W3L1 Hypertension Flashcards
Describe the population distribution of blood pressure
Unimodal distribution, mode of SBP is around 125
Consequences of elevated blood pressure for individuals–> what does ht presispose to? (5 key conditions)
- coronary heart disease (–> infarction–> heart failure)
• stroke
• cardiac hypertrophy (heart cant relax–> increased LVEDP–> heart can’t fill properly–> HF with diastolic dysfunction)
• heart failure
• kidney failure (kidney hyperfiltration)
What is the diagnostic criteria for hypertension for normal people and diabetes/ renal dysfunction? Under what conditions and how many readings?
Otherwise normal: 140/90 mmHg
Diabetes/ renal dysfunction: 130/80 mmHg
• after 5 minutes seated at rest
• 2 readings 2 minutes apart
–> confirmed with an additional visit in 1-4 weeks, or 24 hour ambulatory measurements ehere daytime measurements were >135/85 mmHg
Outline lifestyle management of ht (5)
- Lose weight
- Improve fitness
- Avoid exces ssalt
- Moderate alcohol
- Stop smoking
What is the most common cause of resistant hypertension?How can one approach resistant ht (4th line treatment) (3)?
-poor compliance
- consider adding spironolactone, beta-blocker, centrally-actingagent, alpha-blocker or vasodilator
- check for use of NSAIDs, cold remedies, antidepressants, etc (can cause fluid retention)
- consider secondary causes
Is average BP associated with CV risk?
Yes
What is the cut off for increased CV risk and at what rate does CV risk increase?
Above 115/75 mmHg, each increase of 20mmHg SBP doubles the risk of stroke and CV events.
Do most of the deaths attributable to high BP occur in people with high or average levels of BP?
- the majority of deaths attributable to blood pressure occur in people with “normal” BP.
- modest risk in many with average BP accounts for more deaths than high risk in fewer hypertensives
How is the threshold for the diagnosis of hypertension determined?
“hypertension” coincides with a level of BP above which the benefits of treatment have been shown to outweigh the side effects.
In what % of hypertension is no specific cause identified (ie primary ht)?
95%
What are the factors that lead to primary hypertension? (2 categories, 3 factors per category)
• polygenic
– sympathetic hyperactivity
– renin activation
– susceptibility to salt
• multi-environmental
– obesity
– excess salt (especially in elderly)
– alcohol
What are the 3 ‘syndromes’ of primary hypertension and treatments therof?
preload driven: obese, peripheral oedema etc: give diuretics
cardiac: primary tachycardia: would give a calcium channel blocker (verapamil, diltiazem)/ beta blocker
afterload: obese, high vascular resistance, hard arteries.
give calcium channel inhibitors (dihydropiridines)
What are 4 examples of conditions which cause secondary hypertension (5% of hypertensives)? (7)
Renal failure (eg diabetic nephropathy, PKD, GN)
Adrenal tumours secreting: aldosterone (Conn’s syndrome), catecholamines (pheochromocytoma)
Thyrotoxicosis
Cushing’s syndrome/ disease
Renal artery stenosis
Sleep apnoea
What does isolated systolic hypertension indicate?
– generally reflects the high pulse pressure (with relatively low DBP) seen in aged and stiff arteries
What are the important features on history in hypertension? (7)
- familyhistory
- past coronary or cerebrovascular events
- heart failure symptoms
- renal disease symptoms
- smoking
- diabetes
- high cholesterol
What are the important aspects of examination in hypertension? (5)
- weight & height for BMI
- full cardiovascular examination
- fundal inspection
- renal mass or bruits
- stigmata of secondary causes
What are the important investigations to do in hypertension? ( secondary causes and outcomes) (8)
__plasmaK+ and creatinine
– high in renal disease
– low K in aldosteronism
• fasting glucose
– associated glucose intolerance
• fasting lipids
– associated CV risk
• FBE
associated anaemia of CKD
• LFTs
– associated fatty liver or drug reaction
• urine albumin/creatinine ratio
– evidence of renal damage
• MSU
– clues as to causes of renal disease
• ECG and echocardiogram
– to detect coronary disease and cardiac hypertrophy
When do you start treatment of hypertension?
- Normal person
- Associated conditions (diabetes,existing CV or renal disease)
- high CV risk
Normal:
• SBP>180mmHg OR
• DBP>110mmHg OR
• SBP>160mmHg & DBP140mmHg or DBP>90mmHg
What is classified as a high CV risk?
> 15% CV event risk over 5 y
How do we determine if a patient has high CV risk? (2)
- Risk factors, by using a heart foundation multifactorial risk chart (sex, age, SBP, smoking status, diabetes, Total:HDL cholesterol ratio)
- End organ damage:
• Microalbuminuria or low eGFR
– renal damage
• LVHypertrophy – cardiac damage
• High pulse wave velocity
– stiff large arteries
• Increased intima-media thickness
– reflects atherosclerosis
What are the 4 classes of drugs used to treat hypertension?
ACE-inhibitors/ ARBs
Beta-blockets
Ca2+ channel blockers (dihydropyridines)
Diuretics
In whom do you use ACE inhibitors/ ARBs as a step 1 treatment for ht?
People who are less than 55 years old
In whom do you use Beta blockers as as a step 1 treatment for ht?
noone
In whom do you use Ca2+ inhibitors as a step 1 treatment for ht?
> 55 years or black
