Hyperlipidemia management: A calibrated approach

Options for lipid-lowering pharmacotherapy

• Statins (formally, hydroxymethylglutaryl-coenzyme A reductase inhibitors) offer the most predictable reduction in ASCVD risk of any lipid-lowering therapy. The evidence report that accompanied the 2016 USPSTF guidelines on statins for the prevention of cardiovascular disease (CVD) stated that low- or moderate-dosage statin therapy is associated with approximately a 30% relative risk reduction (RRR) in CVD events and CVD deaths and a 10% to 15% RRR in all-cause mortality.¹⁷

High-intensity statin therapy reduces LDL-C by ≥ 50%. Moderate-intensity statin therapy reduces LDL-C by 30% to 49% (TABLE 3).⁴

Statins are not without risk: A 2016 report¹⁸ estimated that treating 10,000 patients with a statin for 5 years would cause 1 case of rhabdomyolysis, 5 cases of myopathy, 75 new cases of diabetes, and 7 cases of hemorrhagic stroke. The same treatment would, however, avert approximately 1000 CVD events among patients with preexisting disease and approximately 500 CVD events among patients at elevated risk but without preexisting disease.¹⁸

• Ezetimibe, a selective cholesterol-absorption inhibitor, lowers LDL-C by 13% to 20% and typically is well tolerated. The use of ezetimibe in ASCVD risk reduction is supported by a single randomized controlled trial of more than 18,000 patients with recent acute coronary syndrome. Adding ezetimibe to simvastatin 40 mg resulted in a 2% absolute reduction in major adverse cardiovascular events over a median follow-up of 6 years (NNT = 50), compared to simvastatin alone.¹⁹ ACC/AHA guidelines recommend adding ezetimibe to maximally tolerated statin therapy in patients with clinical ASCVD who do not reach their goal LDL reduction with a statin alone. Ezetimibe also can be considered a statin alternative in patients who are statin intolerant.⁴
• PCSK9 inhibitors. When added to statin therapy, evolocumab and alirocumab—monoclonal antibodies that inhibit PCSK9—offer an incremental decrease in LDL-C of approximately 60%.^20-22 In a meta-analysis of 35 trials evaluating the incremental benefit of PCSK9 inhibitor therapy, a significant reduction in cardiovascular events, including myocardial infarction (ARR = 1.3%; NNT = 77), stroke (ARR = 0.4%; NNT = 250), and coronary revascularization (ARR = 1.6%; NNT = 63) was reported. No significant difference was observed in all-cause or cardiovascular mortality.^21,23
• Inclisiran, an injectable small-interfering RNA that inhibits PCSK9 synthesis, provides an incremental decrease in LDL-C of > 50% in patients already receiving statin therapy. Meta-analysis of 3 small cardiovascular outcomes trials revealed no significant difference in the rate of myocardial infarction, stroke, or cardiovascular mortality with inclisiran compared to placebo. Larger outcomes trials are underway and might offer additional insight into this agent’s role in ASCVD risk management.²⁴
• Omega-3 fatty acids. Multiple trials have demonstrated that adding omega-3 fatty acids to usual lipid-lowering therapy does not offer a consistent reduction in adverse cardiovascular outcomes, despite providing a significant reduction in TG levels. In a high-risk population with persistently elevated TG despite statin therapy, icosapent ethyl, a purified eicosapentaenoic acid ethyl ester, reduced major ASCVD outcomes by 25% over a median 4.9 years (ARR = 4.8%; NNT = 21), and cardiovascular death by 20% (ARR = 0.9%; NNT = 111), compared with a mineral oil placebo.²⁵ Subsequent trials, using a corn oil placebo, failed to duplicate these data²⁶—raising concern that the mineral oil comparator might have altered results of the eicosapentaenoic acid ethyl ester study.^27,28
• Bempedoic acid is a small-molecule inhibitor of ATP citrate lyase that increases LDL uptake by the liver. Pooled data from studies of bempedoic acid show, on average, a 15% reduction in TC, a 23% reduction in LDL-C, and a 6% increase in HDL-C, without a significant change in TG.²⁹ In statin-intolerant patients, bempedoicacid reduced major ASCVD outcomes by 13% over a median 40 months (ARR = 1.6%; NNT = 63), with no significant reduction in cardiovascular death.³⁰
• Niacin. Two large trials failed to demonstrate improvement in major cardiovascular events or other clinical benefit when niacin is added to moderate-intensity statin therapy, despite a significant increase in the HDL-C level (on average, 6 mg/dL) and a decrease in the LDL-C level (10-12 mg/dL)and TG (42 mg/dL).^31,32
• Fenofibrate lowers TG and increases HDL-C but does not consistently improve cardiovascular outcomes.³³ In a trial of patients with type 2 diabetes and persistent dyslipidemia (serum TG > 204 mg/dL; HDL-C< 34 mg/dL) despite statin therapy, adding fenofibrate reduced CVD outcomes by 4.9%—although this absolute difference did not reach statistical significance.³⁴

Neither niacin nor fenofibrate is considered useful for reducing ASCVD risk across broad populations.⁴

Follow-up to assess progress toward goals

Recheck the lipid profile 4 to 12 weeks after starting lipid-lowering therapy to verify adherence to medication and assess response. The primary goal is the percentage reduction in LDL-C based on ASCVD risk. An additional goal for very-high-risk patients is an LDL-C value ≤ 70 mg/dL. If the reduction in LDL-C is less than desired and adherence is assured, consider titrating the statin dosage or augmenting statin therapy with a nonstatin drug (eg, ezetimibe), or both.⁴ ●

CORRESPONDENCE

Jonathon M. Firnhaber, MD, MAEd, MBA, East Carolina University, Family Medicine Center, 101 Heart Drive, Greenville, NC 27834; firnhaberj@ecu.edu