Should a patient who has quit smoking still be on a statin (HMG-CoA reductase inhibitor)?

Statin Therapy Should Be Continued After Smoking Cessation

Yes, patients who have quit smoking should still remain on statin therapy due to their continued elevated risk of atherosclerotic cardiovascular disease (ASCVD).

Rationale for Continuing Statin Therapy

• Smoking cessation alone does not eliminate the accumulated cardiovascular risk from years of smoking, and patients who have quit smoking still maintain an elevated ASCVD risk that warrants continued statin therapy 1, 2
• The 2019 ACC/AHA guidelines specifically identify former smokers as having risk-enhancing factors that favor continuation or initiation of statin therapy, even after smoking cessation 1
• While smoking cessation improves HDL-cholesterol levels (with increases occurring rapidly after quitting), this improvement alone is insufficient to negate the need for statin therapy in patients with other risk factors 3

Risk Assessment After Smoking Cessation

• The 10-year ASCVD risk calculation should be reassessed after smoking cessation, but patients who were previously on statins will typically still have sufficient risk to warrant continued therapy 1
• Risk-enhancing factors beyond smoking status (such as family history, hypertension, diabetes, or elevated LDL-C) should be evaluated to determine the ongoing need for statin therapy 1
• Even with smoking cessation, the history of smoking remains a risk-enhancing factor that supports continued statin therapy in borderline or intermediate-risk patients 1, 2

Evidence Supporting Continued Statin Therapy

• Abrupt discontinuation of statin therapy is associated with increased risk of cardiovascular events, particularly in high-risk patients 4
• Former smokers show benefits from statin therapy including slower decline in pulmonary function, which provides additional rationale for continuing therapy 5
• The 2018 AHA/ACC Cholesterol Guidelines recommend continuing statin therapy in patients with multiple risk factors, even if one risk factor (such as smoking) has been modified 1

Special Considerations

• If the patient was initially placed on statin therapy primarily due to smoking status and has very few other risk factors, reassessment with coronary artery calcium (CAC) scoring may be considered to guide therapy decisions 1
• For patients aged 40-75 with borderline risk (5% to <7.5% 10-year ASCVD risk) after smoking cessation, CAC scoring may help determine if statin therapy can be discontinued if the score is zero 1, 6
• For patients with intermediate risk (≥7.5% to <20%), statin therapy should generally be continued even after smoking cessation unless CAC=0 and no other higher-risk conditions are present 1

Potential Risks of Statin Discontinuation

• Even brief discontinuation of statin therapy may be harmful, particularly in patients with established ASCVD risk factors 4
• The risk of statin-induced serious adverse events is very low (<0.1% for serious muscle injury and ≈0.001% for serious hepatotoxicity), supporting the favorable benefit-risk profile for continuing therapy 7
• Many perceived statin side effects may be due to nocebo/drucebo effects rather than pharmacological effects of the medication 7, 8

Follow-up Recommendations

• Reassess lipid levels and ASCVD risk factors 4-12 weeks after smoking cessation to evaluate the impact on overall cardiovascular risk 1, 2
• Continue to monitor adherence to both smoking cessation and statin therapy at regular intervals 9, 2
• Emphasize that both smoking cessation and statin therapy are complementary strategies for cardiovascular risk reduction, not substitutes for each other 1, 2

In conclusion, while smoking cessation is a critical step in reducing cardiovascular risk, it should be viewed as complementary to statin therapy rather than a replacement for it. The decision to continue statin therapy should be based on comprehensive risk assessment, with most former smokers still benefiting from ongoing statin therapy.