Impact of Depressive Symptoms on Conversion from Mild Cognitive Impairment Subtypes to Alzheimer's Disease: A Community-Based Longitudinal Study.

BACKGROUND: While longitudinal studies have investigated the relationships between mild cognitive impairment (MCI) subtypes and dementia subtypes, the results have been contradictory. In addition, some research shows that depression accompanied by MCI might increase the risk of Alzheimer's disease (AD). OBJECTIVE: The aim of this study is to longitudinally investigate the relationships between MCI subtypes and dementia subtypes, with special attention to the effect of comorbid depressive symptoms in a Japanese rural community. METHODS: Non-demented participants (n = 802) completed a baseline and follow-up study. Outcomes were conversion to dementia especially AD, MCI, or no conversion. A complementary log-log analysis was conducted to investigate the risk of dementia and AD in amnestic MCI (aMCI) compared to nonamnestic MCI (naMCI) groups. The impact of depressive symptoms on the transition from MCI to AD and from cognitively normal to MCI or AD was also analyzed. RESULTS: The risk of developing dementia, in particular AD, for the aMCI group was significantly higher than that for the naMCI group. In the aMCI group, the presence of depressive symptoms increased the risk of developing AD, but depressive symptoms in the naMCI group did not. In the cognitively normal group, the presence of depressive symptoms increased the risk of aMCI but not naMCI or AD. CONCLUSION: MCI subtyping could be useful in finding a prodrome for dementia and in particular for AD. The differing impacts of depressive symptoms on the development of AD suggest that the relationship between depressive symptoms and cognitive impairment could differ in aMCI and naMCI patients.

A combination of supplements may reduce the risk of Alzheimer's disease in elderly Japanese with normal cognition.

A number of studies have examined the effect of a single supplement against Alzheimer's disease (AD) with conflicting results. Taking into account the complex and multifactorial nature of AD pathogenesis, multiple supplements may be more effective. Physical activity is another prospect against AD. An open-label intervention study was conducted to explore a potential protective effect of multiple supplements and physical activity. Their interaction was also examined. Participants were community-dwelling volunteers aged 65 or older as of May 2001 in a rural area of Japan. Among 918 cognitively normal participants included in the analyses, 171 took capsules daily for three years that contained n-3 polyunsaturated fatty acid, Ginkgo biloba leaf dry extracts, and lycopene. Two hundred and forty one participants joined the two-year exercise intervention that included a community center-based and a home-based exercise program. One-hundred and forty eight participated in both interventions. A standardized neuropsychological battery was administered at baseline in 2001, the first follow-up in 2004-2005, and the second in 2008-2009. The primary outcome was AD diagnosis at follow-ups. A complementary log-log model was used for survival analysis. A total of 76 participants were diagnosed with AD during follow-up periods. Higher adherence to supplementation intervention was associated with lower AD incidence in both unadjusted and adjusted models. Exercise intervention was also associated with lower AD incidence in the unadjusted model, but not in the adjusted model. We hypothesized that the combination of supplements acted in a complementary and synergistic fashion to bring significant effects against AD occurrence.

Brachial and lumbar plexuses in chronic inflammatory demyelinating polyradiculoneuropathy: MRI assessment including apparent diffusion coefficient.

INTRODUCTION: Our purpose was to clarify the magnetic resonance (MR) imaging characteristics of the brachial and lumbar plexuses in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) using various kinds of sequences, including diffusion-weighted images (DWI). METHODS: We evaluated the MR imaging findings for lumbar and/or brachial nerve plexuses in 13 CIDP patients and 11 normal volunteers. The nerve swelling was evaluated in comparison with normal controls by coronal short tau inversion recovery (STIR), and signal abnormalities were evaluated by coronal STIR, T1-weighted images, and DWIs. The degrees of contrast enhancement and apparent diffusion coefficient (ADC) values of the plexus were also assessed. RESULTS: In the patient group, diffuse enlargement and abnormally high signals were detected in 16 out of 24 plexuses (66.7%) on STIR, a slightly high signal was detected in 12 of 24 plexuses (50%) on T1-weighted images, and a high-intensity signal was detected in 10 of 18 plexuses (55.6%) on DWIs with high ADC values. Contrast enhancement of the plexuses was revealed in 6 of 19 plexuses (31.6%) and was mild in all cases. There were statistically significant differences between the ADC values of patients with either swelling or abnormal signals and those of both normal volunteers and patients without neither swelling nor abnormal signals. There were no relationships between MR imaging and any clinical findings. CONCLUSION: STIR is sufficient to assist clinicians in diagnosing CIDP. T1-weighted images and DWIs seemed useful for speculating about the pathological changes in swollen plexuses in CIDP patients.

Degeneration of dementia with Lewy bodies measured by diffusion tensor imaging.

Dementia with Lewy bodies (DLB) is the second most common form of dementia. It is thought to involve impairment of the visual association area. In this study, we applied diffusion tensor imaging (DTI) to examine the microstructural interruption of visual association areas in patients with DLB. The DTI metrics of three visual association fibres - the inferior longitudinal fasciculus (ILF), visual pathway, and splenial fibres - were compared between 14 patients with DLB and 13 healthy subjects. The fractional anisotropy value of the ILF was significantly lower in patients with DLB than in healthy subjects. The difference in the mean diffusivity value of ILF was at trend level. The lambda(2),(3) of ILF were significantly lower in patients with DLB; however, there was no difference in lambda(1). DTI metrics of the visual pathway and splenial fibres showed no differences between the groups. Our results showed degeneration of the ILF, which is responsible for visuospatial cognition. ILF dysfunction may influence the clinical features in DLB.

[Biochemical and bacteriological investigation of six cases of purple urine bag syndrome (PUBS) in a geriatric ward for dementia].

AIM: Purple urine bag syndrome is a condition in which the urinary catheter bag turns purple. A tryptophan-indigo hypothesis has been proposed as the mechanism of PUBS, in which bacterial decomposition of tryptophan in gut associated with chronic constipation, bacterial overgrowth in the urinary tract and alkaline urine causes production of indigo and discoloration. We considered that further investigation of cases was needed. METHODS: We investigated 6 cases exhibiting PUBS (3 males and 3 females). RESULTS: All cases had chronic constipation. Oral ingestion was impossible in one case. PUBS disappeared after antibiotic treatment (3 cases) or spontaneously (one case). Alkaline urine and indicanuria were not found in all cases that showed the disappearance of PUBS. In bacterial culture of urine during the exhibition of PUBS, Enterococcus faecalis was isolated together with Morganella morganii (3 cases) and Pseudomonas aeruginosa (one case). Single infections by Klebsiella pneumoniae or Citrobacter species were also found. After disappearance of PUBS, infected bacterial species changed but no cases showed sterile urine. Urine and blood alpha-amino-n-butyric acid levels reduced after the disappearance of PUBS whereas tryptophan levels did not show related changes. In one case, blood protein concentration increased after the spontaneous disappearance of PUBS. Indicanuria and alkalization of urine from urinary catheter bag were more intense than of fresh urine. CONCLUSIONS: The present results generally support the 'Tryptophan-indigo hypothesis'. Furthermore, it was suggested that additional factors associated with the occurrence of PUBS are an environment that facilitates specific bacterial growth in a hospital as well as abnormal metabolism relating to alpha-amino-n-butyric acid and reduced protein synthesis in patients.