Actigraphic and Self-reported Sleep Measures in Older Adults: Factor Analytic Study.

Actigraphy has been used to measure older adults' sleep, but few studies have evaluated the factor structure among actigraphy-measured sleep parameters. Additionally, previous studies have reported the association between actigraphy-measured and self-reported sleep parameters in older adults but have not controlled for covariates of gender, insomnia, cognitive impairment, depression, and health conditions. We therefore investigated the factor structure of actigraphy-measured sleep parameters and, controlling for covariates, the association between actigraphy-measured and self-reported sleep parameters in 62 older adults (female: 75.8%; mean age: 69.9). The factor analysis gave a three-factor solution: length of wakefulness during sleep, sleep disruption, and total sleep time. Self-reported sleep parameters and covariates explained actigraphy-measured total sleep time (explained variance: 61%) substantially more than length of wakefulness during sleep (explained variance: 14%) and sleep disruption (explained variance: 11%). Studies need to select sleep measures based on their focus to best understand sleep characteristics in healthy older adults.

Sleep-Wake Disturbances and Episodic Memory in Older Adults.

Sleep-wake disturbances have been associated with episodic memory loss, but past studies were limited by use of single measures of objective or perceived disturbances. Notably, cognitive reserve and depressive symptoms have been associated with sleep-wake disturbances and poorer episodic memory in older adults. The aims of this study were to determine the relationship between episodic memory and sleep-wake disturbances using objective and perceived measures in older adults and to examine cognitive reserve and depressive symptoms as moderators of this relationship. In this descriptive study, 62 healthy older adults (mean age: 69.9 years; 75.8% women) were recruited from the University of Michigan Clinical Research Program. Objective sleep-wake disturbances were measured by 7-day actigraphy and perceived sleep-wake disturbances by the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale. Episodic memory was measured by the Hopkins Verbal Learning Test-Revised. Analyses involved Pearson's correlation coefficients and hierarchical multiple regression. Results showed that more objectively measured sleep disruption was associated with poorer episodic memory and more perceived daytime sleepiness was associated with better episodic memory. Cognitive reserve and depressive symptoms were not moderators of this relationship. In this study, the relationship between sleep-wake disturbances and episodic memory differed by type of measure, objective or perceived. Future studies are needed using multiple measures of episodic memory to further understand the sleep-wake disturbances and episodic memory relationship in a larger diverse sample of healthy older adults.

An Integrative Review of Brain-Derived Neurotrophic Factor and Serious Cardiovascular Conditions.

BACKGROUND: There is emerging evidence that supports a role for brain-derived neurotrophic factor (BDNF) in the risk and presence of serious cardiovascular conditions. However, few existing literature reviews methodically describe empirical findings regarding this relationship. OBJECTIVES: The purpose of this integrative review was to (a) evaluate BDNF (serum/plasma BDNF levels, BDNF Val66Met genotype) among humans at risk for or with serious cardiovascular conditions and (b) investigate the relationship between BDNF and risk/presence of serious cardiovascular conditions in humans. METHODS: An integrative review was conducted. Articles in English included human subjects, a measure of BDNF levels or BDNF gene, serious cardiovascular conditions, and quantitative data analyses. The search resulted in 475 unique titles, with the final sample including 35 articles representing 30 studies. Articles that received "good" or "fair" ratings (n = 31) using the National Heart, Lung, and Blood Institute Study Quality Assessment Tools were included for synthesis. RESULTS: The retrieved articles were largely nonexperimental, with sample sizes ranging from 20 to 5,510 participants. Overall, BDNF levels were lower in patients with chronic heart failure and stroke, but higher in patients with unstable angina and recent myocardial infarction. Lower BDNF levels were associated with higher incidence of cardiovascular events in patients with a prior history of serious cardiovascular conditions and decreased cardiovascular risk in healthy samples. For BDNF genotype, on average, 36.3% of participants had Met alleles. The frequency of the BDNF Met allele varied across race/ethnicity and cardiovascular conditions and in terms of association with serious cardiovascular condition incidence/risk. DISCUSSION: These findings indicate an emerging area of science. Future investigation is needed on serious cardiovascular condition phenotypes in relationship to BDNF in the same study conditions. Results also suggest for use of standardized BDNF measurement across studies and additional investigation in cardiovascular inflammatory processes that affect BDNF. Moreover, within specific populations, the frequency of Met alleles may be too low to be detected in sample sizes normally found in these types of studies.

Integrative Review of the Relationship Between Sleep Disturbances and Episodic Memory in Older Adults.

Impaired episodic memory in older adults has been linked to many factors. One of these factors is sleep disturbances, which are reported by more than 50% of older adults. The relationship between episodic memory and sleep disturbances remains unclear, however, because of the multiple types of measures of sleep and episodic memory used in previous studies. The purpose of this integrative literature review was to integrate and compare findings on this relationship in adults aged 65 years. An electronic search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature, PsychINFO, and Medline for material published from the inception of the databases to December 2016. The literature search produced 13 data-based, peer-reviewed, and primary research articles that met eligibility criteria. The synthesized results from these articles provide evidence that older adults with 6-8 hr of self-reported total sleep time had better episodic memory than older adults with ≤5 hr or ≥9 hr of total sleep time. Shorter length and lower percentage of slow-wave sleep were associated with reduced episodic memory in older adults, but the results were controversial. Selection of different measurements and inconsistent variables across studies increased the difficulty of synthesizing and comparing the results. The diversity of covariates controlled in the included articles raise questions regarding which covariates should be controlled in such studies of sleep and episodic memory in older adults. The numerous study limitations were thus major barriers to understanding the relationship between sleep disturbances and episodic memory.

Heart failure and skilled nursing facilities: review of the literature.

BACKGROUND: Almost one-fourth of older adults hospitalized with heart failure (HF) are discharged to skilled nursing facilities (SNFs). The purpose of this review was to evaluate knowledge about HF patients discharged to SNFs to provide a foundation for future studies. METHODS AND RESULTS: A search was conducted of Medline, CINAHL, PubMed, and Google Scholar. Key words were heart failure, congestive heart failure, skilled care, skilled nursing care, skilled nursing facilities, nursing home, postacute care, postacute services, and subacute care. Publications (n = 37) were reviewed and categorized into case studies, editorials, clinical care, evaluation projects, and data-based publications. Of 29 data-based publications, 6 were focused on factors associated with hospital readmission from postacute settings, 3 on trends in hospitalizations, 12 on hospital discharge to postacute services, 5 on rehabilitation services in postacute settings, 1 on cost, and 2 on interventions. Patients discharged to SNFs were at high risk for mortality and multiple hospitalizations. No HF-specific care or guidelines were found at SNFs. Only 1 study evaluated quality of life at SNFs. CONCLUSIONS: Prospective studies are needed to evaluate the clinical condition of HF patients discharged to SNFs and the interventions they receive.