Studies of LDL levels, therapies support treatment of those older than age 70

Low-density lipoprotein (LDL) cholesterol levels and use of lipid-lowering therapies were significantly associated with myocardial infarction and cardiovascular disease in individuals ages 70 to 100 years, according to two recent studies.

The Copenhagen General Population Study examined patients ages 20 to 100 years who did not have atherosclerotic cardiovascular disease or diabetes at baseline and who were not taking statins. Researchers enrolled 91,131 individuals from November 2003 through February 2015, with a mean of 7.7 years of follow-up. Of these patients, 1,515 had a first myocardial infarction and 3,389 developed atherosclerotic cardiovascular disease. Results were published by The Lancet on Nov. 10.

The hazard ratio (HR) of myocardial infarction per 1 mmol/L increase in LDL cholesterol was 1.34 (95% CI, 1.27 to 1.41) for the overall population. The association was found in each age group but was most significant in those ages 70 to 100 years. The same was true for atherosclerotic cardiovascular disease (HR, 1.16; 95% CI, 1.12 to 1.21). Risk for myocardial infarction was also increased with a 5 mmol/L or higher LDL cholesterol level versus less than 3 mmol/L in patients ages 80 to 100 years (HR, 2.99; 95% CI, 1.71 to 5.23) and ages 70 to 79 years (HR, 1.82; 95% CI, 1.20 to 2.77).

The number needed to treat with a moderate-intensity statin for five years to prevent one myocardial infarction or atherosclerotic cardiovascular disease event was lowest for those ages 70 to 100 years, the authors calculated. “Our data are important for preventive strategies aimed at reducing the burden of myocardial infarction and atherosclerotic cardiovascular disease in the growing population aged 70 to 100 years,” they wrote.

A simultaneously published systematic review and meta-analysis concluded that lipid lowering was as effective in reducing cardiovascular events in patients ages 75 years and older as in patients younger than age 75 years.

It included 24 trials from the Cholesterol Treatment Trialists' Collaboration meta-analysis, plus five additional individual trials. Of 244,090 patients from the trials, 8.8% were at least 75 years old, and among this group, 54.7% were from statin trials, 28.9% were from ezetimibe trials, and 16.4% were from PCSK9 inhibitor trials. Lowering LDL cholesterol levels significantly reduced the risk of major vascular events in these older patients (risk ratio [RR] per 1 mmol/L reduction in LDL cholesterol, 0.74; 95% CI, 0.61 to 0.89; P=0.0019).

Among older patients, the benefits of statin and nonstatin treatments were similar. The benefit of LDL cholesterol lowering in older patients was observed for each component of the composite outcome, including cardiovascular death (RR, 0.85; 95% CI, 0.74 to 0.98), myocardial infarction (RR, 0.80; 95% CI, 0.71 to 0.90), stroke (RR, 0.73; 95% CI, 0.61 to 0.87), and coronary revascularization (RR, 0.80; 95% CI, 0.66 to 0.96). “These results should strengthen guideline recommendations for the use of lipid-lowering therapies, including non-statin treatment, in older patients,” the paper stated.

An editorial accompanying both studies noted that the results should remind clinicians of the benefits of lipid lowering in both younger and older patients. “These findings support the concept of the cumulative burden of LDL cholesterol over one's lifetime and the progressive increase in risk for atherosclerotic cardiovascular disease, including myocardial infarction, with age,” it said.