Cardiovascular Risk and Blood Cholesterol in Old and Older Individuals

The approach of lowering blood cholesterol via statins and similar medications slows the onset of atherosclerosis and consequent stroke and heart attack, but it isn't anywhere near as large an effect as we would like. This class of therapy isn't a cure and cannot be a cure, in the sense of removing existing atherosclerotic lesions, the fatty deposits that catastrophically weaken and narrow blood vessels. The latest approaches, such as PCSK9 inhibitors, can in the extreme case lower blood cholesterol to as little as 10% of human normal, but the outcome is still only a minor reversal of existing lesions. Some benefit is better than no benefit, and blood cholesterol lowering medications have changed the shape of late life human mortality for the better, but this approach of lowered blood cholesterol is not the right direction for the future of this field.

An observational study suggests that among people who have not had a previous cardiovascular event, those aged 70 to 100 years may gain the most benefit from taking medications that lower cholesterol compared to younger age groups, in terms of the number of heart attacks and cardiovascular events that could potentially be prevented per person treated. The study, involving more than 90,000 people living in Copenhagen, Denmark, including 13,779 people aged between 70 and 100 years, concluded that people aged over 70 years had the highest incidence of heart attack and cardiovascular disease of any age group. Heart attacks per 1,000 people per year irrespective of LDL cholesterol levels: Age 80-100, 8.5; age 70-79, 5.2; age 60-69, 2.5; age 50-59, 1.8; age 20-49, 0.8 - i.e. in people aged 80-100 years, there were 8.5 heart attacks per 1,000 people each year.

The study also estimates that the number of older people who need to receive a moderate-intensity statin therapy to prevent one heart attack in five years is fewer than for younger age groups. One heart attack will be prevented for every 80 people aged 80 to 100 years treated. In people aged 50 to 59 years, 439 need to be treated to prevent one incidence of heart attack, the researchers estimate.

In a separate systematic review and meta-analysis, researchers show that cholesterol-lowering therapies are as effective at reducing cardiovascular events in people aged 75 years or older as they are in younger people. The study, which included data from more than 21,000 people aged 75 years or older from 29 randomised controlled trials, found that cholesterol-lowering medications reduced the relative risk of major vascular events in older patients by 26% per 1mmol/L reduction in LDL cholesterol, which is comparable to the risk reduction in patients younger than 75 years (15% per 1mmol/L reduction in LDL cholesterol).

Together, the findings strengthen evidence that cholesterol-lowering medications can benefit older adults, who have historically been underrepresented in clinical trials of these therapies, and could help reduce the burden of cardiovascular disease in an aging population.

Link: https://www.eurekalert.org/pub_releases/2020-11/tl-pss110920.php