The diabetic brain and cognition.

The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) is increasing with the aging of the population. Studies from the last several years have shown that people with diabetes have an increased risk for dementia and cognitive impairment. Therefore, the authors of this consensus review tried to elaborate on the role of diabetes, especially diabetes type 2 (T2DM) in both AD and VaD. Based on the clinical and experimental work of scientists from 18 countries participating in the International Congress on Vascular Disorders and on literature search using PUBMED, it can be concluded that T2DM is a risk factor for both, AD and VaD, based on a pathology of glucose utilization. This pathology is the consequence of a disturbance of insulin-related mechanisms leading to brain insulin resistance. Although the underlying pathological mechanisms for AD and VaD are different in many aspects, the contribution of T2DM and insulin resistant brain state (IRBS) to cerebrovascular disturbances in both disorders cannot be neglected. Therefore, early diagnosis of metabolic parameters including those relevant for T2DM is required. Moreover, it is possible that therapeutic options utilized today for diabetes treatment may also have an effect on the risk for dementia. T2DM/IRBS contribute to pathological processes in AD and VaD.

Group- and Home-Based Cognitive Intervention for Patients with Mild Cognitive Impairment: A Randomized Controlled Trial.

BACKGROUND: We examined the efficacy of group-based cognitive intervention (GCI) and home-based cognitive intervention (HCI) in amnestic mild cognitive impairment (aMCI) and intervention effects on serum brain-derived neurotrophic factor (BDNF). METHODS: In this randomized and rater-blinded trial, 293 patients with aMCI from 18 nationwide hospitals were randomized: 96 to the GCI group, 98 to the HCI group and 99 to the control group. For 12 weeks, subjects receiving GCI participated twice per week in group sessions led by trained instructors, and those receiving HCI completed homework materials 5 days per week. They were assessed at baseline, postintervention (PI) and at the 6-month follow-up after the intervention. The primary endpoint was the change from baseline to PI in the modified Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog). RESULTS: In comparison to the controls (a 0.8-point decrease), the subjects receiving GCI (a 2.3-point decrease, p = 0.01) or HCI (a 2.5-point decrease, p = 0.02) showed significant improvements in the modified ADAS-Cog at PI, respectively. By the 6-month follow-up, those receiving GCI or HCI had better scores in the modified ADAS-Cog than the controls. The changes in BDNF levels significantly correlated with the changes in the modified ADAS-Cog in the GCI (r = -0.29, p = 0.02 at PI) and HCI (r = -0.27, p = 0.03 at 6-month follow-up) groups, respectively. CONCLUSIONS: The GCI and HCI resulted in cognitive improvements in aMCI. An enhanced brain plasticity may be a component of the mechanism underpinning the cognitive improvements associated with the cognitive interventions.

Response to rivastigmine transdermal patch or memantine plus rivastigmine patch is affected by apolipoprotein E genotype in Alzheimer patients.

BACKGROUND/AIMS: The apolipoprotein E (APOE) genotype in response to pharmacological treatments in patients with Alzheimer's disease (AD) remains a matter of controversy. This analysis investigated the effect of the APOE genotype on the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine patch in patients with mild to moderate AD. METHODS: Two hundred and six (n = 206) patients with probable AD and Mini-Mental State Examination (MMSE) scores of 10-20 were randomized to rivastigmine patch monotherapy or memantine plus rivastigmine patch for 24 weeks. Of the 206 patients with probable AD, 146 patients who consented to genetic testing for APOE were included and assessed for this subgroup study. RESULTS: There were no significant differences on MMSE, NPI, ADAS-cog, ADCS-ADL, CDR-SB, NPI and FAB between rivastigmine patch monotherapy and memantine plus rivastigmine patch according to the APOE genotype. However, patients with moderately severe AD (MMSE ≤15) who were APOE ε4 carriers showed higher responder rates on ADCS-ADL with memantine plus rivastigmine patch compared to rivastigmine patch monotherapy. CONCLUSION: Moderately severe AD patients with the APOE ε4 allele may respond more favorably to memantine plus rivastigmine patch than ε4 noncarriers.

Validation analysis of the Attention Questionnaire Scale.

Screening tests that briefly measure early signs of cognitive dysfunction in Alzheimer's disease (AD) are lacking. We devised a new scale focused on early detecting cognitive dysfunction: the Attention Questionnaire Scale (AQS). We prospectively studied the AQS in 268 subjects with varying degrees of cognitive dysfunction and compared it with the Mini-Mental Status Examination (MMSE), digit span test, trail making test part B, letter cancellation test, Instrumental ADL, Geriatric Depression Scale, and Clinical Dementia Rating Scale. The internal consistency was excellent with the AQS (Cronbach's α = 0.945). There were significant differences in the overall AQS scores across varying degree of cognitive dysfunction (26.80 ± 3.43 in normal elderly, 20.78 ± 4.83 in patients with mild cognitive impairment (MCI), 19.01 ± 4.49 in early AD, 16.00 ± 5.03 in mild AD, and 12.02 ± 6.28 in moderate AD), and subjects with the early stage of cognitive dysfunction could be further distinguished using the AQS than MMSE. The area under the receiver operating characteristic curve was estimated to be 0.93 (95% confidence interval 0.89-0.97) in screening for normal elderly versus patients with MCI or various stages of AD. The AQS provides greater screening ability for early stage cognitive dysfunction, used not only as a screening tool but also an appropriate simple questionnaire.