Type 2 diabetes and/or its treatment leads to less cognitive impairment in Alzheimer's disease patients

Sirio-Libanés Hospital, Department of Neurology, School of Medicine, University of Buenos Aires (UBA), Buenos Aires, Argentina.
Diabetes research and clinical practice (Impact Factor: 2.54). 06/2012; 98(1):68-74. DOI: 10.1016/j.diabres.2012.05.013
Source: PubMed


To evaluate the cognitive performance of a homogeneous population of Alzheimer's disease (AD), non-demented Type 2 Diabetes Mellitus (DIAB), demented with concomitant diseases (AD+DIAB) and healthy control subjects. AD is a progressive dementia disorder characterized clinically by impairment of memory, cognition and behavior. Recently, a major research interest in AD has been placed on early evaluation. Diabetes is one of the clinical conditions that represent the greatest risk of developing oxidative stress and dementia. Glucose overload, leading to the development of impaired-induced insulin secretion in DIAB and has been suggested to slow or deter AD pathogenesis.
The degree of cognitive impairment was determined on the Alzheimer Disease Assessment Scale-Cognitive (ADAS-Cog) and the Folstein's Mini Mental State Examination (MMSE); the severity of dementia was quantified applying the Clinical Dementia Rating (CDR) test; the Hamilton test was employed to evaluate depressive conditions; the final population studied was 101 subjects.
The cognitive deterioration is statistically significantly lower (p<0.05) in AD+DIAB patients as compared with AD patients.
In this longitudinal study the superimposed diabetic condition was associated with a lower rate of cognitive decline, while diabetic non-demented patients and controls present normal scores.

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    • "Patients with T2D have a 2-to 3-fold higher risk of developing AD [37]. Cognitive deterioration is more marked in patients with AD and T2D than AD alone [38]. Furthermore, in patients with diabetes, the mean onset of dementia is 2 years earlier and survival outcomes are reported to be generally poorer [39]. "
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