Statins for cardiovascular health: Latest guidelines, evidence

Evidence published in the journal The Lancet in 2010 shows that reducing low-density lipoprotein cholesterol by 1mmol/L with statins reduces the risks of ischaemic heart disease and stroke by 24{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} to 25{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809}.

Statins reduce the risk of cardiovascular disease by lowering the level of low-density lipoprotein (LDL) cholesterol in the blood. Too much LDL cholesterol can build up as “plaques” in your blood vessels and narrow their diameter. Over time this narrowing can block blood flow to certain organs. If blood flow to the heart is blocked, it can cause a heart attack, and if it occurs in the brain, it can cause an ischemic stroke.

Targeting the right patients with statins is key to gaining the most benefit. The U.S. Preventive Services Task Force (USPSTF) recently published its Recommendation Statement for Statin Use for the Primary Prevention of Cardiovascular Disease in Adults in the Journal of the American Medical Association (JAMA). The recommendations were both slightly more conservative but also very similar to existing recommendations by the American College of Cardiology (ACC) and the American Heart Association (AHA).

The new guidance was published following an evidence review that included 22 randomized clinical trials, including additional data from three randomized control trials not included in the last set of guidelines published in 2016. On the back of this, they have issued three main recommendations for clinicians dealing with patients.

They advised:

• Statin use would yield moderate benefit for those ages 40-75 with one or more factors that could increase the risk of cardiovascular disease, no history of cardiovascular disease, and an estimated 10-year cardiovascular event risk of 10{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} or greater.
• Those of the same age with the same risk factors with a 10-year cardiovascular event risk factor of 7.5{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} to 10{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} will have a small net benefit from taking statins.
• However, there was not enough evidence to determine whether it’s beneficial to initiate statin use in those older than 75.

Dr. Edo Paz, cardiologist and VP of Medical at K Health, told Medical News Today in an email:

“In these updated guidelines, the USPSTF recommends that clinicians assess a patient’s risk of having a cardiovascular event (like a heart attack or stroke) to decide which patients should be treated with statin therapy.

The ACC/AHA also gives additional guidance around the intensity of statin therapy, differentiating between moderate and high intensity options. Overall, the USPSTF guidelines are a bit simpler, as it is geared to all primary care doctors, rather than to cardiologists.”

In the same week, a model was presented at the European Society of Cardiology Congress 2022 which echoed the findings of the review, supporting the use of statins in patients over 40 with high cardiovascular disease risk.

The study created a model using data from 118,000 participants of the Cholesterol Treatment Trialists’ Collaboration and 500,000 individuals from the UK Biobank. It looked specifically at the difference between continuing statins for life, compared to stop taking them at 80, as there is little evidence of their value in people older than age 75.

Lead author Dr. Runguo Wu of the Queen Mary University of London said: “Our study suggests that people who start taking statins in their 50s but stop at 80 years of age instead of continuing lifelong will lose 73{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} of the QALY benefit if they are at relatively low cardiovascular risk and 36{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} if they are at high cardiovascular risk – since those at elevated risk start to benefit earlier.

“Women’s cardiovascular risk is generally lower than men’s. This means that for women, most of the lifelong benefit from statins occurs later in life, and stopping therapy prematurely is likely more detrimental than for men.”

Rather than suggest that statin treatment was potentially controversial, clinicians should focus on the areas where statin guidelines overlap, said Prof. Salim Virani, professor of Cardiology at Baylor College of Medicine, Houston, TX, and one of the authors of the ACC/AHA Primary Prevention Guideline from 2018.

In an editorial published by the JAMA in the same issue as the USPSTF Recommendation Statement, Prof. Virani outlined that the review of the data did not find “any significant harm associated with statin therapy,” and called the recommendations “sensible and practical.”

In an interview with MNT, he explained that the main difference between these guidelines and the 2018 ACC/AHA guidelines was over whether the cut-off for introducing statins was for people with a 7.5{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} 10-year risk of cardiovascular disease as is the case with the ACC/AHA guidelines, or 10{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} as is the case with the most recent guidelines from the US Preventive Services Task Force.

“Most of the patients whose 10-year risk is 10{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} or higher, well, they have to be treated based on both the guidelines,” said Prof. Virani. He added that further modeling of how many people these slight differences would affect was due to be published in the coming weeks.

Prof. Virani explained that individual risk factors needed to be considered by clinicians and patients when considering whether or not they needed to initiate statin treatment. While risk factors such as obesity and diabetes were considered in both sets of guidelines, the guidelines from USPSTF did not mention South East Asian ancestry or pre-eclampsia, or the risks for postmenopausal women for example.

“Last but not the least, the ACC/AHA guidelines have what we call these risk enhancers, which are factors that are not there when somebody is doing their tenure risk calculation but might be important for a patient, for example, a patient having family history of premature cardiovascular disease, those patients need to be treated early, and the ACC/AHA guidelines account for those factors as well, which is notion the US Preventive Services Task Force recommendations.”