Hypertension

• tunica intima = endothelium of blood vessels

  tunica media = muscle of blood vessels
• Central control of blood pressure is via the neuroendocrine system. Impaired neural control or in a pathological state endocrine control takes over and regulates BP via adrenaline, angiotensin and vasopressin
• Secondary hypertension is where there is an identifiable singular cause. Removal or reversal of this cause leads to normalisation of BP. Main causes of secondary hypertension are primary hyperaldosteronism , obstructive sleep apnoea and obesity
• Risk factors for primary hypertension include: old age, raised BMI, increased salt intake, alcohol and smoking
• A BP reading of 140/90 to 160/100 in the clinic or 135/85 to 150/95 at home is stage 1 hypertension
• White coat hypertension is a condition where a person's blood pressure is elevated in a clinical setting but normal in other settings.
• A BP reading of 160/100 to 180/120 in the clinic or > 150/95 at home is stage 2 hypertension
• A systolic BP >180 or diastolic BP >120 is a hypertensive crisis
• If BP > 140/90 in clinic offer ABPM or HBPM to confirm diagnosis. While waiting for results investigate organ damage and cardiovascular risk.
• Investigations for hypertension:

  Haematuria and urine albumin:creatinine ratio to assess for kidney damage

  HbA1C

  Electrolytes, creatinine and eGFR to assess for CKD

  examine fundi for hypertensive retinopathy

  12 lead ECG

  Assess cardiovascular risk with lipid profile and QRISK3
• Complications of hypertension include: damage to heart and coronary arteries, stroke, kidney damage and vision loss
• Treatment of hypertension with T2DM or age <55 not of black ethnicity:

  1. ACEi or ARB
  2. ACEi or ARB + CCB or thiazide like diuretic
  3. ACEi or ARB + CCB + thiazide like diuretic
  4. consider seeking expert advice or adding spironolactone / beta blocker
• Treatment of hypertension >55yrs or of black ethnicity:

  1. CCB
  2. CCB + ACEi or ARB or thiazide like diuretic
  3. ACEi or ARB + CCB + thiazide like diuretic
  4. consider expert advice or add spironolactone/ beta blocker
• Any patient under the age of 40 with a new hypertension should be referred to secondary care
• Patient in hypertensive crisis with a headache, chest pain and vision changes need to be referred to hospital
• ACE inhibitors prevent proteinurea. any patient starting this drug or increased dose needs their U&Es repeating.
• patients starting an ACE inhibitor need to be informed about sick days. If they develop diarrhoea and vomiting they need to pause the medication until symptoms resolve to prevent AKI.
• Spironolactone increases potassium
• Amlodopine is the most likely CCB to cause oedema
• Endocrine causes of secondary hypertension:

  • Primary aldosteronism
  • Phaechromocytoma
  • Cushing's syndrome
  • Acromegaly
• Renal causes of secondary hypertension:

  • Renal artery stenosis
  • Polycystic kidney
  • Renovascular disease
  • Intrinsic renal disease e.g. CKD, glomerulonephritis
• Drugs that cause hypertension:

  • Glucocorticoids
  • Oral contraceptives
  • SSRIs
  • NSAIDs
  • EPO
• Consider coarctation of the aorta as a cause of hypertension in children or young adults