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Do you need a supplement of docosahexaenoic acid or an n-3 long-chain polyunsaturated fatty acid?

Am J Clin Nutr. 2010 Mar 3;

Authors: Heird WC

PMID: 20200255 [PubMed - as supplied by publisher]

Zinc bioavailability and homeostasis.

Am J Clin Nutr. 2010 Mar 3;

Authors: Hambidge KM, Miller LV, Westcott JE, Sheng X, Krebs NF

Zinc has earned recognition recently as a micronutrient of outstanding and diverse biological, clinical, and global public health importance. Regulation of absorption by zinc transporters in the enterocyte, together with saturation kinetics of the absorption process into and across the enterocyte, are the principal means by which whole-body zinc homeostasis is maintained. Several physiologic factors, most notably the quantity of zinc ingested, determine the quantity of zinc absorbed and the efficiency of absorption. Other factors are age and the time over which zinc is ingested. Zinc from supplements has not been shown to be absorbed differently from that taken with meals that lack inhibitors of zinc absorption. The principal dietary factor known to impair zinc bioavailability is inositol hexa- (and penta-) phosphate or phytate. Modeling of zinc absorption as a function of dietary zinc and phytate accounts for >80% of the variability in the quantity of zinc absorbed. Fitting the model to new data has resulted in continual improvement in parameter estimates, which currently indicate a maximal absorption in adults of approximately 6 mg Zn/d and that the average estimated dietary requirement doubles with 1000 mg dietary phytate/d. Intestinal excretion of endogenous zinc is regulated in response to recent absorption and to zinc status. The quantitative relation of intestinal excretion of endogenous zinc to zinc absorption is currently considered to be of major importance in the determination of zinc requirements. The effects of phytate on intestinal losses of endogenous zinc merit further investigation but are probably not of the same magnitude as its inhibitory effects on absorption of exogenous zinc.

PMID: 20200254 [PubMed - as supplied by publisher]

We present the case of a 39-year-old patient with frontotemporal dementia. This case depicts the complexities in the process leading to the diagnosis, treatment, and placement of young patients presenting with severe psychiatric symptoms as the first signs of an underlying neurological disease. Obstacles in the health care system and residential placement process that hinder the optimal and timely care of such difficult cases are discussed. Practical solutions are offered that center upon better awareness and education and the provision of additional resources. These interventions are likely to provide a positive return on investment for the medical system and could be used as strong levers for new health policies relevant to younger patients with neurological illness.

As life expectancy continues to increase, Alzheimer’s disease (AD) has become much more prevalent and as yet there is no cure. This has given rise to the situation Tithonus faced in Greek mythology of living longer but not staying young. In this article, the authors explore this phenomenon while reviewing some notable people and AD.

We explored the association of Alzheimer’s disease (AD) Assessment Scale (ADAS-Cog) item scores with AD severity using cross-sectional and longitudinal data from the same study. Post hoc analyses were performed using placebo data from a 12-month trial of patients with mild-to-moderate AD (N = 281 randomized, N = 209 completed). Baseline distributions of ADAS-Cog item scores by Mini-Mental State Examination (MMSE) score and Clinical Dementia Rating (CDR) sum of boxes score (measures of dementia severity) were estimated using local and nonparametric regressions. Mixed-effect models were used to characterize ADAS-Cog item score changes over time by dementia severity (MMSE: mild = 21-26, moderate = 14-20; global CDR: mild = 0.5-1, moderate = 2). In the cross-sectional analysis of baseline ADAS-Cog item scores, orientation was the most sensitive item to differentiate patients across levels of cognitive impairment. Several items showed a ceiling effect, particularly in milder AD. In the longitudinal analysis of change scores over 12 months, orientation was the only item with noticeable decline (8%-10%) in mild AD. Most items showed modest declines (5%-20%) in moderate AD.

Primary Progressive Aphasia (PPA) is a neurodegenerative disorder initially presenting with progressive language imapirment. This article provides a clinically oriented review of PPA. Different clinical presentations and imaging findings of 3 subtypes, agrammatic, semantic and logopenic, are presented. Underlying neuropathology, medical and social management aspects of these patients are reviewed.

Objective: There are no Food and Drug Administration (FDA)-approved medications indicated for the treatment of frontotemporal dementia (FTD). We sought to determine the most commonly used drugs used to treat behavioral variant FTD (bvFTD) in specialized dementia clinics. Methods: Medication and demographic data from the Alzheimer’s Disease Research Centers of California (ARCC) and a multicenter FTD natural history study (NHS) data set were compared in bvFTD and Alzheimer’s disease (AD), and effects of demographic variables were assessed using logistic regression. Results: Overall, the percentage of patients taking one or more FDA-approved AD or psychiatric medications was similar in bvFTD and AD; however, after controlling for demographic variables, acetylcholinesterase inhibitor (AChI) use was less common in bvFTD, whereas memantine use remained similar in the 2 groups. Conclusions: Despite lack of evidence for efficacy, the use of AChIs and memantine is common in bvFTD. Clinical trials should be pursued to determine the optimal therapeutic interventions for bvFTD.

Background/rationale: Various interventions are available to manage verbal agitation (VA), but our understanding regarding their acceptability is limited. The purpose of this study is to compare the acceptability of 3 interventions from the point of view of elderly individuals: direct interaction (DI), differential reinforcement of incompatible behaviors (DRI), and risperidone (RIS). Methods: Participants (N = 69) evaluated the acceptability of each treatment according to the description of a fictional person who demonstrated aggressive or nonaggressive VA. Results: There is an interaction between the type of intervention and the severity of VA. For nonaggressive VA, DI is the most acceptable intervention followed by DRI and RIS. For aggressive VA, DI and DRI are more acceptable than RIS, but there is not a significant difference between them. The acceptability of each intervention is not associated with the participants’ characteristics. Conclusion: The results of this study highlight the acceptability of DI for managing VA.

Disease-specific assessments are not currently available for patients with Parkinson’s disease dementia (PDD). This study evaluated the criterion-related validity and test—retest reliability of the Alzheimer’s Disease Assessment scale cognitive subscale (ADAS-cog) in terms of sensitivity for differentiation between mild and moderate severity impairment in PDD. Six other dementia rating scales and cognitive tests were also examined. A total of 113 patients with PDD or Alzheimer disease were recruited into this 4-week, multicenter study, segregated into 2 severity groups based on Mini-Mental State Examination (MMSE) score. Mean ADAS-cog scores showed a statistically significant separation between mild and moderate severity patients in both dementias (P < .001). For the ADAS-cog, test—retest Spearman correlation coefficients were significant for each dementia type and severity. This study demonstrated the criterion-related validity and test—retest reliability for ADAS-cog in patients with PDD and strong correlations with MMSE. This supports the validity of previous results obtained with these measures in studies of patients with PDD.