Terracciano A, et al. - This study was conducted to ascertain whether increases in neuroticism, declines in conscientiousness, and changes in other personality traits occurred before the onset of mild cognitive impairment or dementia. The physicians identified no evidence for preclinical change in personality before the onset of mild cognitive impairment or dementia. These findings gave evidence against the reverse causality hypothesis and strengthened the evidence for personality traits as a risk factor for dementia.