17.2 Antihypertensive Pharmacotherapy & Hyperlipidemia

Antihypertensive Pharmacotherapy & Teratogenic Hazards

Pharmacologic therapy is indicated for non-pregnant adults with:

• Stage 2 Hypertension (BP ≥140/90 mm Hg); OR
• Stage 1 Hypertension (BP 130–139/80–89 mm Hg) accompanied by clinical cardiovascular disease, diabetes mellitus, chronic kidney disease, or a 10-year estimated ASCVD risk ≥10%.

First-Line Antihypertensive Agents (Non-Pregnant Adults)

[!WARNING] Strict Teratogenicity of ACE Inhibitors and ARBs: Both ACE inhibitors and ARBs are classified with an FDA Boxed Warning for fetal toxicity in all trimesters of pregnancy. Exposure during the first trimester increases the incidence of major congenital cardiovascular and central nervous system malformations. Exposure during the second and third trimesters produces severe fetal renal dysgenesis, anuria, and profound oligohydramnios. Oligohydramnios precipitates the classic Potter sequence: pulmonary hypoplasia, limb joint contractures, facial compression, and neonatal renal failure, accompanied by hypocalvaria (underdeveloped skull bones) and intrauterine fetal demise. Midwives must screen all reproductive-age individuals taking ACEi or ARBs and transition them to pregnancy-safe agents prior to conception.

Preconception Antihypertensive Transition Protocol

In any individual with chronic hypertension who is contemplating pregnancy or not using reliable contraception, the midwife must proactively transition therapy to one of three validated first-line pregnancy-safe antihypertensives:

1. Labetalol: Combined alpha-1 and non-selective beta-blocker. Dosing: 100 mg PO BID, titrated up to 200–400 mg PO BID (maximum 2,400 mg/day). Avoid in patients with moderate-to-severe reactive airway disease / active asthma or second/third-degree heart block.
2. Nifedipine Extended-Release (ER): Long-acting dihydropyridine calcium channel blocker. Dosing: 30 mg PO daily, titrated up to 60–90 mg PO daily. Avoid immediate-release sublingual nifedipine (causes precipitous hypotension and fetal distress).
3. Methyldopa: Centrally acting alpha-2 adrenergic agonist. Dosing: 250 mg PO BID/TID, titrated up to 500–1,000 mg PO TID (maximum 3,000 mg/day). Extensively studied with long-term pediatric safety data, but frequently limited by maternal sedation, lethargy, depression, and elevated hepatic transaminases.

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Hyperlipidemia: Lipid Panels, ASCVD Risk & Statin Indications

Atherosclerotic Cardiovascular Disease (ASCVD) screening is an essential component of women's primary preventive health.

Fasting vs. Non-Fasting Lipid Screening

• Non-Fasting Lipid Profile: Current AHA/ACC guidelines endorse non-fasting lipid panels for routine cardiovascular risk assessment in adults. Non-fasting testing accurately quantifies total cholesterol and HDL-C, and calculates LDL-C with clinically negligible variance in non-hypertriglyceridemic individuals.
• Fasting Lipid Profile (9–12 hours fast): Mandated when non-fasting serum triglycerides are ≥400 mg/dL, when evaluating known severe familial hyperlipidemias, or prior to diagnosing pancreatitis secondary to hypertriglyceridemia.

10-Year ASCVD Risk Stratification

The AHA/ACC ASCVD Risk Estimator Plus calculates the 10-year risk of developing a first hard ASCVD event (non-fatal myocardial infarction, stroke, or coronary heart disease death) based on age (40–75 years), sex, race, systolic BP, antihypertensive use, total cholesterol, HDL-C, diabetes status, and smoking history.

• Low Risk: < 5.0% (emphasize lifestyle modifications).
• Borderline Risk: 5.0% to 7.4% (lifestyle; consider moderate-intensity statin if risk-enhancing factors present).
• Intermediate Risk: 7.5% to 19.9% (initiate moderate-intensity statin to reduce LDL-C by 30%–49%).
• High Risk: ≥ 20.0% (initiate high-intensity statin to reduce LDL-C by ≥50%).
• Risk-Enhancing Factors in Women: History of preeclampsia, gestational diabetes, premature menopause (<40 years), polycystic ovary syndrome (PCOS), systemic inflammatory conditions (rheumatoid arthritis, lupus), persistent LDL-C ≥160 mg/dL, or elevated coronary artery calcium (CAC) score.

The Four Primary Statin Benefit Groups

Per AHA/ACC guidelines, HMG-CoA reductase inhibitors (statins) are recommended for four distinct clinical populations:

AHA/ACC Statin Benefit Groups
├── 1. Clinical ASCVD (History of MI, Angina, Stroke, TIA, Peripheral Artery Disease)
│   └── High-Intensity Statin (LDL-C reduction ≥50%)
├── 2. Severe Primary Hypercholesterolemia (Baseline LDL-C ≥190 mg/dL)
│   └── High-Intensity Statin (No risk calculation required; direct initiation)
├── 3. Diabetes Mellitus in Adults Aged 40 to 75 (Baseline LDL-C 70–189 mg/dL)
│   └── Moderate-Intensity Statin (Escalate to High-Intensity if multiple ASCVD risk factors)
└── 4. Primary Prevention Aged 40 to 75 (LDL-C 70–189 mg/dL & 10-Year ASCVD Risk ≥7.5%)
    └── Moderate-Intensity Statin (High-Intensity if 10-Year Risk ≥20%)

Statin Intensity Regimens

• High-Intensity Statins (lowers LDL-C by ≥50%): Atorvastatin 40 to 80 mg daily, Rosuvastatin 20 to 40 mg daily.
• Moderate-Intensity Statins (lowers LDL-C by 30%–49%): Atorvastatin 10 to 20 mg daily, Rosuvastatin 5 to 10 mg daily, Simvastatin 20 to 40 mg daily, Pravastatin 40 to 80 mg daily.

Statin Safety, Monitoring & Preconception Cessation

• Baseline Testing: Obtain baseline ALT/AST. Routine repeat liver enzyme monitoring is no longer recommended unless the patient develops symptoms of hepatotoxicity (jaundice, right upper quadrant pain).
• Statin-Associated Muscle Symptoms (SAMS): Present in 5% to 10% of patients as bilateral proximal muscle ache, weakness, or stiffness without marked creatine kinase (CK) elevation. True rhabdomyolysis (marked CK >10 times upper limit of normal with myoglobinuria and acute renal failure) is rare (<1 per 10,000 patient-years). If severe muscle pain occurs, immediately obtain serum CK and urinalysis.
• Strict Preconception Cessation: Cholesterol is a critical substrate for fetal steroidogenesis, embryonic organ formation, and placental cell membrane stability. Statins are strictly contraindicated during pregnancy and lactation. Individuals taking statins must discontinue therapy 1 to 2 months prior to attempting conception, or immediately upon an unplanned pregnancy confirmation.

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