Essential hypertension

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The blood pressure here is incredibly high

High blood pressure. According to NICE, it has to be persistenly over 140/90mmHg.


Ridiculously high prevalence - 11.3%. 95% is primary (i.e. no known cause).


There are two types :

  • essential (aka primary or systemic) - it just happens and nobody knows the cause.
  • secondary - caused by another disease.


Nobody knows the exact cause of hypertension but there are some risk factors:

Associated Risks: Hypertension is also massively associated with cardiovascular disease which is why it is so important. It increase the risk of:

Clinical Features

The main clinical feature of high blood pressure is high blood pressure. Go figure. Well, I'm sure you did. This is about excluding secondary hypertension.


Category Systolic BP Diastolic BP
Optimal <120 <80
Normal <130 <85
High normal 130-139 85-89
Mild (grade 1) 140-159 90-99
Moderate (grade 2) 160-179 100-109
Severe (grade 3) >/=180 >/=110

Obviously, in most patients, looking to get the BP to normal is what you aim for. However, there are certain populations where you need to aim lower. Check this shizzle!

Diabetes - no nephropathy
Intervention threshold 140 90
Target levels 130 80
Diabetes - with nephropathy
Target levels 130 80
Proteinuria (<1g/24h protein in urine) 125 75
Renal disease
Intervention threshold 140 90
Target 130 80
Chronic renal disease/proteinuria 125 75


These are more appropriate if secondary hypertension is suspected. I'd look at the secondary hypertension page if I were you.


A=ACE Inhibitors; C=Calcium-Channel Blocker; and D=Thiazide Diuretic

NICE and the British Hypertension Society (BHS) each came up with a set of guidelines regarding the management of hypertension. They came up with the algorithm on the right, perhaps they drew it a little better though...

Hopefully, when to use ACE inhibitors (ramipril, lisonipril, enalapril), calcium-channel blockers (amlodipine, felodipine, nifedipine) and thiazide diuretics (usu. bendroflumethiazide) is obvious from the incredibly professionally drawn flow chart. Under the "clever other shizzle" moniker we have things like:

  • Beta blockers - atenolol, propanolol, bisoprolol
  • Angiotensin II receptor inhibitors/angiotensin receptor blocker (ARB)- losartan, irbesartan, valsartan
  • alpha blockers - doxasozin

Basically, you try different drugs until you get their blood pressure to the target levels (or you give up and refer them to a specialist).

In diabetes (both types) with nephropathy an ACE inhibitor is recommeneded (with ARBs as an alternative). The same treatment should be used in chronic kidney disease. The benefit is beyond that of simply lowering blood pressure.