What is the appropriate diagnostic workup and initial management for a 58‑year‑old overweight male (BMI 31) with borderline hypertension (140/86 mmHg) presenting with several months of persistent fatigue, unchanged activity level, adequate nighttime sleep, and vague visual changes?

Diagnostic Workup for Fatigue and Visual Changes in an Overweight Hypertensive Male

This patient requires immediate screening for secondary causes of hypertension and evaluation for hypertensive end-organ damage, particularly given the combination of borderline hypertension (140/86 mmHg), obesity (BMI 31), chronic fatigue, and visual changes—which may indicate hypertensive retinopathy or other target organ complications.

Initial Laboratory Evaluation

The essential first-line workup must include 1, 2:

• Serum electrolytes (sodium, potassium) to screen for primary aldosteronism, which presents with hypokalemia, muscle weakness, and fatigue 1
• Serum creatinine with eGFR calculation to assess for renal parenchymal disease 1, 2
• Urinalysis with dipstick for proteinuria and hematuria, indicating kidney involvement 1, 2
• Fasting glucose and lipid profile to evaluate metabolic syndrome components 1, 2, 3
• Thyroid-stimulating hormone (TSH) since hypothyroidism causes fatigue, weight gain, and hypertension 1
• 12-lead ECG to detect left ventricular hypertrophy or ischemic changes 1, 2

Critical Secondary Hypertension Screening

Given this patient's presentation, specific secondary causes warrant immediate investigation 1:

Obstructive Sleep Apnea (High Priority)

• Prevalence in resistant hypertension: 25-50% 1
• The combination of obesity (BMI 31), fatigue despite adequate sleep, and hypertension strongly suggests OSA 1
• Measure neck circumference (OSA likely if >40 cm) 1
• Administer Berlin Questionnaire or Epworth Sleepiness Score 1
• Order overnight oximetry as initial screening, followed by polysomnography if positive 1

Primary Aldosteronism

• Prevalence in hypertension: 8-20% 1
• Check plasma aldosterone-to-renin ratio under standardized conditions 1
• This is particularly important if hypokalemia is present, though it can occur with normal potassium 1

Renal Causes

• Renal parenchymal disease suggested by elevated creatinine, abnormal urinalysis, or reduced eGFR <60 mL/min/1.73m² 1
• Renovascular disease should be considered if hypertension is difficult to control; order renal Duplex Doppler ultrasound 1

Hypertensive End-Organ Damage Assessment

The visual changes are a critical red flag requiring urgent evaluation 1:

Fundoscopic Examination (Mandatory)

• Perform direct ophthalmoscopy to assess for hypertensive retinopathy 1
• Look for hemorrhages, exudates, arteriovenous nicking, or papilledema 1
• Papilledema with hemorrhages/exudates indicates malignant hypertension, a medical emergency requiring immediate blood pressure reduction 1

Additional Target Organ Assessment

• Echocardiography to detect left ventricular hypertrophy with greater sensitivity than ECG, assess diastolic dysfunction 1
• Carotid ultrasound to evaluate for atherosclerotic plaques 1
• Consider brain imaging (MRI/CT) if neurologic symptoms present, as silent infarcts occur in hypertensives 1

Metabolic Contribution to Fatigue

Obesity itself is independently associated with fatigue and daytime sleepiness through metabolic mechanisms 4:

• Insulin resistance and inflammatory cytokines contribute to fatigue even without sleep apnea 4
• The interaction of metabolic disturbances with obesity is a primary determinant of subjective fatigue 4
• This underscores the importance of addressing weight and metabolic syndrome components 3, 4

Initial Management Strategy

Immediate Actions

• Confirm hypertension diagnosis with home blood pressure monitoring (≥135/85 mmHg confirms hypertension) or 24-hour ambulatory monitoring (≥130/80 mmHg) 2
• Initiate lifestyle modifications immediately: weight loss, DASH diet, sodium restriction (<2.3 g/day), increased physical activity, alcohol limitation 2, 3

Pharmacologic Treatment

• Begin combination therapy with a RAS blocker (ACE inhibitor or ARB) plus either a dihydropyridine calcium channel blocker or thiazide-like diuretic 2, 3
• Target blood pressure <130/80 mmHg given likely metabolic syndrome 2, 3
• Avoid beta-blockers initially as they may worsen fatigue and metabolic parameters 3

Critical Pitfalls to Avoid

• Do not dismiss visual changes as benign without fundoscopic examination—this could represent hypertensive emergency 1
• Do not attribute fatigue solely to poor sleep hygiene without screening for OSA, hypothyroidism, and metabolic causes 1, 4
• Do not delay secondary hypertension workup in a patient with multiple risk factors (obesity, resistant features) 1, 5
• Do not use immediate-release nifedipine if urgent blood pressure reduction is needed 6

Follow-Up Timeline

• Reassess in 2-4 weeks after initiating treatment to monitor blood pressure response and review laboratory results 2
• Complete secondary hypertension workup within 1-2 months 1, 5
• Refer to ophthalmology if retinopathy is detected on fundoscopy 1
• Refer for sleep study if OSA screening is positive 1