From the Guidelines
The workup for secondary hypertension in an overweight woman in her 40s should begin with a thorough history, physical examination, and basic laboratory tests, including a comprehensive metabolic panel, complete blood count, urinalysis, thyroid function tests, and a plasma aldosterone-to-renin ratio, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APHA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.
Initial Evaluation
The initial evaluation should focus on identifying potential secondary causes of hypertension, such as obstructive sleep apnea, primary aldosteronism, and renal artery stenosis. Given her age and weight, obstructive sleep apnea should be strongly considered, warranting screening with tools like the STOP-BANG questionnaire and potentially a sleep study.
Laboratory Tests and Imaging
Initial screening should include a comprehensive metabolic panel, complete blood count, urinalysis, thyroid function tests, and a plasma aldosterone-to-renin ratio. A 24-hour urine collection for metanephrines and catecholamines can help rule out pheochromocytoma, while renal artery imaging (duplex ultrasound, CT angiography, or MR angiography) may be appropriate to evaluate for renal artery stenosis, particularly if hypertension is severe or resistant to multiple medications, as suggested by the 2020 International Society of Hypertension global hypertension practice guidelines 1.
Consideration of Other Causes
Cushing's syndrome should be considered if she has characteristic physical features, with screening via overnight dexamethasone suppression test or 24-hour urinary free cortisol. Medication review is essential as certain drugs like NSAIDs, oral contraceptives, decongestants, and some antidepressants can elevate blood pressure.
Lifestyle Modifications
Lifestyle modifications including weight loss, sodium restriction, regular exercise, and limiting alcohol consumption should be implemented concurrently with the diagnostic workup, as these interventions may significantly improve blood pressure control regardless of the underlying cause. The ACR Appropriateness Criteria for renovascular hypertension also support the use of renal artery imaging in certain cases, such as severe or resistant hypertension 1.
From the Research
Evaluation of Secondary Hypertension
The evaluation of secondary hypertension is crucial in identifying the underlying cause of high blood pressure. According to 2, features that aid in the diagnosis of secondary hypertension include:
- Onset of hypertension before the age of 20 or after the age of 50 years
- Markedly elevated blood pressure or hypertension with severe end-organ damage
- Specific body habitus and ancillary physical findings, such as truncal obesity and purple striae in hypercortisolism
- Resistant or refractory hypertension
- Specific biochemical tests that suggest the existence of certain disorders, such as hypercalcemia in hyperparathyroidism
Common Causes of Secondary Hypertension
Common causes of secondary hypertension include:
- Renovascular disease 3
- Renal parenchymal disease 3, 4
- Primary hyperaldosteronism 3, 4, 5
- Drug and substance use 3
- Obstructive sleep apnea 3, 4, 6
- Pheochromocytoma/paraganglioma 3, 4, 5
- Cushing's syndrome 2, 3, 4, 5
- Thyroid and parathyroid conditions 3, 4
- Congenital adrenal hyperplasia 3
- Aortic coarctation 2, 3, 4
Diagnostic Approach
A combination of a good history and physical examination, astute observation, and accurate interpretation of available data is usually helpful in the diagnosis of a specific causation 2. The ABCDE mnemonic can be used to help determine a secondary cause of hypertension 6. Routine urinalysis, complete blood cell count, blood chemistry profile, and a 12-lead electrocardiogram are recommended for all patients with hypertension 6.
Considerations for Overweight Female Patients
For an overweight female patient in her 40s, it is essential to consider the potential for endocrine causes of secondary hypertension, such as primary aldosteronism and Cushing's syndrome 5. A thorough history and physical exam, including questions about concomitant medications, alcohol intake, and over-the-counter medication use, is crucial in the workup for endocrine causes of hypertension 5.