Low levels of low-density lipoprotein cholesterol and cognitive decline

The relationship between low levels of serum low-density lipoprotein cholesterol(LDL-C)and subsequent cognitive decline remains unclear.The present study aimed to evaluate the longitudinal association between low LDL-C levels and cognition decline in the context of the current aggressive guideline-recommended targets(LDL-C levels less than 55 mg/dL for individuals at very high risk of cardiovascular events,and less than 70 mg/dL for high risk individuals).Data from wave 13(2016)to wave 14(2018)of the Health and Retirement Study(HRS)were utilized.LDL-C concentrations measured at wave 13 were categorized into 5 levels,reflecting currently recommended values for lipid lowering treatment.Of 7129 included participants(mean age:69.0±9.9 years,60.3%female),we found that compared to participants with LDL-C levels of 70.0-99.9 mg/dL,those with LDL-C levels of<55 mg/dL had significantly slower 2-year decline rates in global cognitive function(0.244 point/year;95%confidence interval(CI):0.065-0.422;P=0.008),working memory(0.068 point/year;95%CI:0.004-0.133;P=0.038),and borderline significantly in episodic memory(0.155 point/year;95%CI:-0.004-0.315;P=0.057).Similarly,significantly slower decline rates were observed in those with LDL-C levels of 55.0-69.9 mg/dL.The present study demonstrated that compared with LDL-C levels 70.0-99.9 mg/dL,low LDL-C levels(<70 mg/dL,especially<55 mg/dL)were associated with significantly slower cognitive decline in population-based setting.Future randomized controlled trials are warranted to ascertain the safety and benefit of current aggressive guideline-recommended targets on cognitive function.