Janice Knebl

Characterization of Mexican Americans with mild cognitive impairment and Alzheimer's disease

The purpose of the study was to provide characterization of Mexican Americans who meet criteria for Alzheimers disease (AD) and mild cognitive impairment (MCI). For the study, 1,069 participants ages 40 and above who self-identified as either non-Hispanic white (n = 633) or Mexican American (n = 436) were recruited using a community-based participatory research approach. Global cognition was assessed via the Mini-Mental State Examination (MMSE), dementia severity by the Clinical Dementia Rating Scale, and depression via the Geriatric Depression Scale 30-item version. Age, gender, education, ApoE ε4 allele frequency, and diabetic diagnoses were also analyzed. The findings showed that Mexican Americans (normal controls, MCI, and AD) were younger, less highly educated, performed more poorly on the MMSE, endorsed more symptoms of depression, were more likely to be diagnosed with diabetes, and possessed the ApoE ε4 allele less frequently. Age was the only significant risk factor for cognitive dysfunction (AD/MCI) among Mexican Americans (OR = 1.06, 95% CI = 1.03-1.09). Age (B = 0.07, std = 0.02, p < 0.001) and ApoE ε4 presence (B = 0.9, std = 0.4, p = 0.02) were significantly related to increased disease severity. Given the rapidly growing and aging Mexican American population, there is a substantial need for research into cognitive aging, MCI, and AD among this ethnic group. The current findings hold important implications for both clinic and research settings and point to additional research needs.

Total Cholesterol and Neuropsychiatric Symptoms in Alzheimer's Disease: The Impact of Total Cholesterol Level and Gender

Background: Neuropsychiatric symptoms (NPS) in Alzheimers disease (AD) are a major factor in nursing home placement and a primary cause of stress for caregivers. Elevated cholesterol has been linked to psychiatric disorders and has been shown to be a risk factor for AD and to impact disease progression. The present study investigated the relationship between cholesterol and NPS in AD. Methods: Data on cholesterol and NPS from 220 individuals (144 females, 76 males) with mild-to-moderate AD from the Texas Alzheimers Research and Care Consortium (TARCC) cohort were analyzed. The total number of NPS and symptoms of hyperactivity, psychosis, affect and apathy were evaluated. Groups based on total cholesterol (TC; ≥200 vs. <200 mg/dl) were compared with regard to NPS. The impact of gender was also assessed. Results: Individuals with high TC had lower MMSE scores as well as significantly more NPS and more symptoms of psychosis. When stratified by gender, males with high TC had significantly more NPS than females with high TC or than males or females with low TC. Conclusion: The role of elevated cholesterol in the occurrence of NPS in AD appears to be gender and symptom specific. A cross-validation of these findings will have implications for possible treatment interventions, especially for males with high TC.

Odorant Item Specific Olfactory Identification Deficit May Differentiate Alzheimer Disease From Aging

OBJECTIVES To explore whether the ability to recognize specific odorant items is differentially affected in aging versus Alzheimer disease (AD); to refine olfactory identification deficit (OID) as a biomarker of prodromal and early AD. DESIGN Prospective multicenter cross-sectional study with a longitudinal arm. SETTING Outpatient memory diagnostic clinics in New York and Texas. PARTICIPANTS Adults aged 65 and older with amnestic mild cognitive impairment (aMCI) and AD and healthy aging (HA) subjects in the comparison group. MEASUREMENTS Participants completed the University of Pennsylvania Smell Identification Test (UPSIT) and neuropsychological testing. AD-associated odorants (AD-10) were selected based on a model of ordinal logistic regression. Age-associated odorants (Age-10) were identified using a linear model. RESULTS For the 841 participants (234 HA, 192 aMCI, 415 AD), AD-10 was superior to Age-10 in separating HA and AD. AD-10 was associated with a more widespread cognitive deficit across multiple domains, in contrast to Age-10. The disease- and age-associated odorants clustered separately in age and AD. AD-10 predicted conversion from aMCI to AD. CONCLUSIONS Nonoverlapping UPSIT items were identified that were individually associated with age and disease. Despite a modest predictive value of the AD-specific items for conversion to AD, the AD-specific items may be useful in enriching samples to better identify those at risk for AD. Further studies are needed with monomolecular and unilateral stimulation and orthogonal biomarker validation to further refine disease- and age-associated signals.

A depressive endophenotype for predicting cognitive decline among mexican american adults and elders

Background:Late life depression is both a prodromal feature of and risk factor for Alzheimer’s disease (AD); however, identification of those AD patients who suffer from depression-related cognitive dysfunction remains difficult. In previous work, we identified a clinically-defined depressive endophenotype (DepE) that was found to be related to poorer cognition as well as increase risk for MCI and AD across multiple independent cohorts. The goal of this study was to examine the ability of DepE on memory over time. Methods: Baseline and 12 month follow up data were analyzed from 300 participants of the Health and Aging Brain study. DepE scores were dichotomized into two groups (>1⁄42 or <2) and related to change in memory scores over time. Results: ANOVA of total scores revealed significant differences between groups on WMS III Logical Memory 1 (immediate memory) (p < 0.05) in women. No significant differences were found between groups on men or WMS III Logical Memory 2 (long term memory) in either gender. Conclusions:Elevated DepE scores were associated with a decline in immediate verbal memory among women, but not men over 12 months.

Effect of age on performance of task with spatial conflict

We investigated the effect of aging during a dual task paradigm involving a postural and cognitive task. We measured postural sway and performance in a virtual environment. Older adults had increased response times and decreased accuracy compared to younger adults. Compared to young adults, older adults displayed a tighter control of the center of pressure, decreased sway in standing, while performing the spatial conflict task. This suggests that older adults either prioritize postural control over the cognitive task or they adopt a strategy of intentionally decreasing sway to facilitate performance. Results support balance-retraining protocols that start with single tasks and progress to more difficult multiple tasks.

Effect of Age on Performance of Tasks With Spatial Conflict

Attentional selection has an important adaptive role in individuals’ interactions with the environment. Orienting attention over a scene and selecting the object or location to attend to, is necessary for carrying out desired actions. The cognitive processes range from correctly perceiving and interpreting information from different body sensors to planning and coordinating the effectors to produce the desired movement1.Copyright

Effect of Osteopathic Manipulative Treatment Protocol on Balance in the Elderly

The purpose of this study it to understand the effect of Osteopathic Manipulative Treatment (OMT) on vestibular balance control structures. It was hypothesized that following an OMT treatment protocol, elderly patients would show significant improvement in empirical outcome measurements used to quantify postural stability.Copyright