Essential hypertension

Question 1

How is HTN typically diagnosed?

Answer 1

By screening of an asymptomatic individual.

Question 2

Define HTN.

Answer 2

Defined as BP >140/90mmHg, with no secondary cause identified.

Question 3

Who is affected?

Answer 3

· Higher in women than in men from 65 years.

· Incidence increases with age.

Question 4

What is the pathophysiology of HTN?

Answer 4

· BP is the product of cardiac output and peripheral vascular resistance (BP = CO x PVR).
· It’s affected by preload, contractility, vessel hypertrophy and peripheral vasoconstriction.
· The pathology is from structural changes, remodelling and hypertrophy in resistance arterioles.

Question 5

What is the prognosis of HTN?

Answer 5

· Uncontrolled HTN is a major risk factor for the development of cardiac, vascular, renal and cerebrovascular disease.
· But even modest reductions in BP decrease morbidity and mortality.

Question 6

What is the aetiology of HTN?

Answer 6

· Disturbance of auto-regulation (increased vascular resistance matching an increased cardiac output). 
· Excess sodium intake.
· Renal sodium retention.
· Dysregulation of the RAAS system. 
· Increased sympathetic drive.
· Increased peripheral resistance.
· Endothelial dysfunction.
· Insulin resistance.

Question 7

List the common risk factors of HTN?

Answer 7

· Obesity. 
· Aerobic exercise <3 times per week. 
· Moderate/High alcohol intake. 
· Metabolic syndrome. 
· Diabetes mellitus. 
· Black ancestry .
· Age >60 years.
· FH of HTN or CAD. 
· Sleep apnoea.

Question 8

What are the typical signs and symptoms of HTN?

Answer 8

· Rarely have noticeable symptoms
· BP >140/90.
· Retinopathy.

Question 9

What investigations would you request if you suspected a patient had HTN?

Answer 9

· ECG. 
· Fasting metabolic panel with eGFR. 
· Fasting lipid panel. 
· Urinalysis. 
· Hb. 
· TSH.

Question 10

Why would you measure a patient’s fasting metabolic panel with eGFR?

Answer 10

May show renal insufficiency, hyperglycaemia, hypokalaemia, hyperuricaemia or hypercalcaemia.

Question 11

Why would you measure a patient’s fasting lipid panel?

Answer 11

May show high LDL, low HDL or high triglycerides.

Question 12

Why would you measure a patient’s urinalysis?

Answer 12

May show proteinuria.

Question 13

Why would you measure a patient’s Hb?

Answer 13

May show anaemia or polycythaemia - suggests secondary cause or complication.

Question 14

List some differentials.

Answer 14

· Drug-induced >>> NSAIDs, oral contraceptive pill, immunosupressants, erythropoietin.
· CKD. 
· Renal artery stenosis. 
· Aortic coarctation.
· OSA.
· Hyperaldosteronism. 
· Hypo/hyperthyroidism. 
· Cushing syndrome.

Question 15

What are the 4 steps of treatment?

Answer 15

Step 1:
· Younger than 55 and not black&raquo_space;> ACE inhibitor.
· Older than 55 or black of any age&raquo_space;> calcium channel blocker or thiazide-type diuretic.

Step 2: ACEi + calcium channel blocker or ACEi + thiazide-type diuretic (indapamide).

Step 3: ACEi + calcium channel blocker + thiazide-type diuretic.

Step 4: Step 3+ a further diuretic therapy or α-blocker or β blocker - consider seeking specialist advice.

Question 16

What should you advice the patient on as well as prescribing medication?

Answer 16

Lifestyle modifications.

Question 17

What complications can occur?

Answer 17

· CAD. 
· Cerebrovascular accident. 
· Left ventricular hypertrophy. 
· Congestive heart failure. 
· Retinopathy. 
· PAD. 
· CKD.