INTRODUCTION: In animal models, refined carbohydrates (RF) worsen Alzheimer's disease (AD). However, the long-term effects of high RF intake on the risk of dementia and AD are poorly described in epidemiological studies. Moreover, the interaction between RF and apolipoprotein E ε4 allele (APOE-ε4) is unknown. Our study investigated whether RF-rich diets are associated with the risk of dementia and AD. METHODS: The glycemic load was quantified in 2,777 elderly participants from the French Three-City Study to estimate RF intake. Then, the association between glycemic load and risk of dementia and AD, and the interaction with APOE-ε4 over a 12-year period were assessed using proportional hazards models. 1 1 2 RESULTS: After adjustment for potential confounders, high afternoon-snack glycemic load was associated with increased dementia and AD risk in APOE-ε4 carriers (HR = 1.27 [1.03-1.56]). DISCUSSION: This study highlights that RF-rich diets are a risk factor for dementia and AD in APOE-ε4 carriers.

Statins are a class of widely prescribed drugs used to reduce low-density lipoprotein cholesterol (LDL-C) and important to prevent cardiovascular diseases (CVD). Most statin users are older adults with CVD, who are also at high risk of cognitive decline. It has been suggested that statins can alter cognitive performance, although their positive or negative effects are still debated. With more than 200 million people on statin therapy worldwide, it is crucial to understand the reasons behind discrepancies in the results of these studies. Here, we review the effects of statins on cognitive function and their association with different etiologies of dementia, and particularly, Alzheimer’s disease (AD). First, we summarized the main individual and statin-related factors that could modify the cognitive effects of statins. Second, we proposed the underlying mechanisms for the protective and adverse effects of statins on cognitive performance. Finally, we discussed potential causes of discrepancies between studies and suggested approaches to improve future studies assessing the impact of statins on dementia risk and cognitive function.