We're back to continue the discussion about reducing the risk of heart attack and stroke. Last week, we spoke about lipid testing. Lipid testing is only one part of global CVD risk estimation. It can be performed no more than every 5 years but can be repeated sooner if other CVD risk factors develop in the interim.
Our message this week: Overall risk, not lipid levels, is the best predictor of benefit from statins.
Estimating risk without a risk assessment tool is challenging; both patients and clinicians frequently err in their estimations. An over-reliance on lipid levels and lack of appreciated risk might contribute to why many high-risk patients go without treatment. Additionally, estimation of risk promotes shared, informed decision making, allowing a discussion with patients about their baseline risk and, as a result, the potential absolute benefit of taking a statin.
Risk can be calculated using a number of risk calculators but each clinician should use the same one consistently
. The Framingham calculator has been validated in a Canadian population and is likely preferred. Check out our Quick Links section for an easy-to-use, digital calculator you can bookmark on your computer.
Evidence is lacking for the use of particular targets to guide titration of statin therapy.
The RCTs showing a benefit in CVD outcomes with statin use have compared fixed-dose statin therapy with placebo, or high- versus low-dose statin therapy. There are no RCT data showing a significant benefit of particular lipid targets on CVD outcomes. As a result, repeated measurement of lipid levels for patients already taking statins is not required.
Patients at equivalent levels of risk will have the same benefit regardless of pretreatment LDL levels.
There is evidence for secondary prevention that higher doses or higher potency statins reduce CVD more than lower doses or lower potency statins. Therefore, recommended dosing should be based on intensity (representing both potency in the type of statin and dose) of statin therapy.
Testing for baseline CK or ALT levels in healthy individuals before starting statin therapy is generally unnecessary (low-level evidence).
The evidence against testing baseline ALT or CK levels is poor, so routine monitoring of CK and ALT levels should be reserved for those patients who are symptomatic or who are at higher risk of an adverse event.
View our Quick Links section for a summary lipid algorithm from TOP (Toward Optimized Practice) and lipids guidelines.