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Irwin Rosenberg

Publications and source records attributed to Irwin Rosenberg.

8 recordsLinked to original sources

Depression is associated with low plasma Abeta42 independently of cardiovascular disease in the homebound elderly.

BACKGROUND: Depression often precedes the onset of Alzheimer's disease (AD) before the appearance of cognitive symptoms. Plasma Amyloid-beta peptide 42 (Abeta42) declines before and soon after the onset of AD, yet the relationship between plasma Abeta42 and depression is unclear. METHODS: We used 515 homebound elders aged 60 and older in a population-based, cross-sectional study to investigate associations between plasma Abeta levels and depression with and without cardiovascular co-morbidities. Depression was evaluated by using the Center for Epidemiological Studies Depression (CES-D) scale. Plasma Abeta40 and Abeta42 were measured. RESULTS: The elderly with depression had lower plasma Abeta42 (median: 15.3 vs. 18.9, p = 0.008) than those without depression. The CES-D score was inversely associated with plasma Abeta42 (p = 0.001) in subjects with no cardiovascular disease (CVD); however, in the presence of CVD, this association did not exist. Low plasma Abeta42 (OR = 0.41, p = 0.007) and the presence of CVD (OR = 1.84, p = 0.005) were independently associated with depression after adjusting for the confounders of age, stroke and apolipoprotein E4. CONCLUSIONS: Depressive symptoms are associated with low plasma Abeta42 independently of CVD. Prospective studies are needed to determine whether depression associated with low plasma Abeta42 is a separate depression subtype that could predict the onset of AD.

Age Factors↗

The Nutrition, Aging, and Memory in Elders (NAME) study: design and methods for a study of micronutrients and cognitive function in a homebound elderly population.

BACKGROUND: Micronutrient status can affect cognitive function in the elderly; however, there is much to learn about the precise effects. Understanding mediating factors by which micronutrient status affects cognitive function would contribute to elders' quality of life and their ability to remain in the home. OBJECTIVES: The Nutrition, Aging, and Memory in Elders (NAME) Study is designed to advance the current level of knowledge by investigating potential mediating factors by which micronutrient status contributes to cognitive impairment and central nervous system abnormalities in the elderly. NAME targets homebound elders because they are understudied and particularly at risk for poor nutritional status. METHODS: Subjects are community-based elders aged 60 and older, recruited through area Aging Services Access Points. The NAME core data include demographics; neuropsychological testing and activities of daily living measures; food frequency, health and behavioral questionnaires; anthropometrics; gene status; plasma micronutrients, homocysteine, and other blood determinants. A neurological examination, psychiatric examination, and brain MRI and volumetric measurements are obtained from a sub-sample. RESULTS: Preliminary data from first 300 subjects are reported. These data show that the NAME protocol is feasible and that the enrolled subjects are racially diverse, at-risk, and had similar basic demographics to the population from which they were drawn. CONCLUSION: The goal of the NAME study is to evaluate novel relationships between nutritional factors and cognitive impairment. These data may provide important information on potential new therapeutic strategies and supplementation standards for the elderly to maintain cognitive function and potentially reduce the public health costs of dementia.

Activities of Daily Living↗

Executive dysfunction in homebound older people with diabetes mellitus.

OBJECTIVES: To describe patterns of cognitive deficits and activities of daily living (ADLs) in older people with diabetes mellitus. DESIGN: Cross-sectional, population-based study. SETTING: Three homecare agency areas in Boston, Massachusetts. PARTICIPANTS: Two hundred ninety-one homebound people aged 60 and older; 40% with diabetes mellitus. MEASUREMENTS: Demographic data; evidence of diabetes mellitus and other diseases; Mini-Mental State Examination and tests of memory and executive function; ADLs. RESULTS: Executive and visuospatial functions were more impaired in individuals with diabetes mellitus than in those without, as assessed using Block Design (mean score+/-standard deviation 17.1+/-8.6 vs 20.5+/-9.6, P=.003) and Trails B (median seconds to accomplish the task: 255 vs 201, P=.03). For memory, word retention score was lower in those with diabetes mellitus than without (39.1+/-28.9 vs 48.0+/-29.7, P=.01), but the other memory tests did not show a difference between these two subgroups. More individuals with diabetes mellitus suffered from depressive symptoms than those without (55% vs 42%, P=.03). The ADL scores of those with diabetes mellitus were higher than those without. CONCLUSION: The pattern of cognitive deficits in people with diabetes mellitus suggests frontal-subcortical dysfunction, as seen in microvascular disease of the brain. The impairment in ADLs may be associated with this executive dysfunction, which cerebral microvascular disease in diabetes mellitus may cause.

Activities of Daily Living↗

Nutrition and aging: changes in the regulation of energy metabolism with aging.

Changes in energy regulation occur during normal aging and contribute to the common phenomenon of weight and fat losses late in life. This review synthesizes data on aging-related changes in energy intake and energy expenditure and on the regulation of energy intake and expenditure. The ability of older adults to accurately regulate energy intake is impaired, with a number of possible explanations including delayed rate of absorption of macronutrients secondary to reductions in taste and smell acuity and numerous hormonal and metabolic mediators of energy regulation that change with aging. There are also changes in patterns of dietary intake and a reduction in the variety of foods consumed in old age that are thought to further reduce energy intake. Additionally, all components of energy expenditure decrease with aging, in particular energy expenditure for physical activity and basal metabolic rate, and the ability of energy expenditure to increase or decrease to attenuate energy imbalance during overeating or undereating also decreases. Combined, these changes result in an increased susceptibility to energy imbalance (both positive and negative) in old age that is associated with deteriorations in health. Practical interventions for prevention of weight and fat fluctuations in old age are anticipated here based on emerging knowledge of the role of such factors as dietary variety, taste, and palatability in late-life energy regulation.

Aging↗

Homocysteine and cognitive function.

The prevention and treatment of age-related cognitive impairment and dementia is one of the greatest and most elusive challenges of our time. The prevalence of dementia increases exponentially with age, as does the prevalence of those with micronutrient deficiency. Several studies have shown that elevated homocysteine is correlated with cognitive decline and with cerebral atrophy and that it predicts the subsequent development of dementia in cognitively intact middle-aged and elderly individuals. If elevated homocysteine promotes cognitive dysfunction, then lowering homocysteine by means of B-vitamin supplementation may protect cognitive function by arresting or slowing the disease process.

Cognition↗

High homocysteine and low B vitamins predict cognitive decline in aging men: the Veterans Affairs Normative Aging Study.

BACKGROUND: Elevated homocysteine concentrations may contribute to cognitive impairment. Most elevations in homocysteine result from inadequate folate, vitamin B-12, or vitamin B-6 intake. It is not clear whether the observed associations between homocysteine and cognitive measures are causal or whether they are due to homocysteine, to independent actions of the B vitamins, or to both. OBJECTIVE: We aimed to assess the individual and independent effects of baseline plasma homocysteine, folate, vitamin B-12, and vitamin B-6 and of dietary B vitamin intakes on 3-y changes in cognitive measures in 321 aging men. DESIGN: Participants were from the Veterans Affairs Normative Aging Study. Cognitive function was assessed with the Mini-Mental State Examination and on the basis of measures of memory, verbal fluency, and constructional praxis, which were adapted from the revised Wechsler Adult Intelligence Scale and the Consortium to Establish a Registry for Alzheimer's Disease batteries at 2 time points. At baseline, dietary intakes were assessed with a food-frequency questionnaire, and blood was drawn for the measurement of B vitamins and homocysteine. RESULTS: Over a mean 3-y follow-up, declines in constructional praxis, measured by spatial copying, were significantly associated with plasma homocysteine, folate, and vitamins B-6 and B-12 and with the dietary intake of each vitamin. Folate (plasma and dietary) remained independently protective against a decline in spatial copying score after adjustment for other vitamins and for plasma homocysteine. Dietary folate was also protective against a decline in verbal fluency. A high homocysteine concentration was associated with a decline in recall memory. CONCLUSIONS: Low B vitamin and high homocysteine concentrations predict cognitive decline. Spatial copying measures appear to be most sensitive to these effects in a general population of aging men.

Aged↗

Enhancement of folates in plants through metabolic engineering.

Humans depend on plants as a major source of dietary folates. Inadequate dietary levels of the vitamin folate can lead to megaloblastic anemia, birth defects, impaired cognitive development, and increased risk of cardiovascular disease and cancer. The biofortification of folate levels in food crops is a target for metabolic engineering. Folates are synthesized de novo from pterins and para-amino benzoic acid, which are subsequently combined to form dihydropteroate, the direct precursor to dihydrofolate. We postulated that GTP cyclohydrolase-1, which catalyzes the first committed step in pterin biosynthesis, was a rate-limiting step in pterin synthesis in plants and, therefore, in folate synthesis. On this basis, we proposed that the expression of an unregulated bacterial GTP cyclohydrolase-1 in plants would increase pterin biosynthesis with a concomitant enhancement of folate levels. The folE gene encoding GTP cyclohydrolase-1 was cloned from Escherichia coli and introduced into Arabidopsis thaliana through plant transformation. The expression of bacterial GTP cyclohydrolase-1 in transgenic Arabidopsis resulted in a 1,250-fold and 2- to 4-fold enhancement of pterins and folates, respectively. These results helped to identify other potential factors regulating folate synthesis, suggesting ways to further enhance folate levels in food crops.

Arabidopsis↗

Homocysteine and B vitamins relate to brain volume and white-matter changes in geriatric patients with psychiatric disorders.

OBJECTIVE: There is a growing literature on the relationship between low serum B-vitamins, elevated homocysteine, and cognitive impairment; however, few studies have examined radiological markers of associated neuropathology in geropsychiatry inpatients. The authors examined the relationship of homocysteine, folate, and vitamin B12 with magnetic resonance imaging (MRI) markers of neuropathology. METHODS: In this archival study, authors reviewed the MRIs and medical records of 34 inpatients in a geriatric psychiatry unit. Patients were selected if folate, B12, and/or homocysteine levels had been assessed and if the appropriate clinical MRIs were performed (19 men; mean age, 75 years). Patients with schizophrenia or current substance dependence were excluded. The relationships between MRI volume measures, white-matter hyperintensity (WMH) grade, and serum concentrations of folate, B12, and homocysteine were analyzed, using age-adjusted Pearson correlations. RESULTS: Homocysteine was related to WMH grade, but not brain-volume measures. Folate was associated with hippocampus and amygdala, and negatively associated with WMH. B12 level was not statistically associated with any brain measure. CONCLUSIONS: Elevated homocysteine and low folate were associated with radiological markers of neuropathology. Since no patient had clinically deficient folate, it may be important to rethink what defines functionally significant micronutrient deficiency and explore what this means in different age- and health-status groups. Larger samples will be needed to assess interactions between homocysteine, micronutrients, and other neuropathology risk factors.

Adult↗