When do you start cholesterol medications, such as atorvastatin (lipitor) or simvastatin, in patients with hyperlipidemia?

When to Start Cholesterol Medications

Cholesterol-lowering medications should be initiated based on ASCVD risk assessment, with statins started in adults 40-75 years with LDL-C ≥70 mg/dL and a 10-year ASCVD risk ≥7.5% after a clinician-patient risk discussion. 1

Primary Prevention: Risk-Based Approach

Adults 40-75 Years Without Existing ASCVD:

1. Calculate 10-year ASCVD risk and assess LDL-C levels

   • High risk (≥20% 10-year risk): Start statin to reduce LDL-C by ≥50%
   • Intermediate risk (7.5-19.9% 10-year risk): Start moderate-intensity statin if risk discussion favors therapy
   • Borderline risk (5-7.5% 10-year risk): Consider statin if risk-enhancing factors present 1

2. Risk-enhancing factors that favor statin initiation:

   • Family history of premature ASCVD
   • Persistently elevated LDL-C ≥160 mg/dL
   • Metabolic syndrome
   • Chronic kidney disease
   • History of preeclampsia or premature menopause
   • Chronic inflammatory disorders
   • High-risk ethnic groups
   • Persistent elevations of triglycerides ≥175 mg/dL
   • Elevated apolipoprotein B, high-sensitivity C-reactive protein, or lipoprotein(a) 1

3. When uncertain about statin therapy (intermediate risk):

   • Consider coronary artery calcium (CAC) score
   • If CAC = 0: May withhold or delay statin (except in smokers, diabetics, or strong family history)
   • If CAC = 1-99: Favors statin therapy, especially in those ≥55 years
   • If CAC ≥100 or ≥75th percentile: Statin indicated 1

Special Populations:

• Diabetes mellitus: Start statin therapy, especially in those with multiple risk factors or age 50-75 years 1
• Familial hypercholesterolemia: Start statin without calculating 10-year risk 1
• Children/adolescents: For familial hypercholesterolemia, consider statins after age 10 in boys and after menarche in girls 1

Secondary Prevention (Existing ASCVD)

• All patients with clinical ASCVD: Start high-intensity statin therapy 1
• Very high-risk ASCVD patients: If LDL-C ≥70 mg/dL despite maximally tolerated statin therapy, consider adding PCSK9 inhibitor 1
• Post-ACS: Initiate high-dose statin as early as possible during hospitalization 1

LDL-C Treatment Goals

1. Without ASCVD or major risk factors: LDL-C <2.5 mmol/L (<100 mg/dL)
2. With imaging evidence of ASCVD or major risk factors: LDL-C <1.8 mmol/L (<70 mg/dL)
3. With clinical ASCVD: LDL-C <1.4 mmol/L (<55 mg/dL) 1
4. Recurrent ASCVD events within 2 years on maximally tolerated statin: Consider LDL-C <1.0 mmol/L (<40 mg/dL) 1

Monitoring After Starting Therapy

• Check LDL-C levels 4-12 weeks after initiating therapy or dose changes 2
• Measure liver enzymes, creatinine, and glucose at baseline 1
• Do not routinely monitor creatine kinase unless muscle symptoms develop 2
• Ask about muscle symptoms at each follow-up visit 2

Common Pitfalls to Avoid

1. Inadequate follow-up: Missing the 4-12 week initial check can delay necessary dose adjustments 2
2. Premature discontinuation: Stopping therapy leads to loss of cardiovascular benefit 2
3. Ignoring adherence issues: Poor adherence is a common cause of suboptimal LDL response 2
4. Overlooking drug interactions: Be aware of medications that increase myopathy risk (cyclosporin, macrolides, azole antifungals, some calcium antagonists, HIV protease inhibitors) 1
5. Diabetes risk: High-intensity statins may increase risk of new-onset diabetes (36% relative increase), particularly important to monitor in predisposed patients 1

Remember that the decision to start cholesterol-lowering medication should involve a clinician-patient risk discussion covering major risk factors, potential benefits, possible adverse effects, and patient preferences before initiating therapy.