Mitochondrial Health, Physical Functioning, and Daily Affect: Bioenergetic Mechanisms of Dementia Caregiver Well-Being.

OBJECTIVE: Chronic stress adversely affects mental and physical well-being. However, health outcomes vary among people experiencing the same stressor. Individual differences in physical and emotional well-being may depend on mitochondrial biology, as energy production is crucial for stress regulation. This study investigated whether mitochondrial respiratory capacity corresponds to individual differences in dementia spousal caregivers' mental and physical health. METHODS: Spousal caregivers of individuals with Alzheimer's disease and related dementias ( N = 102, mean age = 71, 78% female, 83% White) provided peripheral blood samples and completed self-report questionnaires on quality of life, caregiver burden, and a 7-day affect scale. Multiple and mixed linear regressions were used to test the relationship between mitochondrial biology and well-being. RESULTS: Spare respiratory capacity ( b = 12.76, confidence interval [CI] = 5.23-20.28, p = .001), maximum respiratory capacity ( b = 8.45, CI = 4.54-12.35, p < .0001), and ATP-linked respiration ( b = 10.11, CI = 5.05-15.18, p = .0001) were positively associated with physical functioning. At average ( b = -2.23, CI = -3.64 to -0.82, p = .002) and below average ( b = -4.96, CI = -7.22 to 2.70, p < .0001) levels of spare respiratory capacity, caregiver burden was negatively associated with daily positive affect. At above average levels of spare respiratory capacity, caregiver burden was not associated with positive affect ( p = .65). CONCLUSIONS: Findings suggest that higher mitochondrial respiratory capacity is associated with better psychological and physical health-a pattern consistent with related research. These findings provide some of the earliest evidence that cellular bioenergetics are related to well-being.

Differential Item Functioning and Clinical Utility of the Subjective Memory Complaints Questionnaire in a Multi-Ethnic Cohort.

INTRODUCTION: This study evaluated psychometric properties of the Subjective Memory Complaints Questionnaire (SMCQ) in a non-Hispanic White (NHW) and Mexican American (MA) sample from Texas in the United States. METHODS: Data were obtained from the Health and Aging Brain Study - Health Disparities (HABS-HD; N=1691, age=66.5±8.7, education=12.4±4.8, 60.6% female, 33.2% MA Spanish-speaking). Unidimensionality of the SMCQ was evaluated with confirmatory factor analysis. Differential item functioning (DIF) of the SMCQ was assessed across age, sex, education, and ethnicity/language using item response theory (IRT) / logistic ordinal regression. Associations of the SMCQ in relation to cognitive status, Alzheimer's disease (AD) blood-based biomarkers, and psychological distress were examined. RESULTS: The SMCQ showed excellent fit in a single-factor model (CFI=0.97, TLI=0.97, RMSEA [95% CI] = 0.05 [0.04, 0.05], SRMR=0.07). Significant item-level DIF was detected by education level and ethnicity/language, but not by age or sex; when detected, DIF was not salient (i.e., adverse). The SMCQ was associated with greater psychological distress, worse Clinical Dementia Rating scores, and greater disease burden as measured by total tau and neurofilament light. CONCLUSIONS: Practically negligible item-level bias was identified across education and ethnicity/language. Detected DIF can be described as benign, indicating that some items manifested differently between groups but had minimal impact on measurement properties. These results demonstrate that the SMCQ performs appropriately across demographic variables. Our findings also provide support for the associations of SMCQ scores with self-reported mood, cognitive status, and AD blood-based biomarkers.

The Relationship Between Apathy and Cognitive Impairment Among Hispanic/Latin Americans: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses Systematic Review.

OBJECTIVES: The primary aim was to evaluate apathy assessment measures in relation to cognitive impairment among Hispanic/Latin Americans. METHODS: A systematic review on the relationship between apathy and cognitive impairment among Hispanic/Latin Americans across normal aging and neurocognitive disorders was conducted according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and using APA PsycInfo, Embase, and PubMed databases. Inclusion criteria required (1) a sample of English or Spanish-speaking adults ages 18 years and older, (2) with measures of apathy, (3) assessment of cognitive functioning or diagnosis of neurocognitive disorder, (4) with at least 18.5% Hispanic/Latin American represented in the sample. RESULTS: Only 14 papers met criteria to be included in this review. Of the 12 cross-sectional studies, 9 demonstrated significant associations between increased apathy and cognitive impairment, 1 demonstrated a descriptive difference between apathy and cognitive status (ie, no hypothesis test conducted), while 2 demonstrated null effects. These cross-sectional studies consisted of community and clinic samples of participants across North and South America. Two longitudinal studies conducted in North America demonstrated non-significant associations of apathy with cognitive status. CONCLUSIONS: The Neuropsychiatric Inventory (NPI) and Neuropsychiatric Inventory Questionnaire (NPI-Q) apathy subscales were the most used measures for apathy in this review (85.7% of included studies). However, validity evidence from a review of apathy measures has warranted caution against the use of the NPI outside the context of screening for apathy. This potential measurement bias with Hispanic/Latin Americans apathy research limits conclusions drawn from the present review.

Optimal outbreeding is shaped during larval life-history in the splash pool copepod Tigriopus californicus.

Inbreeding and outbreeding depression are dynamic forms of selection critical to mating system evolution and the efficacy of conservation biology. Most evidence on how the relative severity and timing of these forces are shaped is confined to self-fertilization, distant outcrossing, and intermediate 'optimal outcrossing' in hermaphrodites. We tested the notion that closed population demographics may reduce and delay the costs of inbreeding relative to distant outbreeding in an intertidal copepod with separate sexes and a biphasic larval / post-metamorphic life-history (Tigriopus californicus). At three lifecycle stages (fecundity, metamorphosis, and post-metamorphosis), we quantified the effects of inbreeding and outbreeding in crosses with varying degrees of recent common ancestry. Although inbreeding and outbreeding depression have distinct genetic mechanisms, both manifested the same stage-specific consequences for fitness. Inbreeding and outbreeding depression were not apparent for fecundity, post-metamorphic survival, sex ratio, or the ability to acquire mates, but inbreeding between full siblings and outbreeding between interpopulation hybrids reduced the fraction of offspring that completed metamorphosis by 32% and 47%, respectively. On average, the effects of inbreeding on metamorphic rate were weaker and nearly twice as variable among families than those of outbreeding, suggesting genetic load was less pervasive than the incompatibilities accrued between divergent populations. Overall, our results indicate the transition from larval to juvenile life stages is markedly susceptible to both inbreeding and outbreeding depression in T. californicus. We suggest stage-specific selection acting concurrently with the timing of metamorphosis may be an instrumental factor shaping reproductive optima in species with complex life-histories.

Hippocampal, basal ganglia and olfactory connectivity contribute to cognitive impairments in Parkinson's disease.

Cognitive impairment is increasingly recognized as a characteristic feature of Parkinson's disease (PD), yet relatively little is known about its underlying neurobiology. Previous investigations suggest that dementia in PD is associated with subcortical atrophy, but similar studies in PD with mild cognitive impairment have been mixed. Variability in cognitive phenotypes and diversity of PD symptoms suggest that a common neuropathological origin results in a multitude of impacts within the brain. These direct and indirect impacts of disease pathology can be investigated using network analysis. Functional connectivity, for instance, may be more sensitive than atrophy to decline in specific cognitive domains in the PD population. Fifty-eight participants with PD underwent a neuropsychological test battery and scanning with structural and resting state functional MRI in a comprehensive whole-brain association analysis. To investigate atrophy as a potential marker of impairment, structural gray matter atrophy was associated with cognitive scores in each cognitive domain using voxel-based morphometry. To investigate connectivity, large-scale networks were correlated with voxel time series and associated with cognitive scores using distance covariance. Structural atrophy was not associated with any cognitive domain, with the exception of visuospatial measures in primary sensory and motor cortices. In contrast, functional connectivity was associated with attention, executive function, language, learning and memory, visuospatial, and global cognition in the bilateral hippocampus, left putamen, olfactory cortex, and bilateral anterior temporal poles. These preliminary results suggest that cognitive domain-specific networks in PD are distinct from each other and could provide a network signature for different cognitive phenotypes.

Recent Advances in Neuropsychological Test Interpretation for Clinical Practice.

Much attention in the field of clinical neuropsychology has focused on adapting to the modern healthcare environment by advancing telehealth and promoting technological innovation in assessment. Perhaps as important (but less discussed) are advances in the development and interpretation of normative neuropsychological test data. These techniques can yield improvement in diagnostic decision-making and treatment planning with little additional cost. Brooks and colleagues (Can Psychol 50: 196-209, 2009) eloquently summarized best practices in normative data creation and interpretation, providing a practical overview of norm development, measurement error, the base rates of low scores, and methods for assessing change. Since the publication of this seminal work, there have been several important advances in research on development and interpretation of normative neuropsychological test data, which may be less familiar to the practicing clinician. Specifically, we provide a review of the literature on regression-based normed scores, item response theory, multivariate base rates, summary/factor scores, cognitive intraindividual variability, and measuring change over time. For each topic, we include (1) an overview of the method, (2) a rapid review of the recent literature, (3) a relevant case example, and (4) a discussion of limitations and controversies. Our goal was to provide a primer for use of normative neuropsychological test data in neuropsychological practice.

Does neurocognition contribute to age-related deficits in the online navigation of electronic patient health portals?

OBJECTIVE: The internet serves an increasingly critical role in how older adults manage their personal health. Electronic patient portals, for example, provide a centralized platform for older adults to access lab results, manage prescriptions and appointments, and communicate with providers. This study examined whether neurocognition mediates the effect of older age on electronic patient portal navigation. METHOD: Forty-nine younger (18-35 years) and 35 older adults (50-75 years) completed the Test of Online Health Records Navigation (TOHRN), which is an experimenter-controlled website on which participants were asked to log-in, review laboratory results, read provider messages, and schedule an appointment. Participants also completed a neuropsychological battery, self-report questionnaires, and measures of health literacy and functional capacity. RESULTS: Mediation analyses revealed a significant indirect effect of older age on lower TOHRN accuracy, which was fully mediated by the total cognitive composite. CONCLUSIONS: Findings indicate that neurocognition may help explain some of the variance in age-related difficulties navigating electronic patient health portals. Future studies might examine the possible benefits of both structural (e.g., human factors web design enhancement) and individual (e.g., training and compensation) cognitive supports to improve the navigability of electronic patient health portals for older adults.

Are accuracy discernment and sharing of COVID-19 misinformation associated with older age and lower neurocognitive functioning?

The online proliferation of COVID-19 misinformation led to adverse health and societal consequences. This study investigated possible differences in COVID-19 headline accuracy discernment and online sharing of COVID-19 misinformation between older and younger adults, as well as the role of individual differences in global cognition, health literacy and verbal IQ. Fifty-two younger (18-35 years old) and fifty older adults (age 50 and older) completed a neurocognitive battery, health literacy and numeracy measures, and self-report questionnaires via telephone. Participants also completed a social media headline-sharing experiment (Pennycook et al., Psychological science, 31(7), 770-780, 2020) in which they were presented with true and false COVID-19 headlines about which they indicated: 1) the likelihood that they would share the story on social media; and 2) the factual accuracy of the story. A repeated measures multivariate analysis of variance controlling for gender and race/ethnicity showed no effects of age (p = .099) but a significant interaction between actual COVID-19 headline accuracy and the likelihood of sharing (p < .001), such that accuracy was more strongly related to sharing false headlines (r = -.64) versus true headlines (r = -.43). Moreover, a higher likelihood of sharing false COVID-19 headlines was associated with lower verbal IQ and numeracy skills in older adults (rs = -.51--.40) and with lower verbal IQ, numeracy, and global cognition in younger adults (rs = -.66--.60). Findings indicate that headline accuracy judgements, numeracy, and verbal IQ are important contributors to sharing COVID-19 misinformation in both older and younger adults. Future work might examine the benefits of psychoeducation for improving health and science literacy for COVID-19. Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-023-04464-w.

Combined effects of older age and HIV disease on changes in everyday functioning over one year.

Older age and HIV disease are independent risk factors for problems in many aspects of everyday functioning. However, less is known about how these risk factors may combine to influence everyday functioning over time. The current study examined the possible combined effects of age and HIV serostatus on change in everyday functioning over a 1-year period and its specific associations with changes in neurocognition. A repeated measures factorial design was employed. Participants included 77 older persons with HIV (PWH), 35 younger PWH, 44 older HIV-, and 27 younger HIV-adults who each completed baseline and follow-up visits approximately 14 months apart. Everyday functioning was assessed using a standardized self-report measure of activities of daily living (ADLs) at each visit. A comprehensive clinical battery assessed six domains of neurocognition. Raw scores on each neurocognitive measure were converted to sample-based z-scores, from which a global neurocognitive z-score was derived. Older PWH reported the poorest everyday functioning at baseline and follow-up visits at medium-to-large effect sizes. However, these ADL disruptions among older PWH were relatively stable over time, differing significantly from younger PWH who evidenced mild ADL improvements from baseline to follow-up. Within the entire sample, everyday functioning at baseline predicted neurocognitive performance at follow-up, but the reciprocal relationship was not significant. Older adults with HIV have high rates of ADL problems, which appear stable over 1 year, the trajectory of which differed from younger adults with HIV for whom mild improvements were observed. Importantly, the results also suggest that problems with ADLs may sometimes precede neurocognitive declines. Further examination of longitudinal data is needed to elucidate the long-term trajectory of neurocognitive and functional changes in older PWH to support early detection and proper management of clinical care.

Addressing the disparities in dementia risk, early detection and care in Latino populations: Highlights from the second Latinos & Alzheimer's Symposium.

The Alzheimer's Association hosted the second Latinos & Alzheimer's Symposium in May 2021. Due to the COVID-19 pandemic, the meeting was held online over 2 days, with virtual presentations, discussions, mentoring sessions, and posters. The Latino population in the United States is projected to have the steepest increase in Alzheimer's disease (AD) in the next 40 years, compared to other ethnic groups. Latinos have increased risk for AD and other dementias, limited access to quality care, and are severely underrepresented in AD and dementia research and clinical trials. The symposium highlighted developments in AD research with Latino populations, including advances in AD biomarkers, and novel cognitive assessments for Spanish-speaking populations, as well as the need to effectively recruit and retain Latinos in clinical research, and how best to deliver health-care services and to aid caregivers of Latinos living with AD.