Hypertension

Background

• Elevation in blood pressure that predisposes to cardiovascular disease

Epidemiology

• Based on the new American guidelines, about 40% of Americans have hypertension

Risk Factors

• Family history

Clinical Manifestations

• Usually detected on routine physical exam

History and Physical Examination

History

• Confirm the diagnosis
• Causes
  • Cardiovascular disease risk factors (smoking, obesity, exercise, family history)
  • Family history of hypertension
  • Secondary causes: age of onset, renal disease, pheo (headache, palpitations, diaphoresis), hypothyroidism, OSA (snorking daytime fatigue), drugs (OCP, NSAIDs, corticosteroids, nasal deocongestants, calcineurin inhibitors), licorice use
• Complications
  • Target organ damage: CAD, CHF, CKD, stroke, peripheral vascular disease, visual changes
• Comorbidities
  • Diabetes, dyslipidemia
• Other: routine history

Physical Examination

System	Confirm	Causes	Consequences
General		BMI, Cushing syndrome (lemon-on-toothpicks)	LOC
Vitals	Gold-standard bilateral BP	BMI
HEENT		Thyroid exam, Cushing syndrome (moon facies, buffalo hump), OSA (thick neck, retrognathia, Mallampati)	Fundoscopy for retinal hemorrhages and papilledema, carotids for bruits
CVS			LVH (displaced apex with sustained impulse, S4), CHF (JVP, S3, periphedema), PAD (shiny hairless legs)
Resp			Pulmonary edema
GI		Renal and aortic bruits, AAA, striae, abdominal obesity
MSK
Neuro			Assess for signs of stroke
Skin		Striae, ecchymoses	Shiny hairless shins

Differential Diagnosis

• White coat hypertension: check ambulatory or home BP
• Primary or essential hypertension (95%): onset 20-50 years, family history
  • Masked hypertension: check ambulatory or home BP
• Secondary hypertension (5%):
  • Very common: obesity, obstructive sleep apnoea, and medication-induced hypertension
  • Endocrine
    • Cushing syndrome
    • Conn syndrome or primary aldosteronism
    • Pheochromocytoma
    • Hypothyroidism/hyperthyroidism
    • Hyperparathyroidism
  • Renal
    • Chronic kidney disease
    • Glomerulonephritis
    • Renovascular disease, including atherosclerotic disease and fibromuscular dysplasia
  • Other
    • Obstructive sleep apnoea
    • Aortic coarctation
    • Drug- and medication-induced
      • Exogenous corticosteroids
      • Cocaine
      • Licorice
      • OCP

Secondary Hypertension

• Consider in patients with strong family history, who present with hypertensive urgency or emergency, or other clinical features
  • Drug-resistant hypertension, onset in age under 30 years, accelerated or malignant hypertension, unprovoked or excessive hypokalemia, abrupt onset, exacerbation of previously controlled hypertension, disproportionate TOD for degree of hypertension, onset of diastolic hypertension in age ≥65 years
• Approach
  • In all patients: assess for obesity and obstructive sleep apnoea, review medications, and do urinalysis/creatinine for CKD
  • If signs or symptoms: aortic coarctation (femoral-radial delay), thyroid disease, Cushing disease, pheo
  • If suspicion exists: primary aldosteronism and renal artery stenosis
    • PA especially if resistant, hypokalemia, adrenal incidentaloma
• Medications: alcohol, NSAIDS, OCP, antidepressants (MAOIs, some SSRIs and SNRIs), stimulants (including illicit drugs), corticosteroids and anabolic steroids, erythropoietin, natural licorice, herbal product (e.g. ma huang and bitter orange)

Cause	Signs and Symptoms	Screening Tests
Primary aldosteronism	cramps, weakness, low K (minotiry)	Aldo/renin ratio
Renovascular disease	aneuryms, known atherosclerosis, cardiovascular risk factors, bruit	CT angiography
Cushing syndrome	Cushingoid appearance, bruising, striae, osteoporosis, glucose intolerance, thin skin, neuropsychiatric abnormalities, hypokalemia,

Diagnosis

• Out-of-office
  • Ambulatory blood pressure monitor (gold standard), with the 24h average usually 10/10 mmHg lower than office and the daytime average 5/5 mmHg lower than office
  • Home BP monitoring (HBPM), usually 5/5 mmHg lower than office
• In-office
  • Automated office BP measurement (AOBP) ≥135/85
    • Preferred office measurement
  • Office BP measurement (OBPM), preferring electronic ≥140/90
    • Casual office BP measurement
    • Research-grade, Royal College-style office BP measurement
• Any one-time measurements ≥180/110
• Any hypertensive emergency

Management

• Rule out white coat hypertension with ABPM, if suspected

Lifestyle Changes

• Consider doing these before starting medications if patient is low risk
• Weight reduction, at least 10lbs
• Exercise 30min for 5 days weekly
• Low-sodium diet
• Restrict alcohol intake

Medications

• Thiazide, ACEi, ARB, CCB, beta-blocker, or single-pill combos (ACEi/ARB + thiazide/CCB)
  • Avoid alpha-blocker, avoid ACEi/ARB combos, and avoid beta-blockers in age >60
  • If more than 20/10 above target, start a combo pill right away
• Fewer adverse events with lower-dose combo pills than high-dose single-drug pill
• Per STITCH trial
  • Start with low-dose ACEi/thiazide or ARB/thiazide combo pill
  • Uptitrate combo pill
  • Add amlodipine
• Diabetes: prefer ACEi/ARB
• Pregnancy: see Hypertension in pregnancy

Intervention	Details	SBP/DBP
Salt reduction	100 mmol/day	-6/-2.5
Weight loss	-4.5kg	-7/-6
Alcohol reduction	-2.7 drinks/day	-5/-2
Exercise	3 times per week	-10/-7.5
Diet	DASH	-11/-5.5

Targets

• In general, lower is probably better

Population	Threshold	Target	Notes
General population or low risk	≥160/100	<140/90
Diabetes mellitus	≥130/80	<130/80
High risk (TOD or CV risk factors)	≥140/90	<140/90
High risk (SPRINT eligible)	≥130	≤120	based on AOBP
US guidelines for 10-year risk ≥10%	≥130/80	<130/80
US guidelines for 10-year risk <10%	≥140/90	<140/90

• SPRINT study
  • Included patients age ≥50 years with high risk status
    • Clinical or sub-clinical cardiovascular disease
    • CKD (non-diabetic nephropathy, proteinuria <1 g/d)
    • Framingham 10-year risk >15%
    • Age ≥75 years
  • Excluded patients with diabetes and those with resistant hypertension
  • Be careful in resistant hypertension or in frail elderly
• Pregnancy: see also Hypertension in pregnancy
• ABPM targets are 5/5 mmHg (daytime average) or 10/10 mmHg (24h average) lower than office BP targets

Drug-Resistant Hypertension

• Diagnosed based on ongoing hypertension despite at least 3 agents, including at least one diuretic
• Approach
  • Step 1: Assess adherence and perform 24-hour ABPM. Discontinue interfering drugs, rule out secondary causes, and optimize health behaviours.
  • Step 2: Optimize regimen, including switching to long-acting synergistic combinations (ACEi or ARB, DHP CCB, and thiazide-like diuretic). Simplify dosing schedule and minimize costs.
  • Step 3: Consider spironolactone 12.5 to 50 mg daily (preferred), an alpha blocker (e.g. doxazosin), or a beta blocker (e.g. bisoprolol)
  • Step 4: Consider last-line medications, including aliskiren, hydralazine, and clonidine

Further Reading

• Hypertension Canada Guidelines 2018