Hypertension
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"hypertension" AND "management"
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That block was about PAD. Let me find the dedicated Hypertension chapter in the Family Medicine textbook.
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I can see block7 has the main hypertension chapter with definition, risk factors, assessment, and secondary HTN. Let me read those sections in parallel.
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Hypertension
Definition and Prevalence
Hypertension (HTN) is defined as a persistently elevated blood pressure (BP) of 140 mm Hg or greater systolic (SBP) or 90 mm Hg or greater diastolic (DBP). It affects roughly one-third of adults in the United States and at least one-quarter of adults worldwide. Undertreatment remains a major problem - only about 50% of people in the US achieve BP goals.
A BP above 115/75 mm Hg is a well-established risk factor for:
- Coronary artery disease (CAD) and myocardial infarction (MI)
- Left ventricular hypertrophy (LVH) and congestive heart failure (CHF)
- Peripheral artery disease (PAD) and aneurysmal disease
- Stroke (approximately half of all strokes worldwide are attributable to HTN)
- Chronic kidney disease (CKD) and sudden death
HTN is the single leading cause of morbidity worldwide (Global Burden of Disease Study). Every 20/10 mm Hg elevation in BP leads to an approximate doubling of risk of death from ischemic heart disease and other vascular causes.
Classification (JNC 7 / JNC 8)
| Category | SBP (mm Hg) | DBP (mm Hg) |
|---|---|---|
| Normal | < 120 | < 80 |
| Prehypertension | 120-139 | 80-89 |
| Stage 1 HTN | 140-159 | 90-99 |
| Stage 2 HTN | ≥ 160 | ≥ 100 |
| Hypertensive Crisis | > 180 | > 120 |
Even "pre-hypertension" (120-139/80-89 mm Hg) is associated with an approximate doubling of cardiovascular risk.
Blood Pressure Measurement
Proper technique is mandatory:
- Office BP: Patient seated, arm at heart level, 5 minutes of rest, two readings averaged
- Home BP goal: < 135/85 mm Hg (averages)
- 24-hour ambulatory BP goal: < 130/80 mm Hg
- White-coat HTN (elevated in office, normal at home) and masked HTN (normal in office, elevated at home) must be considered - home BP monitoring helps differentiate
Risk Factors
Non-modifiable:
- Age (risk increases with age; SBP is more important than DBP after age 50)
- Family history / genetics
- Race (higher prevalence and severity in Black populations)
Modifiable:
- Obesity / overweight
- High sodium intake
- Physical inactivity
- Excessive alcohol
- Smoking
- Diabetes mellitus / insulin resistance
Etiology
Primary (Essential) HTN - accounts for ~95% of cases. Multifactorial; involves increased vascular resistance, renin-angiotensin-aldosterone (RAAS) activation, sympathetic nervous system activation, sodium retention, and genetic factors.
Secondary HTN - accounts for ~5% of cases. Consider in younger patients, resistant HTN, or with clinical clues:
| Cause | Clue |
|---|---|
| Primary hyperaldosteronism | Hypokalemia, low renin |
| Renal artery stenosis | Abdominal bruit, renal insufficiency, flash pulmonary edema |
| Chronic kidney disease | Elevated creatinine, proteinuria |
| Obstructive sleep apnea | Obesity, snoring, daytime sleepiness |
| Pheochromocytoma | Episodic headache, sweating, palpitations |
| Hypothyroidism/Hyperthyroidism | Thyroid dysfunction symptoms |
| Coarctation of aorta | Arm-leg BP differential, rib notching |
| Cushing's syndrome | Centripetal obesity, striae |
Workup / Evaluation
Minimum initial evaluation includes:
- History: Duration, prior BP readings, symptoms, medications (NSAIDs, OCP, decongestants, stimulants), family history
- Physical exam: BMI, fundoscopic exam, cardiac exam, abdominal bruits, peripheral pulses
- Labs: Urinalysis, BMP (electrolytes, creatinine, glucose), fasting lipid panel, CBC
- ECG: Screen for LVH, arrhythmias
Treatment
BP Goals
| Population | Goal BP |
|---|---|
| General adults < 60 years | < 140/90 mm Hg |
| Adults ≥ 60 years (JNC 8) | < 150/90 mm Hg |
| Diabetes or CKD | < 140/90 mm Hg |
| Home BP goal | < 135/85 mm Hg |
Lifestyle Modifications (first-line for all stages)
- DASH diet (high fruit/vegetable, low sodium, low saturated fat)
- Sodium restriction: < 2,400 mg/day (ideally < 1,500 mg/day)
- Weight loss (each kg lost lowers SBP ~1 mm Hg)
- Regular aerobic exercise (30 min most days)
- Limit alcohol (≤ 2 drinks/day men; ≤ 1 drink/day women)
- Smoking cessation (reduces overall CV risk)
Pharmacotherapy
When to start: Stage 1 HTN with high CV risk or failed lifestyle modification; all Stage 2 HTN.
If BP is > 20/10 mm Hg above goal, strongly consider starting two antihypertensive medications (combination pill). Most patients (~75%) will require two or more drugs.
First-line Drug Classes
| Class | Examples | Notes |
|---|---|---|
| ACE Inhibitors | Lisinopril, enalapril, ramipril | First-line for diabetes, CKD, CHF, post-MI; avoid in pregnancy |
| ARBs | Losartan, valsartan, olmesartan | Alternative to ACEi if cough; same compelling indications |
| Calcium Channel Blockers (CCB) | Amlodipine (dihydropyridine); diltiazem, verapamil (non-DHP) | Excellent combination partner with ACEi; reduces CCB edema |
| Thiazide Diuretics | Chlorthalidone (preferred), hydrochlorothiazide | Chlorthalidone is longer-acting and more potent; underutilized |
Best Combination (per ACCOMPLISH trial)
ACE inhibitor + CCB (amlodipine) is preferred first-line combination. ACE inhibitor + thiazide diuretic is an acceptable alternative.
Avoid
- Double RAAS blockade: ACEi + ARB, or ARB + renin inhibitor - almost always contraindicated
- Beta-blockers as first-line (inferior stroke prevention; not first-line unless compelling indication like CAD, CHF, arrhythmia)
- Alpha-blockers as first-line (inferior vs. other agents in clinical trials)
Compelling Indications (match drug to comorbidity)
| Comorbidity | Preferred Agent(s) |
|---|---|
| CHF / reduced EF | ACEi (or ARB) + beta-blocker + aldosterone antagonist |
| Post-MI | ACEi + beta-blocker |
| Diabetes with proteinuria | ACEi or ARB |
| CKD with proteinuria | ACEi or ARB |
| Recurrent stroke prevention | ACEi + thiazide |
| Stable angina | Beta-blocker or CCB |
Special Situations
Resistant Hypertension
- Defined as BP above goal on 3 or more appropriately dosed agents (including a diuretic)
- Affects ~10% of hypertensive patients
- Add spironolactone 25-50 mg/day (empirical aldosterone blockade) - effective in many cases
- Consider referral to HTN specialist
- Evaluate for secondary causes
Hypertensive Crisis
| Type | BP | Organ Damage? | Management |
|---|---|---|---|
| Urgency | > 180/120 | No | Oral agents, reduce over 24-48h |
| Emergency | > 180/120 | Yes (brain, heart, kidneys) | IV agents (nitroprusside, labetalol, nicardipine), ICU; reduce by ~25% in first hour |
Hypertension in Pregnancy
- Gestational HTN: BP ≥ 140/90 after 20 weeks, no proteinuria
- Preeclampsia: HTN + proteinuria ± end-organ damage
- Safe medications: Methyldopa, labetalol, nifedipine
- Avoid: ACEi, ARBs (teratogenic)
Hypertension in Elderly
- Systolic HTN predominates; isolated systolic HTN is common
- SBP more predictive of CV risk than DBP after age 50
- Treatment still beneficial; JNC 8 allows goal < 150/90 in ≥ 60 years
Therapeutic Inertia and Adherence
Common barriers to control:
- Under-aggressive dosing / infrequent follow-up
- Underuse of chlorthalidone (longer-acting, more potent thiazide)
- Withholding ACEi/ARBs in mild-moderate renal insufficiency (a mistake - a 30-40% creatinine rise is acceptable if it stabilizes; monitor for hyperkalemia)
- Under-prescribing of CCBs due to fear of edema (combining with low-dose ACEi reduces edema)
- Beta-blocker overuse in primary prevention settings
- Poor patient education and non-adherence
Key Takeaways
- HTN is the leading cause of morbidity worldwide - identify and treat early
- Lifestyle changes are first-line for all patients
- Most patients need 2+ medications; start combination therapy if > 20/10 above goal
- Match drug to comorbidity (compelling indications)
- Preferred combination: ACEi + amlodipine (ACCOMPLISH evidence)
- Never combine two RAAS blockers
- For resistant HTN, add spironolactone
- Always check for secondary causes when HTN is resistant or onset is atypical
Sources: Textbook of Family Medicine 9e; Pfenninger and Fowler's Procedures for Primary Care 3e; Brenner and Rector's The Kidney
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