Hypertension Flashcards
How many people per year die of hypertension in the USA?
1,000,000
When does blood pressure vary naturally?
Time of day
Age
Sex (women have lower BP due to hormones)
What are the diastolic hypertension criteria?
>85 = normal 85-89 = high normal 90-104 = mild hypertension 105-114 = moderate hypertension >114 = severe hypertension
What are the systolic hypertension criteria?
Less than 140 = normal
140-159 = Borderline systolic hypertension
>160 = isolated systolic hypertension
What is secondary hypertension?
Consequence of a clinical condition/ due to another pathology
What is the equation for mean arterial blood pressure?
MABP = CO x TPR (total periperal resistance)
What tends to happen to CO and tpr with age?
CO decreases
TPR increases
What are the likely causes of essential hypertension?
Cardiac dysfunction
Vessel abnormalities
Kidney dysfunction
How can cardiac dysfunction cause hypertension?
It is due to a response in stress = catecholamines
Too much CO
How do vessel abnormalities cause hypertension?
Sympathetic NS = greater innervation = abnormal = more innervation of blood vessel
Local factors eg Low endothelium derived relaxing factor and smooth muscle ion channel defects
Also muscle hypertrophy/rigidity - vascular remodelling when smooth muscle increases = increased BP
What are the known enviromental risk factors for hypertension?
Diet and obesity
Adoption of the Western lifestyle
Salt intake
Vitamin D deficiency
Which genes show the most evidence that they are linked to hypertension?
Polymorphisms in Angiotensinogen and ENaC
What can cause secondary hypertension?
Renal disease
Renal artery stenosis
Pheochromocytomas
Hormone inbalance
How can renal disease cause hypertension?
Angiotensin system is affected
Nephron function is impaired
Blood volume increases = increase in BP
If blood pressure increases the kidney may be damaged further
Tumours where can affect blood pressure and how?
On the adrenal glands
Aldosterone levels increase
