title: Assessment of risk factors for earlier onset of sporadic Alzheimer's disease dementia.
abstract: BACKGROUND
  Pharmacological treatment has mild effects for patients with Alzheimer's disease dementia (AD); therefore, the search for modifiable risk factors is an important challenge. Though risk factors for AD are widely recognized, elements that influence the time of dementia onset have not been comprehensively reported. We aimed to investigate which risk factors might be related to the age of onset of AD in a sample of patients with highly variable educational levels, taking into account the Framingham risk scoring as the sole measure of vascular risk.
  
  
  METHODS
  We included 209 consecutive late-onset AD patients to find out which factors among educational levels, coronary heart disease risk estimated by way of Framingham risk scores, history of head trauma or depression, surgical procedures under general anesthesia, family history of neurodegenerative diseases, gender, marital status and APOE haplotypes might be related to the age of dementia onset in this sample of patients with low mean schooling.
  
  
  RESULTS
  Mean age of AD onset was 73.38±6.5 years old, unaffected by schooling or family history of neurodegenerative diseases. Patients who were APOE-ε4 carriers, married, or with history of depression, had earlier onset of AD, particularly when they were women. Coronary heart disease risk was marginally significant for later onset of AD.
  
  
  CONCLUSIONS
  APOE haplotypes, marital status and history of depression were the most important factors to influence the age of AD onset in this sample. While midlife cerebrovascular risk factors may increase incidence of AD, they may lead to later dementia onset when present in late life.
authors.affiliation: Department of Neurology and Neurosurgery, Escola Paulista de Medicina, Federal University of São Paulo-UNIFESP, Brazil.
authors.forename: Fabricio Ferreira
authors.initials: FF
authors.lastname: de Oliveira
authors.forename: Paulo Henrique Ferreira
authors.initials: PH
authors.lastname: Bertolucci
authors.forename: Elizabeth Suchi
authors.initials: ES
authors.lastname: Chen
authors.forename: Marilia Cardoso
authors.initials: MC
authors.lastname: Smith
mesh_terms: D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000235:genetics*; D053327:Apolipoprotein E4 / Q000235:genetics*; D003704:Dementia / Q000453:epidemiology / Q000235:genetics; D004522:Educational Status; D005260:Female; D006239:Haplotypes; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D053327:Apolipoprotein E4