Hypertension Flashcards
Define hypertension.
hypertension is that blood pressure at which the benefits of treatment with antihypertensive agents in reducing cardiovascular, cerebrovascular and peripheral vasculaer risk outweigh’s the risk of treatment
BP 140/90
Describe the aetiology of hypertension
Polygenic
- major genes (single genes abnormalities )
- poly genes (multiple genes involved).
- There are >30 genes recognized as important but they individually account for at most 0.5mmHg each
Polyfactorial
- Environment
- individual and shared
What are the stages of hypertension
Stage 1 Hypertension
- Clinic BP 140/90 or higher
- ABPM daytime average 135/85 mmHg or higher
Stage 2 Hypertension
- Clinic BP 160/100 or higher
- ABPM daytime average 150/95 mmHg or higher
Stage 3 or severe Hypertension
- Clinic systolic BP 180/120mmHg or higher
Risk from hypertension is associated with other risk factors, what are they?
- Cigarette smoking
- Diabetes 5-30 x increase of MI
- Renal disease
- Male - 2X risk
- Hyperlipidaemia
- Previous storke/MI
- LV hyperterphophy - 2x risk
Recognise the effectiveness of treatment for hypertension in both the young and elderly population
STAGE 1 HYPERTENSION TREATMENT
- Offer antihypertensive drug treatment to people <80 years with on or more of the following
~ Target end organ damage
~ Established cardiovascular disease
~ Renal disease
~ Diabetes
~ 10 year CV risk 10% or greater - If <40 with stage I hypertension –
~ Seek specialist evaluation for secondary causes of hypertension and a more detailed assessment of potential end organ damage - Elderly patients
~ Offer the same antihypertensive drug treatment as age 55-80 (taking into account any co-morbidieties) but BP target of 145/85
STAGE 2 HYPERTENSION TREATENT
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension
Discuss the stepped approach to the treatment of hypertension
- Confirm diagnosis
- Assess risk factors
- Assess end organ damage
What are the strengths and weaknesses of antihypertensive therapy
Discuss the treatment of hypertension occurring during pregnancy
Use of a centrally acting agent such as METHYLDOPA
What are the likely causes of hypertension?
Increased reactivity of resistance vessels and resultant increase in peripheral resistance
- Hereditary defect of the smooth muscle lining of arterioles
A sodium homeostatic effect
- In hypertensive individuals, the kidneys are unable to excrete appropriate amounts of sodium for any given BP (Pressure naturesis). As a result sodium and fluid are retained and the BP increases
What are some other factors that contribute to hypertension
- Age (BP tends to rise with age)
- Genetics and family history (hypertension tend to run in families)
- Environment (mental and physical stress > BP)
- Weight (obese patients have a higher BP)
- Alcohol Intake (one of most common causes of hypertension in young men)
- Race (Africans tend to have higher BP than caucasians)
Screen for treatable causes
Most common in younger patients
- Obesity
- Renal artery stenosis/ fibromuscular dysplasia
- Endocrine causes
- Coarctation of aorta
- Drug induced
- Sleep apnoea
What is STEP 1 in choosing a antihypertensive drug treatment
- Aged over 55 or Black people of African/Caribbean descent
- Start a calcium channel blocker or a thiazide like diuretic
- Aged Under 55 –
- offer ACE inhibitor or ARB
- Not African or Caribbean – less effective and higher risk of angioedema
- Women of child bearing age – teratogenic in early stages and fetal toxic in later stages
- offer ACE inhibitor or ARB
What is STEP 2 in choosing a antihypertensive drug treatment
- Add Thiazide type diuretic to step 1
- Eg Indapamide
What is step 3 in choosing a antihypertensive drug treatment
- Add CCB, ACEi and diuretic together
What is step 4 in choosing a antihypertensive drug treatment
- Unable to achieve target BP despite 3 or more agents
- Consider compliance issues
- Consider high dose thiazide like diuretic therapy (if K+>4.5)
- Consider further diuretic therapy
- low dose spironolactone
