What is the recommended approach for diagnosing and managing a patient suspected of having hypertension?

Diagnosing Hypertension: A Structured Approach

Hypertension diagnosis requires repeated office blood pressure measurements on multiple visits (averaging the last two of three readings taken 1-2 minutes apart), confirmed by out-of-office monitoring with either ambulatory (ABPM) or home blood pressure monitoring (HBPM) when logistically feasible. 1

Blood Pressure Measurement Technique

Accurate BP measurement is foundational and requires strict adherence to protocol:

• Patient preparation: Have the patient sit quietly for >5 minutes with feet flat on floor, back supported, arm at heart level (mid-sternum), bladder emptied, and no talking during measurement 1
• Pre-measurement restrictions: No caffeine, exercise, or smoking for at least 30 minutes before measurement 1
• Cuff selection: Use validated devices with appropriate cuff size (bladder encircling 80% of arm) 1
• Measurement protocol: Take three readings 1-2 minutes apart; the patient's BP is the average of the last two readings 1
• Bilateral measurement: At the first visit, measure BP in both arms and use the higher reading arm for subsequent visits 1, 2

Diagnostic Thresholds and Confirmation Strategy

When screening office BP is 160-179/100-109 mmHg, confirm within 1 month using home or ambulatory BP measurements. 1

When BP ≥180/110 mmHg, immediately exclude hypertensive emergency before proceeding with routine evaluation. 1, 3

For BP 140-159/90-99 mmHg, diagnosis should be based on:

• Repeated office measurements on multiple visits 1
• Out-of-office confirmation with ABPM or HBPM when feasible 1

Initial Diagnostic Workup

Essential Laboratory Tests

Every newly diagnosed hypertensive patient requires:

• Complete blood count (hemoglobin, platelets) 1
• Serum creatinine with eGFR calculation (using MDRD or Cockroft-Gault formula) 1
• Serum electrolytes (sodium, potassium) 1
• Fasting lipid panel for cardiovascular risk stratification 1, 2
• Urinalysis with dipstick for protein, followed by spot urine albumin-to-creatinine ratio if dipstick negative 1
• Thyroid-stimulating hormone (TSH) 1
• Electrocardiogram to detect left ventricular hypertrophy, ischemia, or arrhythmias 1, 2

Cardiovascular Risk Assessment

Use SCORE2 for patients aged 40-69 years and SCORE2-OP for those ≥70 years to assess 10-year fatal and non-fatal CVD risk, unless already at high risk from established CVD, moderate-to-severe CKD, diabetes, or familial hypercholesterolemia. 1

Screening for Hypertension-Mediated Organ Damage (HMOD)

Cardiac Assessment

• Echocardiography is recommended when ECG shows abnormalities or when detection of left ventricular hypertrophy would influence treatment decisions 1
• Echocardiography can identify geometric patterns (concentric hypertrophy carries worst prognosis) and assess diastolic dysfunction 1

Vascular Assessment

• Carotid ultrasound may be considered for detecting asymptomatic atherosclerotic plaques in patients with documented vascular disease elsewhere 1
• Pulse wave velocity measurement for arterial stiffness assessment may be considered when available 1

Renal Assessment

• Calculate eGFR from serum creatinine (mandatory for all patients) 1
• Screen for microalbuminuria routinely in all hypertensive patients and those with metabolic syndrome 1

Fundoscopic Examination

• Perform fundoscopy when malignant hypertension is suspected or in severe hypertension 1
• Hemorrhages, exudates, and papilledema indicate severe hypertension with increased cardiovascular risk 1

Screening for Secondary Hypertension

Consider screening for secondary causes in five specific scenarios: 1

1. Early-onset hypertension (<30 years) without risk factors (obesity, metabolic syndrome, family history)
2. Resistant hypertension (BP >140/90 mmHg on three drugs including a diuretic at optimal doses)
3. Sudden deterioration in previously controlled BP
4. Hypertensive urgency or emergency
5. Strong clinical clues suggesting specific secondary causes

Approach to Secondary Hypertension

Before extensive secondary hypertension workup in resistant hypertension, first exclude pseudoresistance (poor measurement technique, white-coat effect, non-adherence) and drug/substance-induced hypertension. 1, 3

Common substances causing hypertension include:

• NSAIDs, steroids, cyclosporin 1
• Sympathomimetics, cocaine, amphetamines 2
• Decongestants 2

Targeted Testing Based on Clinical Suspicion

• Renal parenchymal disease: Kidney ultrasound, detailed urinalysis 1
• Primary aldosteronism: Plasma renin and aldosterone levels, confirmatory testing (saline suppression test), adrenal imaging 1
• Renovascular disease: Consider in younger patients with difficult-to-control hypertension 2
• Obstructive sleep apnea: Associated with resistant hypertension 2

Critical Pitfalls to Avoid

• Never diagnose hypertension based on a single office visit unless BP is severely elevated (grade 3) in a high-risk patient 1
• Do not assume well-controlled hypertension excludes complications: Hypertensive patients develop specific brain injury patterns including white matter disease and microinfarcts even with controlled BP 2
• Avoid confusing hypertensive urgency with emergency: Only the presence of acute end-organ damage defines emergency and requires immediate BP reduction 3
• Do not perform extensive secondary hypertension workup before confirming true resistant hypertension by excluding pseudoresistance 1
• Repeated measurements over time are essential: In many patients presenting with elevated BP, pressure falls considerably without medication 1