Primary Hypertension Prevalence
Primary (essential) hypertension accounts for approximately 90% of all hypertension cases, making it by far the most common form of elevated blood pressure. 1
Epidemiologic Distribution
The distinction between primary and secondary hypertension is fundamental to understanding hypertension prevalence:
Primary hypertension represents 90-95% of all hypertension cases in the general population, with no identifiable underlying cause. 1, 2
Secondary hypertension accounts for only 5-10% of cases in unselected hypertensive populations, though this proportion increases substantially in specific clinical contexts. 2, 3
The 2024 European Society of Cardiology guidelines confirm that approximately 90% of hypertension results from complex interactions between genetic predisposition, environmental factors, and multiple organ systems, defining the scope of primary hypertension. 1
Context-Dependent Variations
The prevalence of primary versus secondary hypertension shifts dramatically based on clinical presentation:
In resistant hypertension populations, secondary causes increase to 10-35% of cases, meaning primary hypertension still represents 65-90% even in this challenging subset. 4
Among patients with severe hypertension (BP >180/110 mmHg), secondary causes like primary aldosteronism may account for up to 13%, but primary hypertension remains the majority. 4
In malignant hypertension presentations, secondary causes are found in 20-40% of cases, with primary hypertension still representing 60-80%. 1
Global Burden
The worldwide impact of primary hypertension is substantial:
An estimated 1.39 billion adults (31.1% of the global adult population) had hypertension in 2010, with the vast majority having primary hypertension. 5
The prevalence is higher in low- and middle-income countries (31.5%) compared to high-income countries (28.5%), though primary hypertension remains the dominant form in both settings. 5
Clinical Implications
Understanding this distribution is critical for clinical practice:
Routine screening for secondary causes in all hypertensive patients is not cost-effective given that 90-95% have primary hypertension. 2
Evaluation for secondary causes should be reserved for specific clinical scenarios: onset before age 20 or after age 50, resistant hypertension requiring ≥3 medications, severe end-organ damage, or specific biochemical abnormalities like unprovoked hypokalemia. 2, 3
The 2024 ESC guidelines recommend referral to specialized centers only for patients with suspected resistant hypertension or clear indicators of secondary causes, acknowledging that most patients have primary disease. 4