Risk factors for cognitive disorders in the elderly: A review

Summary per reviews the current literature on the main risk factors, which are involved in Alzheimerʹs disease (AD) and cognitive disorders in the elderly. The pathogenesis of secondary dementias is discussed, with particular reference to vascular risk factors and slow virus infections. The involvement of genetic factors is analyzed in depth, focusing on studies of molecular biology; these studies have shown missense mutations located on chromosomes 21, 1 and 14, responsible mainly of early onset familial Alzheimerʹs disease (EOFAD). The collected data suggest a common pathogenetic pathway for EOFAD gene defects, revolving around an overproduction of amyloid beta peptide or of its more amyloidogenic version Aβ1-42. Moreover, the association between the ɛ4 allele of the apolipoprotein E and the familial or sporadic forms of AD is discussed. Finally, epidemiological data on the role of age, education, occupation, life habits and environment are reported.