When should a statin be started for primary prevention of cardiovascular disease?

When to Start Statin Therapy for Primary Prevention of Cardiovascular Disease

Statins should be initiated for primary prevention in adults aged 40-75 years with one or more cardiovascular risk factors (dyslipidemia, diabetes, hypertension, or smoking) and a 10-year ASCVD risk of 10% or greater. 1, 2

Primary Prevention Recommendations Based on Risk Assessment

High Risk Individuals (Strong Recommendation for Statin Therapy)

• Adults aged 40-75 years with LDL-C ≥190 mg/dL should receive maximally tolerated statin therapy regardless of calculated risk 2
• Adults aged 40-75 years with diabetes should receive at least moderate-intensity statin therapy regardless of calculated risk 2, 3
• Adults aged 40-75 years with 10-year ASCVD risk ≥10% and one or more CVD risk factors should receive moderate-intensity statin therapy 2, 1
• Adults aged 40-75 years with 10-year ASCVD risk ≥20% should be considered for high-intensity statin therapy to reduce LDL-C by ≥50% 2, 3

Intermediate Risk Individuals (Consider Statin Therapy)

• Adults aged 40-75 years with 10-year ASCVD risk of 7.5% to <10% and one or more CVD risk factors may be offered moderate-intensity statin therapy after shared decision-making 2
• For intermediate-risk patients (7.5% to <20% 10-year risk), the presence of risk-enhancing factors favors initiation of statin therapy 2
• Coronary artery calcium (CAC) scoring can help decision-making in intermediate-risk patients:
  • CAC score of zero: reasonable to withhold statin therapy and reassess in 5-10 years 2
  • CAC score 1-99: consider statin therapy for patients ≥55 years 2
  • CAC score ≥100 or ≥75th percentile: initiate statin therapy 2

Borderline Risk Individuals

• Adults aged 40-75 years with 10-year ASCVD risk of 5% to <7.5% may be considered for statin therapy if risk-enhancing factors are present 2

Statin Intensity Recommendations

• High-intensity statin therapy (reduces LDL-C by ≥50%):

  • Preferred for patients with 10-year ASCVD risk ≥20% 2, 3
  • Recommended for patients with LDL-C ≥190 mg/dL 2
  • Reasonable for diabetic patients with multiple ASCVD risk factors 2

• Moderate-intensity statin therapy (reduces LDL-C by 30% to <50%):

  • Recommended for most primary prevention patients with 10-year risk ≥7.5% 2
  • Recommended for all adults aged 40-75 with diabetes 2

Special Populations and Considerations

• Adults >75 years: Evidence is insufficient to determine the balance of benefits and harms of initiating statin therapy for primary prevention 2, 1
• Patients with severe hypercholesterolemia (LDL-C ≥190 mg/dL) have high risk of ASCVD and should receive maximally tolerated statin therapy 2
• In diabetic patients with multiple ASCVD risk factors, high-intensity statin therapy is reasonable to reduce LDL-C by ≥50% 2

Potential Pitfalls and Caveats

• Statin underutilization remains a significant issue, with up to 92.8% of eligible individuals with LDL-C ≥190 mg/dL and 74.6% with intermediate ASCVD risk plus enhancers not receiving appropriate statin therapy 4
• Social determinants of health, including lack of healthcare access and insurance coverage, are associated with lower rates of statin prescription 4
• The 2022 USPSTF recommendations are more conservative than the 2018 ACC/AHA guidelines, potentially leaving approximately 16 million fewer adults eligible for statin therapy 5
• Long-term benefit approaches to statin eligibility may identify younger individuals with higher LDL-C levels who would benefit from treatment but are not currently recommended under risk-based approaches 6

Monitoring After Initiation

• LDL-C levels should be assessed 4-12 weeks after initiating therapy to evaluate response and adherence 3
• The magnitude of LDL-C reduction achieved determines clinical benefit 3, 2
• Follow-up testing is needed to determine adherence and adequacy of effect of the statin prescribed 3, 2

By following these evidence-based recommendations, it's estimated that approximately 1 million ASCVD events could be prevented over 10 years if all statin-eligible individuals received appropriate treatment 4.