if reading is raised: That the person has not hurried to the session That their bladder is empty! That they havent had a large meal, alcohol, caffeine, cigarettes and exercise in previous 30 minutes Dont forget: BP rises on waking & then tends to fall through the day. BP tends to be higher in colder weather
Confirming Diagnosis If clinic BP is <140/90 review 5 yrly If clinic BP is 140/90 or higher offer ABPM to confirm diagnosis If unable to tolerate ABPM, HBPM is a suitable alternative Whilst waiting to confirm diagnosis carry out invx for target organ damage and CVD risk assessment If clinic BP 180/110 consider starting treatment immediately
ABPM – to confirm diagnosis Ensure that at least two measurements per hour are taken during the persons usual waking hours Use the average value of at least 14 measurements taken during the persons usual waking hours to confirm a diagnosis of hypertension 24hr ABPM may be required for patients who might be more at risk of non- dipping i.e. whose BP does not dip at night, as is normal. (these may be people with existing target organ damage who appear controlled and patients with Type 1 diabetes with microalbuminuria) N.B Practices who do not have their own ABPM can refer patients to Darwen or Barbara Castle HC using a D1 form
ABPM – patient information Provide patient with instructions on how to turn off and remove the device if day time only readings are required Give advice on wearing appropriate clothing i.e. allowing access to upper arm and easily removed Advise that bathing or showering is not permissible whilst the monitor is attached When the cuff tightens advise that they try to relax, and keep their arm still and at heart level if possible Warn that the monitor may repeat the measurement a minute later Advise that driving with the monitor in place is permissible but if possible try to pull over when a measurement is been taken Tell the patient to try and have a normal day!
HBPM – to confirm diagnosis For each BP recording two consecutive measurements are taken, seated, at least 1 minute apart BP is recorded twice daily, ideally morning and evening Record measurements for at least 4 days, ideally 7 days Discard measurements taken on the first day and use the average of the remaining measurements to confirm a diagnosis
HBPM – things to note Monitors should be validated and maintained Wrist monitors are not recommended and can be inaccurate but may be acceptable if the patient has had bilateral mastectomies, has sustained injuries to both upper arms or is grossly obese. Only about a third of patients fully comply with instructions Observer bias/prejudice is possible Not appropriate for patients with arrhythmias
What the readings mean (ABPM/HBPM) Daytime average <135/85mmHg Daytime average 135/85mmHg CVD risk <20%/No target organ damage Daytime average 135/35mmHg CVD risk >20% /Target organ damage Daytime average 150/90mmHg Not hypertensive- recheck BP within 5yrs Stage 1 hypertension – No treatment; reassess annually Stage 1 hypertension; treat according to NICE ACD chart Stage 2 hypertension; treat according to NICE ACD chart
NICE definitions 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 is or higher and ABPM or HBPM daytime average is 150/95 mmHg or higher. Severe hypertension: Clinic systolic BP is 180 mmHg or higher or Clinic diastolic BP is 110 mmHg or higher.
Mammen Ninan GPwSI Cardiology November 2012
Effect of systolic and diastolic BP on mortality
Event free survival and relation to night time dipping of BP
Modest reductions in SBP can substantially reduce cardiovascular mortality SBP = systolic blood pressure; CHD = coronary heart disease % Reduction in Mortality Reduction in SBP (mmHg)StrokeCHDTotal Adapted from Whelton PK, et al. JAMA 2002;288: After intervention Before intervention
Step 4 Summary of antihypertensive drug treatment Aged over 55 years or black person of African or Caribbean family origin of any age Aged under 55 years C2C2 A A + C 2 A + C + D Resistant hypertension A + C + D + consider further diuretic 3, 4 or alpha- or beta-blocker 5 Consider seeking expert advice Step 1 Step 2 Step 3 Key A – ACE inhibitor or low-cost angiotensin II receptor blocker (ARB) 1 C – Calcium-channel blocker (CCB) D – Thiazide-like diuretic See slide notes for details of footnotes 1-5
What are the key elements of effective BP control? Are your current therapy choices delivering effective control of blood pressure in all your hypertensive patients?
What is resistant Hypertension Failure to control BP to < 140/90 or <130/80 in diabetics, in spite of being on 3 different antihypertensive agents, one of which is a diuretic
Causes of Resistant Hypertension Suboptimal drug therapy White coat hypertension Coexisting conditions – esp. obesity/metabolic syndrome/OSA Antagonising substances (usually sodium) Non-compliance Coexisting medications – eg NSAIDs, OCA Unrecognised secondary causes of hypertension
Important Secondary (identifiable) Causes of Hypertension Sleep apnoea Drug induced/ related Chronic kidney disease Primary aldosteronism Renovascular disease Cushings Syndrome or steroid therapy Phaeochromocytoma Coarctation of the aorta Thyroid/ parathyroid disease
Case Study 55 year old lady comes to surgery for foot pain, she is slightly overweight with BMI of 28. Her BP was last checked 10 years ago, and you check it to satisfy QOF, and it is 158/108. Her mother had hypertension and had a stroke at the age of 70 yrs. Patient is a non smoker, works in a GP surgery as Practice Manager and admits to being stressed at work Her urine dipstick is clear, ECG does not show any signs of LVH