Epidemiology and pathophysiology of hypertensive retinopathy

Question 1

Why do optometrists need to
understand hypertension?

Answer 1

hypertension is asymptomatic
but there are a number of ocular
manifestations of signs which can affect visual function.
Even if there are no visual symptoms, early detection of hypertension is of value because
uncontrolled/ longstanding hypertension can have detrimental effects on a number of organs (heart, brain, kidney, peripheral circulation….).
hypertension is a major risk factor for stroke and heart attack.

Question 2

What are the common antihypertensives?

Answer 2

ACE inhibitors / A2RBs (TPR)
Calcium channel blockers (SV, TPR)
β-blockers (HR, SV, TPR)
Diuretics (SV)
α-antagonists (HR, SV, TPR)
Others e.g. methyl-dopa

Question 3

What are the risk factors and CV risk of hypertension?

Answer 3

BP
sex
age
smoking
total cholesterol
HDL cholesterol
diabetes
left ventricular hypertrophy

Question 4

What is the pathophysiology of hypertension?

Answer 4

Primary hypertension (95%) - sustained hypertension in the absence oof underlying, potentially correctable cause.
Secondary hypertension (5%) - high BP with an identified cause ~ kidney, drugs, adrenal tumour

Question 5

What is the long term risk of hypertension?

Answer 5

Cerebro-vascular disease
Coronary artery disease
Left ventricular hypertrophy (Ventricular arrhythmias, Myocardial infarction, Heart failure)
Renal failure
Retinopathy

Question 6

Hypertension and blood vessels?

Answer 6

Large arteries:
* Thickened elastic lamina
* Hypertrophied smooth muscle
* Fibrous tissue deposits
* Vessels dilate; tortuous and less compliant

Small arteries:
* Hyaline arteriosclerosis in the walls
* Narrowing of lumen
* Aneurysms
* Atheroma

Peripheral vascular disease can result from both

Question 7

Hypertension and the CNS ?

Answer 7

Cerebral haemorrhage or infarction
TIA
Encephalopathy (rare)
Papillodema

Question 8

hypertension and the retina?

Answer 8

Grade 1: arteriolar thickening, tortuousity, increased reflectiveness (“silver wiring”)
Grade 2: Grade 1 plus constriction of veins at arterial crossings (“AV nipping”)
Grade 3: Grade 2 plus evidence of retinal ischaemia (flame or blot haem, “cotton wool” exudates)
Grade 4: Grade 3 plus papilloedema

Question 9

Hypertension and the heart?

Answer 9

Coronary artery disease (angina, MI)
LVH - left ventricular hypertrophy
AF - atrial fibrilation
Heart failure
Tests: ECG, echocardiogram,
angiography

Question 10

hypertension and the kidneys?

Answer 10

Damage to renal microvasculature
Proteinuria
Renal failure
Tests: urine, urea
and electrolytes
(“U+Es”), USS, MRI

Question 11

What is the management of hypertensive retinopathy?

Answer 11

LOWER BLOOD PRESSURE (every mmHg matters)
*Refer to GP and discuss with patient.
*Lifestyle modification
*Medication (GP, cardiologist, endocrinologist)