Trajectories of lipid profile with cognitive function: 12-year follow-up of Guangzhou Biobank cohort study

Studies on the trajectories of lipid profile with cognitive decline are scarce and inconsistent. We examined this association and explored potential effect modification. Lipid profiles including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and total cholesterol (TC) were measured at baseline, first and second follow-ups, and classified into trajectory groups. Immediate, delayed memory recall and cognitive function were assessed by the immediate (IWRT) and delayed 10-word recall test (DWRT), and mini-mental state examination (MMSE), respectively, at baseline and follow-ups, and converted into standardized scores. Linear mixed-effect model was used. Results show that elevated HDL-C was associated with increasing annual change rates in DWRT and MMSE scores (β (95% confidence intervals) = 0.005 (-0.001 to 0.011) SD/year and 0.020 (0.014 to 0.027) SD/year, respectively), while LDL-C and TC were associated with a decrease in DWRT scores (-0.005 (-0.008 to -0.001) SD/year and - 0.009 (-0.011 to -0.006) SD/year, respectively). Moderate-increasing HDL-C, high-decreasing LDL-C or moderate-decreasing TC trajectories were associated with increases in DWRT, IWRT and MMSE scores. Stronger associations were identified for HDL-C with an increase in MMSE scores within the lower family income group and for LDL-C with a decrease in IWRT scores among individuals taking lipid-lowering drug. In conclusion, HDL-C was associated with improvements, while LDL-C and TC with decline in memory and cognitive function. Increasing HDL-C and decreasing LDL-C and TC trajectories predicted better memory and cognitive performance. The observed effect modifications highlight the importance of personalized approaches in lipid management to optimize cognitive outcomes.