Mehlig K, et al. - In the present study, researchers examined the prospective relationship between fasting serum insulin and dementia, taking into account the incidence of diabetes mellitus in a representative population of women followed over 34 years. For this investigation, they obtained fasting values for serum insulin and blood glucose in 1,212 nondiabetic women 38 to 60 years of age at the 1968 baseline. A nonlinear relationship was found in this female population, with high risk at low insulin values not ascribed to preclinical dementia or impaired insulin secretion. This investigation provided epidemiologic evidence for a new pathway to dementia that was described by low fasting serum insulin and varies from the metabolic pathway by means of hyperinsulinemia or diabetes mellitus.