Associations of vitamin B12 status with cognitive domain performance in cognitively healthy older adults

Abstract A common polymorphism (775G>C) in the vitamin B12 transport protein, transcobalamin II (TCII), has been identified in which proline replaces arginine at codon 259. We determined the influence of TCII genotype on indices of B12 status, including total serum B12, the amount of B12 bound to TCII (holoTCII), methylmalonic acid, and homocysteine, in 128 healthy older adults (ages 40-88 years). Mean total B12 and homocysteine concentrations were not significantly different among the 3 genotypes. Mean holoTCII concentration was significantly higher in those subjects homozygous for the proline form of TCII (PP) compared with those homozygous for the arginine form (RR) and heterozygotes (PR) (P ≤ .006). In addition, mean methylmalonic acid concentrations were significantly lower in the PP and PR groups compared with the RR group (P ≤ .02). The PP genotype may be more efficient in delivering B12 to tissues, resulting in enhanced B12 functional status. TCII genotype may thus influence susceptibility to B12 deficiency.

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Investigating the Effects of Spacing on Working Memory Training Outcome: A Randomized, Controlled, Multisite Trial in Older Adults

The Journals of Gerontology Series B ◽

10.1093/geronb/gbz090 ◽

2019 ◽

Vol 75 (6) ◽

pp. 1181-1192

Author(s):

Susanne M Jaeggi ◽

Martin Buschkuehl ◽

Chelsea M Parlett-Pelleriti ◽

Seung Min Moon ◽

Michelle Evans ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Cognitive Domain ◽

Memory Training ◽

Healthy Older Adults ◽

Cognitive Domains ◽

Randomized Controlled ◽

Effective Interventions ◽

Age Related ◽

Before And After

Abstract Objective The majority of the population will experience some cognitive decline with age. Therefore, the development of effective interventions to mitigate age-related decline is critical for older adults’ cognitive functioning and their quality of life. Methods In our randomized controlled multisite trial, we target participants’ working memory (WM) skills, and in addition, we focus on the intervention’s optimal scheduling in order to test whether and how the distribution of training sessions might affect task learning, and ultimately, transfer. Healthy older adults completed an intervention targeting either WM or general knowledge twice per day, once per day, or once every-other-day. Before and after the intervention and 3 months after training completion, participants were tested in a variety of cognitive domains, including those representing functioning in everyday life. Results In contrast to our hypotheses, spacing seems to affect learning only minimally. We did observe some transfer effects, especially within the targeted cognitive domain (WM and inhibition/interference), which remained stable at the 3-month follow-up. Discussion Our findings have practical implications by showing that the variation in training schedule, at least within the range used here, does not seem to be a crucial element for training benefits.

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Undetected Neurodegenerative Disease Biases Estimates of Cognitive Change in Older Adults

Psychological Science ◽

10.1177/0956797620985518 ◽

2021 ◽

pp. 095679762098551

Author(s):

Karra D. Harrington ◽

Andrew J. Aschenbrenner ◽

Paul Maruff ◽

Colin L. Masters ◽

Anne M. Fagan ◽

...

Keyword(s):

Older Adults ◽

Neurodegenerative Disease ◽

Cognitive Change ◽

Rate Of Change ◽

Cognitive Domain ◽

Cognitively Normal ◽

Healthy Older Adults ◽

Memory Processing ◽

Cerebrospinal Fluid Biomarkers ◽

Β Amyloid

Neurodegenerative disease is highly prevalent among older adults and, if undetected, may obscure estimates of cognitive change among aging samples. Our aim in this study was to determine the nature and magnitude of cognitive change in the absence of common neuropathologic markers of neurodegenerative disease. Cognitively normal older adults (ages 65–89 years, N = 199) were classified as normal or abnormal using neuroimaging and cerebrospinal-fluid biomarkers of β-amyloid, tau, and neurodegeneration. When cognitive change was modeled without accounting for biomarker status, significant decline was evident for semantic memory, processing speed, and working memory. However, after adjusting for biomarker status, we found that the rate of change was attenuated and that the biomarker-normal group demonstrated no decline for any cognitive domain. These results indicate that estimates of cognitive change in otherwise healthy older adults will be biased toward decline when the presence of early neurodegenerative disease is not accounted for.

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Mild behavioral impairment as a predictor of cognitive functioning in older adults

International Psychogeriatrics ◽

10.1017/s1041610220000678 ◽

2020 ◽

pp. 1-9

Author(s):

Hillary J. Rouse ◽

Brent J. Small ◽

John A. Schinka ◽

David A. Loewenstein ◽

Ranjan Duara ◽

...

Keyword(s):

Older Adults ◽

Executive Function ◽

Episodic Memory ◽

Short Term Memory ◽

Secondary Data ◽

Cognitive Status ◽

Cognitive Domain ◽

Behavioral Impairment ◽

Healthy Older Adults ◽

Cognitive Domains

ABSTRACT Objective: To assess the influence of mild behavioral impairment (MBI) on the cognitive performance of older adults who are cognitively healthy or have mild cognitive impairment (MCI). Methods: Secondary data analysis of a sample (n = 497) of older adults from the Florida Alzheimer’s Disease Research Center who were either cognitively healthy (n = 285) or diagnosed with MCI (n = 212). Over half of the sample (n = 255) met the operationalized diagnostic criteria for MBI. Cognitive domains of executive function, attention, short-term memory, and episodic memory were assessed using a battery of neuropsychological tests. Results: Older adults with MBI performed worse on tasks of executive function, attention, and episodic memory compared to those without MBI. A significant interaction revealed that persons with MBI and MCI performed worse on tasks of episodic memory compared to individuals with only MCI, but no significant differences were found in performance in cognitively healthy older adults with or without MBI on this cognitive domain. As expected, cognitively healthy older adults performed better than individuals with MCI on every domain of cognition. Conclusions: The present study found evidence that independent of cognitive status, individuals with MBI performed worse on tests of executive function, attention, and episodic memory than individuals without MBI. Additionally, those with MCI and MBI perform significantly worse on episodic memory tasks than individuals with only MCI. These results provide support for a unique cognitive phenotype associated with MBI and highlight the necessity for assessing both cognitive and behavioral symptoms.

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Partner-Specific Communication Deficits in Individuals With Alzheimer's Disease

American Journal of Speech-Language Pathology ◽

10.1044/2020_ajslp-19-00094 ◽

2020 ◽

pp. 1-15

Author(s):

Eun Jin Paek ◽

Si On Yoon

Keyword(s):

Alzheimer’S Disease ◽

Older Adults ◽

Alzheimer's Disease ◽

Referential Communication ◽

Sorting Task ◽

Audience Design ◽

Healthy Older Adults ◽

Communication Task ◽

Design Skills ◽

Referential Expressions

Purpose Speakers adjust referential expressions to the listeners' knowledge while communicating, a phenomenon called “audience design.” While individuals with Alzheimer's disease (AD) show difficulties in discourse production, it is unclear whether they exhibit preserved partner-specific audience design. The current study examined if individuals with AD demonstrate partner-specific audience design skills. Method Ten adults with mild-to-moderate AD and 12 healthy older adults performed a referential communication task with two experimenters (E1 and E2). At first, E1 and participants completed an image-sorting task, allowing them to establish shared labels. Then, during testing, both experimenters were present in the room, and participants described images to either E1 or E2 (randomly alternating). Analyses focused on the number of words participants used to describe each image and whether they reused shared labels. Results During testing, participants in both groups produced shorter descriptions when describing familiar images versus new images, demonstrating their ability to learn novel knowledge. When they described familiar images, healthy older adults modified their expressions depending on the current partner's knowledge, producing shorter expressions and more established labels for the knowledgeable partner (E1) versus the naïve partner (E2), but individuals with AD were less likely to do so. Conclusions The current study revealed that both individuals with AD and the control participants were able to acquire novel knowledge, but individuals with AD tended not to flexibly adjust expressions depending on the partner's knowledge state. Conversational inefficiency and difficulties observed in AD may, in part, stem from disrupted audience design skills.

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Talk or Walk? Gait Speed over Self-Report in Association with Cognitive Speed in Healthy Older Adults

GeroPsych ◽

10.1024/1662-9647/a000202 ◽

2019 ◽

Vol 32 (1) ◽

pp. 41-52

Author(s):

Matthew C. Costello ◽

Shane J. Sizemore ◽

Kimberly E. O’Brien ◽

Lydia K. Manning

Keyword(s):

Older Adults ◽

Older Adult ◽

Gait Speed ◽

Well Being ◽

Self Report ◽

Subjective Report ◽

Healthy Older Adults ◽

Relative Value ◽

Cognitive Speed ◽

Age Range

Abstract. This study explores the relative value of both subjectively reported cognitive speed and gait speed in association with objectively derived cognitive speed. It also explores how these factors are affected by psychological and physical well-being. A group of 90 cognitively healthy older adults ( M = 73.38, SD = 8.06 years, range = 60–89 years) were tested in a three-task cognitive battery to determine objective cognitive speed as well as measures of gait speed, well-being, and subjective cognitive speed. Analyses indicated that gait speed was associated with objective cognitive speed to a greater degree than was subjective report, the latter being more closely related to well-being than to objective cognitive speed. These results were largely invariant across the 30-year age range of our older adult sample.

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