What is the initial evaluation and management approach for a 16-year-old female with hypertension who is not obese?

Evaluation and Management of Hypertension in a 16-Year-Old Non-Obese Female

In a 16-year-old non-obese female with hypertension, you must first confirm the diagnosis with ambulatory blood pressure monitoring (ABPM) before pursuing any workup, then conduct a focused evaluation for secondary causes given her young age and absence of obesity. 1

Initial Diagnostic Confirmation

• Obtain ABPM to confirm the diagnosis before proceeding with any laboratory or imaging studies. 1, 2 School or office readings alone are insufficient for diagnosis and lead to overtreatment of white coat hypertension. 2

• True hypertension requires mean systolic and diastolic BP ≥95th percentile on ABPM with BP load ≥25%. 1, 2

• If ABPM shows white coat hypertension (mean BP <95th percentile and load <25%), avoid unnecessary workup and simply monitor periodically. 1, 2

History and Physical Examination

Once hypertension is confirmed by ABPM, obtain a targeted history and physical examination focused on identifying secondary causes:

• Perinatal history: Prematurity, low birth weight, umbilical artery catheterization. 1

• Family history: Early-onset hypertension (suggesting monogenic causes), kidney disease, endocrine disorders. 1, 3

• Medication/substance use: Oral contraceptives, NSAIDs, decongestants, stimulants, anabolic steroids. 1

• Symptoms suggesting secondary causes: Headaches, palpitations, sweating (pheochromocytoma); muscle weakness, polyuria (hyperaldosteronism); snoring, daytime somnolence (obstructive sleep apnea). 1, 3

• Physical examination findings: Femoral pulse delay or blood pressure differential between arms and legs (coarctation of aorta); abdominal bruit (renovascular disease); cushingoid features; thyroid enlargement. 1

Laboratory and Imaging Evaluation

The absence of obesity in this patient increases the likelihood of secondary hypertension, warranting a more thorough initial workup: 3, 4

Basic Laboratory Studies (Obtain in All Confirmed Cases)

• Urinalysis (proteinuria, hematuria suggesting renal parenchymal disease). 1

• Serum creatinine and electrolytes (renal function; hypokalemia suggests hyperaldosteronism). 1

• Lipid panel (assess cardiovascular risk). 1

• Fasting glucose (assess for diabetes). 1

Secondary Cause Evaluation

In a non-obese adolescent, renal parenchymal disease and renovascular disease account for 34-79% and 12-13% of secondary hypertension cases respectively: 3

• Renal ultrasound with Doppler: First-line imaging to assess for structural renal abnormalities, discrepant kidney sizes (suggesting renovascular disease), and screen for renovascular hypertension. 1, 3 This is particularly important in non-obese adolescents where secondary causes are more likely.

• Consider plasma renin and aldosterone levels if hypokalemia is present or if there is a family history of early-onset hypertension. 1, 3

• Echocardiography should be performed if considering pharmacologic treatment to assess for left ventricular hypertrophy (LV mass >51 g/m²·⁷). 1 This helps determine urgency of treatment and provides baseline target organ damage assessment.

When to Pursue Advanced Imaging

• CTA or MRA of renal arteries if Doppler ultrasound suggests renovascular disease or if there is stage 2 hypertension, significant diastolic hypertension, or abdominal bruit. 1, 3

• Do NOT routinely obtain: Electrocardiography (not recommended for LVH screening), carotid intima-media thickness, or pulse wave velocity measurements. 1

Management Approach

Lifestyle Modifications (Initiate Immediately)

• DASH-type diet with sodium restriction and increased potassium intake. 1

• Moderate to vigorous physical activity 30-60 minutes per session, 3-5 days per week. 1

• Avoid alcohol, caffeine, and nicotine. 3

Pharmacologic Therapy Indications

Initiate antihypertensive medication if: 1

• Stage 2 hypertension is confirmed on ABPM. 1

• Left ventricular hypertrophy is present on echocardiography. 1, 3

• Symptomatic hypertension exists. 1

• Lifestyle modifications fail after 3-6 months in stage 1 hypertension. 1

First-line agents: ACE inhibitors, ARBs, long-acting calcium channel blockers, or thiazide diuretics. 1, 5 In pediatric patients 6-16 years, lisinopril has demonstrated dose-dependent efficacy starting at doses >1.25 mg (0.02 mg/kg). 6

Treatment Target

• Goal BP <90th percentile and <130/80 mmHg in adolescents ≥13 years. 1

Follow-Up Schedule

• Every 4-6 weeks if on antihypertensive medications until BP controlled. 1

• Every 3-6 months if managed with lifestyle modifications alone. 1

Critical Pitfalls to Avoid

• Do not initiate workup or treatment based on office readings alone—this leads to misdiagnosis and unnecessary medication exposure. 2

• Do not assume primary hypertension in a non-obese adolescent—the absence of obesity significantly increases the probability of secondary causes (particularly renal disease), warranting renal ultrasound as part of initial evaluation. 3, 4

• Do not delay ABPM—it is the essential first step that prevents both underdiagnosis of masked hypertension and overtreatment of white coat hypertension. 1, 2

• Do not overlook coarctation of aorta—always check femoral pulses and obtain bilateral arm blood pressures; any discrepancy warrants echocardiography. 1, 3