METABOLIC SYNDROME AND RISK FOR INCIDENT ALZHEIMER'S DISEASE OR VASCULAR DEMENTIA: THE THREE – CITY STUDY

Abstract

Objective Associations between metabolic syndrome (MetS), and its individual components, with risk of incident dementia, and its different subtypes, are inconsistent.

Research design and methods The 7087 community-dwelling subjects aged 65 yr and over were recruited from the French Three-City (3C) cohort. Hazard ratios of incident dementia over four years – and its subtypes (vascular dementia and Alzheimer's disease (AD)) - associated with MetS (defined according to the NCEP ATP III Criteria) - and its individual components (hypertension, large waist circumference, high triglycerides, low HDL-cholesterol, elevated fasting glycemia) - were estimated in separate Cox proportional hazard models.

Results MetS was present in 15.8% of the study participants. The presence of MetS increased the risk of incident vascular dementia but not AD over four years independently of socio-demographic characteristics and Apolipoprotein E ε4 allele. High triglycerides level was the only component of MetS that was significantly associated with the incidence of all-cause dementia (HR = 1.45 [1.05 – 2.00]; p = 0.02) and vascular dementia (HR = 2.27 [1.16 – 4.42]; p = 0.02), even after adjustment on Apolipoprotein E genotype. Diabetes, but not impaired fasting glycemia, was significantly associated with all-cause dementia (HR = 1.58 [1.05 – 2.38]; p = 0.03) and vascular dementia (HR = 2.53 [1.15 – 5.66]; p = 0.03).

Conclusions The observed relation between high triglycerides, diabetes and vascular dementia emphasizes the need for detection and treatment of vascular risk factors in older persons in order to prevent the likelihood of clinical dementia.