Elevated levels of low-density lipoprotein cholesterol (LDL-C) in people between the ages of 70 and 100 years were found to be associated with a higher absolute risk for myocardial infarction (MI) and atherosclerotic cardiovascular disease, according to a study published in the Lancet.
This was a systematic and meta-analysis in which data from the Copenhagen General Population Study (CGPS) of 91,131 people between the ages of 20 and 100 years who did not have atherosclerotic cardiovascular disease or diabetes at baseline and were not taking statin drugs were reviewed.
Standard hospital assays were used to measure total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides, and direct LDL-C. The absolute event rates for MI and atherosclerotic cardiovascular disease were calculated, and the investigators also estimated the number needed to treat (NNT) in 5 years to prevent 1 of those event.
A total of 1515 people in the CGPS cohort had a first MI, and 3389 had atherosclerotic cardiovascular disease during the follow-up period (mean, 7.7 years). The risk for MI per 1·0 mmol/L increase in LDL-C increased for the overall cohort (hazard ratio [HR], 1.34; 95% CI, 1.27–1.41), and was further increased in people ages 70 to 100 years.
The risk for atherosclerotic cardiovascular disease increased per 1.0 mmol/L increase in LDL-C in the overall population (HR, 1.16; 95% CI, 1.12–1.21) and in all age groups, with a greater increase in the 70 to 100 years age group. Additionally, the risk for MI increased with LDL-C levels ≥5.0 mmol/L vs <3.0 mmol/L in people ages 80 to 100 years (HR, 2.99; 95% CI, 1.71–5.23) and in people ages 70 to 79 years (HR, 1.82; 95% CI, 1.20–2.77).
The number of MI and atherosclerotic cardiovascular disease events per 1000 person-years for every 1.0 mmol/L increase in LDL was higher among people ages 70 to 100 years. The estimated NNT in 5 years to prevent 1 MI or atherosclerotic cardiovascular disease event was lowest for people ages 70 to 100 years, among those on a moderate-intensity statin regimen.
Limitations of this study include the fact that the cohort solely comprised individuals of white European descent, as well as the reliance on modelling analyses for the estimation of NNT in 5 years.
“Our data are important for preventive strategies aimed at reducing the burden of MI and atherosclerotic cardiovascular disease in the growing population ages 70 to 100 years,” concluded the study authors.
Mortensen MB, Nordestgaard BG. Elevated LDL cholesterol and increased risk of myocardial infarction and atherosclerotic cardiovascular disease in individuals aged 70–100 years: a contemporary primary prevention cohort. Lancet. Published online November 10, 2020. doi:10.1016/S0140-6736(20)32233-9