Essential Hypertension
Chronic high blood pressure with no single clear cause, significantly increasing the risk of heart attacks and strokes.
Emergency Management: Hypertensive Emergency: Severe BP elevation with acute target organ damage (e.g., aortic dissection, encephalopathy). Requires IV medications (Nicardipine, Labetalol) to lower BP by max 25% in the first hour.
Essential hypertension is a chronic medical condition characterized by persistently elevated systemic arterial blood pressure without an identifiable secondary cause. It is the most common cardiovascular disease and a major risk factor for stroke, myocardial infarction, and chronic kidney disease.
Detailed Overview
Often termed the "silent killer," essential hypertension typically produces no symptoms until target organ damage occurs. It accounts for 90-95% of all hypertension cases. The condition is mediated by a complex interplay of genetic, environmental, and lifestyle factors leading to increased systemic vascular resistance and altered renal sodium handling. Lifelong management with lifestyle modifications and pharmacotherapy is required.
Epidemiology & Demographics
Affects nearly 46% of adults in the United States. Prevalence increases sharply with age. Higher prevalence and severity in African American populations. Lifetime risk for adults over 45 is 90%.
Etiological Mechanism
Idiopathic. It is a polygenic trait interacting with environmental exposures.
Primary Causes
No single distinct cause, but heavily influenced by high dietary sodium, obesity, insulin resistance, and sympathetic nervous system overactivity.
Blood pressure is the product of cardiac output and systemic vascular resistance (SVR). In essential hypertension, SVR is uniformly elevated. This occurs due to 1) Sympathetic Nervous System overactivity causing peripheral vasoconstriction and tachycardia. 2) Overactivation of the Renin-Angiotensin-Aldosterone System (RAAS), where excess Angiotensin II causes direct vasoconstriction and Aldosterone drives renal sodium and water retention. 3) Endothelial dysfunction, characterized by an imbalance between vasodilators (nitric oxide) and vasoconstrictors (endothelin). 4) Defective renal pressure natriuresis, forcing the kidney to require higher systemic pressures to excrete a given sodium load. Chronically elevated pressure causes vascular remodeling (arteriolosclerosis), left ventricular hypertrophy, and glomerular damage.
Diagnostic Criteria & Guidelines
Diagnosis requires properly measured seated blood pressure resting for 5 minutes, showing elevated BP on >= 2 distinct occasions. AHA/ACC 2017 criteria define hypertension as BP >= 130/80 mmHg. Out-of-office measurements (Ambulatory BP monitoring) are recommended to confirm diagnosis.
Lifestyle modifications for all. Pharmacotherapy initiated based on Stage and ASCVD risk. First-line classes include: 1) Thiazide diuretics (Chlorthalidone 12.5-25 mg PO daily), 2) Calcium Channel Blockers (Amlodipine 5-10 mg PO daily), 3) ACE inhibitors (Lisinopril 10-40 mg PO daily) or ARBs (Losartan 50-100 mg PO daily).
Second-Line & Adjunctive Therapy
Combination of two first-line agents from different classes (e.g., Amlodipine + Lisinopril). For resistant hypertension (BP uncontrolled on 3 drugs including a diuretic), add Spironolactone 25 mg PO daily.
Surgical & Procedural Management
N/A for essential hypertension. (Renal sympathetic denervation is experimental).
Patient Counseling & Advice
Explain that they will likely feel no different when their BP is high vs. controlled, but taking medication daily prevents strokes and heart attacks years down the line.
Follow-Up & Monitoring Schedule
Recheck BP in 1 month after initiating or changing medication. Once at target (<130/80), monitor every 3-6 months. Annual check of serum creatinine, potassium, and lipids.
Preventive Strategies
Maintenance of normal body weight, regular exercise from a young age, and population-level reductions in dietary sodium.
Excellent with strict adherence to therapy. Untreated, it shortens life expectancy by 10-20 years, mostly through cardiovascular mortality.