Is Targeting LDL-C Levels Below 70 mg/dL Beneficial for Cardiovascular and Overall Health? A Critical Examination of the Evidence.

Over the past two decades, cardiovascular disease (CVD) prevention guidelines have progressively lowered LDL-C targets to <70 mg/dL for high-risk individuals based on the assumption of a linear relationship between LDL-C levels and CVD risk. However, the available evidence challenges this premise. Multiple studies demonstrate a weak or inconsistent association between LDL-C levels and atherosclerosis progression at the individual patient-level. Systematic reviews supporting the linearity assumption have notable limitations, including extrapolation beyond observed LDL-C ranges and potential ecological fallacy, as meta-regression analyses rely on study-level data, while patient-level data within the same trials often show no association between LDL-C reduction and CVD outcomes. Moreover, randomized controlled trials explicitly designed to assess LDL-C targets have yielded inconclusive and biased results. LDL-C itself is a heterogeneous marker, with particle size and composition influencing its atherogenicity. The cardiovascular benefits of lipid-lowering therapies may arise in part from pleiotropic effects unrelated to LDL-C lowering. Additionally, several studies indicate that higher LDL-C levels are paradoxically associated with longevity in elderly populations that is equal to or even greater than that of the general population. Collectively, this body of evidence raises questions about the validity of current LDL-C targets < 70 mg/dL in high-risk patients.