Cholesterol and cardiovascular risk
It is known that high LDL-C and the risk of atherosclerotic cardiovascular disease (ASCVD) are correlated. There is also research showing that LDL-C x time increases the risk of ASCVD, and that for the same LDL-C x time, younger people have a higher risk (1).
(A) Event rates after the reference age of 40 years stratified by area under the curve (AUC) of low-density lipoprotein cholesterol (LDL-C) from ages 18 to 40 years. A larger AUC indicates a higher risk of onset events after age 40.
(B) Onset event rate after the reference age of 40 years, stratified by both AUC and temporal change (slope) of LDL-C from 18 to 40 years of age. The risk of incident events has been shown to depend on both the cumulative exposure to LDL-C (measured by AUC) with respect to age and the temporal progression of AUC accumulation (slope).
Domanski, M. J et.al. (2020). JACC, 76(13), 1507.
Effects of statin preparations
Statin preparations are mainly used when cholesterol is high. Statins inhibit the enzyme HMG-CoA reductase, which is necessary for the production of cholesterol in the liver, thereby reducing the production of new cholesterol by the liver. This allows the body to recover excess LDL cholesterol, resulting in lower LDL cholesterol levels in the blood. LDL cholesterol causes arteriosclerosis, so lowering it is effective in preventing ASCVD.
What happens if you stop taking statins?
Discontinuation of statins has been reported to increase the risk of cardiovascular events (2).
Figure 1. Cumulative incidence curves for major cardiovascular event outcomes in the primary prevention cohort.
Figure 2. Cumulative incidence curves for major cardiovascular event outcomes in the secondary prevention cohort.
Discontinuation of statins in patients at high risk of cardiovascular events should be carefully considered. In other words``I took cholesterol medication and it went down, so I stopped taking it.'' Regarding this, we must take into account past medical conditions and the fact that quitting statin preparations may increase cardiovascular risk.
On the other hand, it may be necessary to separately consider the scientific basis for discontinuing statins in the elderly. There are no guideline recommendations for discontinuing statins in older adults (3). If you are taking a lot of medicines, you probably don't have to think about preventive effects or quality of life.
Characteristics of young myocardial infarction
This study was based on Japanese registry data, and it has been reported that the proportion of dyslipidemia in young patients with myocardial infarction is higher than in elderly patients with myocardial infarction (4).
Prevalence of risk factors by age group
The prevalence of risk factor profiles in younger and older populations is shown. Overall trends show that younger people have a higher proportion of male patients and a lower prevalence of traditional coronary artery disease risk factors, such as hypertension, diabetes, and chronic kidney disease (CKD), but a higher prevalence of smoking and dyslipidemia.
Ando, H. et.al. (2022). JACC. Asia, 2(5), 574–585.
Summary
It is thought that the ASCVD preventive effect of statin preparations for high LDL-C is achieved by continuing to take them. As you get older, you need to carefully consider the risks, benefits, and cost-effectiveness, but from the perspective of preventing ASCVD, it is better to continue taking the drug as much as possible.
References
- Domanski, M. J., Tian, X., Wu, C. O., Reis, J. P., Dey, A. K., Gu, Y., Zhao, L., Bae, S., Liu, K., Hasan, A. A., Zimrin, D., Farkouh, M. E., Hong, C. C., Lloyd-Jones, D. M., & Fuster, V. (2020). Time course of LDL cholesterol exposure and cardiovascular disease event risk. Journal of the American College of Cardiology, 76(13), 1507–1516.
- Thompson, W., Morin, L., Jarbøl, D. E., Andersen, J. H., Ernst, M. T., Nielsen, J. B., Haastrup, P., Schmidt, M., & Pottegård, A. (2021). Statin discontinuation and cardiovascular events among older people in Denmark. JAMA Network Open, 4(12), e2136802.
- Thompson, W., Morin, L., Jarbøl, D. E., Andersen, J. H., Ernst, M. T., Nielsen, J. B., Haastrup, P., Schmidt, M., & Pottegård, A. (2021). Statin discontinuation and cardiovascular events among older people in Denmark. JAMA Network Open, 4(12), e2136802.
- Ando, H., Yamaji, K., Kohsaka, S., Ishii, H., Sakakura, K., Goto, R., Nakano, Y., Takashima, H., Ikari, Y., & Amano, T. (2022). Clinical presentation and in-hospital outcomes of acute myocardial infarction in young patients: Japanese nationwide registry. JACC. Asia, 2(5), 574–585.