Evaluation and Treatment of Dyslipidemia in the Elderly

The definition of elderly is arbitrary. In this chapter we will define elderly as greater than 75 years of age because both the US and European lipids guidelines use this age to differentiate therapy recommendations. Atherosclerotic cardiovascular disease (ASCVD) is a major cause of morbidity and mortality in the elderly. Age is a key risk factor for ASCVD and with identical risk factors the 10-year risk of an ASCVD event markedly increases with age. In fact, an older individual with excellent risk factors can still have a high risk for having an ASCVD event. ASCVD begins early in life and progresses until it leads to clinical events later in life. The age that one develops clinical manifestations of ASCVD is dependent on the severity of individual risk factors, the number of risk factors, and the duration of exposure to the risk factors. Elderly individuals have a long exposure to risk factors so even when the risk factors are relatively modest the cumulative effects can be sufficient to result in clinical ASCVD events. This explains why age is such a key variable in determining the risk of developing an ASCVD event. Cardiovascular outcome studies have demonstrated that lowering LDL-C levels with statins, ezetimibe, or PCSK 9 monoclonal antibodies will reduce ASCVD events in elderly patients with pre-existing cardiovascular disease (secondary prevention). In elderly patients without cardiovascular disease (primary prevention) the available data does not definitively demonstrate a decrease in ASCVD events with statin or ezetimibe therapy but is suggestive of a benefit (note there are no primary prevention trials with PCSK9 inhibitors). Additional data is required to determine if bempedoic acid and icosapent ethyl reduce ASCVD events in patients ≥ 75 years of age. Studies are currently underway to provide definitive information on whether statin therapy is beneficial as primary prevention in the elderly. In deciding whether to treat an elderly patient with lipid lowering drugs one needs to consider the following factors; the higher the LDL-C level the greater the benefit of lowering LDL-C, the greater the decrease in LDL-C the greater the benefit, the higher the absolute risk of ASCVD the greater the benefit of lowering LDL-C, life expectancy, competing non-cardiovascular disorders, risk of drug side effects, potential for drug interactions, and patient preferences. In elderly patients without pre-existing ASCVD one should estimate the patient’s risk of developing ASCVD events and in conjunction with the general principles described above discuss with the patient a treatment plan. Determining the coronary calcium score can be helpful if there is uncertainty regarding the appropriate decision. If the decision is to treat our goal in primary prevention patients is often an LDL-C < 100mg/dL but in high-risk patients our goal may be an LDL-C < 70mg/dL. Elderly patients with ASCVD should be treated with lipid lowering drugs to reduce ASCVD unless there are contraindications. At a minimum our goal is an LDL-C < 70mg/dL but we would prefer an LDL-C < 55mg/dL if they can be achieved with a statin + ezetimibe. In very high-risk patients our goal is an LDL-C < 55mg/dL and adding a PCSK9 inhibitor may be required to achieve these levels in some patients. Age per se should not be used to withhold therapy with lipid lowering drugs that can reduce the risk of ASCVD events. For complete coverage of all related areas of Endocrinology, please visit our on-line FREE web-text, WWW.ENDOTEXT.ORG.