Assessing Discrepancies in Neurocognitive and Patient-Reported Measures of Brain Tumor Survivors.

OBJECTIVES: To examine the association between performance-based neurocognitive and patient-reported cognitive function tests and identify characteristics that may explain observed discrepancies as a means to advance intervention development. SAMPLE & SETTING: 40 adults diagnosed with a primary brain tumor (PBT) (high-grade, n = 35) were recruited from two academic neuro-oncology clinics in North Carolina. METHODS & VARIABLES: Eligibility included a Mini-Mental State Examination score of 24 or greater, having completed cancer treatment, and having tumor stability. Participants completed performance-based neurocognitive and patient-reported cognitive function, demographic, and symptom assessment tests at one time point. RESULTS: Neurocognitive impairments included executive control, memory, and attention. Age, time since diagnosis, and tumor- or treatment-specific variables were not associated with neurocognitive or patient-reported cognitive function. Those reporting worse cognitive impairment tended also to report greater severity of PBT-specific and depressive symptoms. IMPLICATIONS FOR NURSING: Patient-reported cognitive concerns warrant additional assessment for potential interventions to maintain function.

Cerebral oxygenation in wake and during sleep and its relationship to cognitive function in community-dwelling older adults without sleep disordered breathing.

BACKGROUND: This descriptive cross-sectional study investigated the relationships between cerebral oxygen reserve and cognitive function in community-dwelling older adults. METHODS: Participants (72 women and 40 men) underwent standard polysomnography, including regional measures of percent oxyhemoglobin saturation (rcSO(2)) determined by cerebral oximetry. Two variables were used to calculate cerebral oxygen reserve: (a) awake rcSO(2) (mean presleep rcSO(2)) and (b) the change in rcSO(2) from before sleep to the end of the first non-rapid-eye movement cycle. General linear models, adjusted for the effects of education and occupation, tested differences in performance on standard tests of memory, attention, and speed of mental processing. RESULTS: Awake rcSO(2) values were normal (60%-79.9%) in 64 participants, marginal (50%-59.9%) in 41, and low (43%-49.9%) in 7. Participants with normal awake levels had higher cognitive function than those with low levels (p < .05). Changes in rcSO(2) were greatest in participants with marginal awake rcSO(2) values; among whom, those who increased rcSO(2) during sleep (n = 17) had better memory function than the 24 who did not (p < .05). CONCLUSIONS: Low awake rcSO(2) values mark individuals with low cerebral oxygen reserves and generally lower cognitive function; marginal awake rcSO(2) values that fall during sleep may indicate loss of cerebral oxygen reserve and an increased risk for cognitive decline. Further studies may clarify the significance of and mechanisms underlying individual differences in awake rcSO(2) and the changes that occur in rcSO(2) while asleep.

Cerebrovascular disease and patterns of cerebral oxygenation during sleep in elders.

PURPOSE: The aim of this descriptive exploratory study was to describe patterns of cerebral oxygen reserves during sleep and their association with cerebrovascular risk factors in elders. METHOD: Participants--115 elders, age 70+ years--were monitored overnight using standard polysomnography. Measures included arterial oxyhemoglobin (SaO2) and regional measures of percentage of cerebral oxyhemoglobin saturation (rcSO2) via cerebral oximetry. Participants were classified based on the magnitude of change in rcSO2 from resting baseline to the end of the first nonrapid-eye-movement (NREM) period. One-way ANOVA and Chi-square were used to test group differences in SaO2 and the prevalence of cerebrovascular risk factors. FINDINGS: 20 participants (Group 1) experienced an increase in rcSO2 during sleep along with sleeping rcSO2 levels >or= 55%; 95 participants experienced a decline in rcSO2; 72 participants (Group 2) had sleeping rcSO2 levels >or= 55%; and 23 participants had sleeping rcSO2 levels <55% (Group 3). Although all three groups had equivalent declines in SaO2 levels during sleep, Group 3 had more cardiovascular comorbidity than Groups 1 and 2. CONCLUSIONS: Although SaO2 levels decline in most people during sleep, compensatory vascular responses to these drops in SaO2 are important for preventing rcSO2 from falling during sleep. Those entering sleep with lower baseline rcSO2 levels and those with greater declines in cerebral oxygenation during sleep may have greater cardiovascular burden and be at greater risk for stroke and other forms of disabling cerebrovascular disease.

Delirium resolution in hospitalized older patients with cancer.

Delirium is a troubling complication in hospitalized older patients with cancer. Although preventable and potentially reversible, delirium may be prolonged. Persistent delirium at the time of hospital discharge is common and associated with multiple adverse outcomes. We conducted a secondary data analysis to examine delirium resolution in 43 hospitalized older patients with cancer who had prevalent or incident delirium. We describe trajectories of delirium resolution and evaluate differences in patients with and without delirium resolution. Delirium was assessed using the NEECHAM confusion scale. Forty-one of the 43 patients had delirium during hospitalization before discharge; 2 had delirium only at the time of discharge. Although delirium resolved in 13 patients, a significant majority (70%) had delirium at discharge. Patients with delirium resolution were less functionally impaired before hospitalization and exhibited fewer etiologic risk patterns at admission. Mild delirium was more likely to resolve than severe delirium. All patients with chronic cognitive impairment had persistent delirium. Care for hospitalized older patients with cancer should incorporate delirium prevention and intervention strategies. Caregiver education, communication between providers, and follow-up are critical when delirium persists. Additional research focusing on the management and impact of persistent delirium in hospitalized older patients with cancer is needed.

Exploratory analysis of cerebral oxygen reserves during sleep onset in older and younger adults.

OBJECTIVES: To explore differences in cerebral oxygen reserves during sleep in old and young adults. DESIGN: Descriptive cross-sectional study. SETTING: General clinical research center. PARTICIPANTS: Nine old (aged 65-84) and 10 young (aged 21-39) adults. MEASUREMENTS: Subjects were monitored during the first nightly sleep cycle using standard polysomnography, including measures of arterial oxyhemoglobin saturation (SaO(2)). Changes in regional cerebral oxyhemoglobin saturation (rcSO(2)) were used to estimate cerebral oxygen reserves. General linear models were used to test group differences in the change in SaO(2) and rcSO(2) during sleep. RESULTS: Older subjects had lower SaO(2) than young subjects before sleep (baseline) (F((1,18))=5.1, P=.04) and during sleep (F((1,18))=10.7, P=.01). During sleep, half of the older subjects and none of the younger ones had SaO(2) values below 95%. In addition, the older subjects had more periods of oxygen desaturation (drops in SaO(2) > or = 4%) (chi-square=24.3, P=.01) and lower SaO(2) levels during desaturation (F((1,18))=11.1, P<.01). Although baseline values were similar, rcSO(2) decreased during sleep 2.1% in older subjects (F((1,8))=3.8, P=.05) but increased 2.1% during sleep in younger subjects (F((1,9))=4.6, P=.04). When the older subjects awakened from sleep, rcSO(2), but not SaO(2), returned to baseline; both returned to baseline in younger subjects. CONCLUSION: This exploratory analysis generated the hypothesis that lower SaO(2), combined with declines in regional blood flow, contributes to decline in cerebral oxygen reserves during sleep in older subjects. Further study will assess the effects of factors (e.g., medical conditions, subclinical disorders, and sleep architecture) that might account for these differences.

Tailoring protocols to successfully recruit and retain older adults in a longitudinal study of sleep and cognition.

Many studies attest to the challenges of recruiting and retaining older adults in longitudinal studies. This article presents the methods used by the Physiological Research to Improve Sleep and Memory project to recruit and retain 115 adults (age 70 and older) in a 2-year study that involved annual administrations of two neurocognitive test batteries and two nights of polysomnography. Strategies built on knowledge obtained from participant informants and the use of tailored, individualized protocols are described. Together, these strategies enabled participants to become vested in the research process and to fully participate in all aspects of the study.

Respiratory periodicity and electroencephalogram arousals during sleep in older adults.

The aim of this exploratory study was to examine the relationship of electroencephalogram (EEG) arousals to breathing patterns and the relationship of both arousals and breathing patterns to arterial oxygenation during sleep in older adults. Five older adults were monitored using standard polysomnography. Records were divided into 5-min segments and breathing patterns identified based on the level of respiratory periodicity and the variability in the frequency of breathing cycles. Standard criteria were used to determine sleep states and occurrence of EEG arousals. High respiratory periodicity was seen in 23% of the segments, whereas 24% had low respiratory periodicity with minimal variability in the frequency of breathing (Type A low respiratory periodicity) and 53% had low respiratory periodicity with high variability in the frequency of breathing (Type B low respiratory periodicity). Nearly all (97%) segments with high respiratory periodicity had EEG arousals, whereas fewer segments (33%) with low respiratory periodicity had arousals, regardless of the stage of sleep. Desaturations occurred more often in segments with high respiratory periodicity, F((2,4)) = 57.3, p < .001, but overall, the mean SaO(2) of segments with high respiratory periodicity did not differ from levels seen in segments with low respiratory periodicity, F((2,4)) = 0.77, ns. Our findings suggest that high respiratory periodicity is a common feature of EEG arousals and, in older adults, may be important for maintaining oxygen levels during desaturations during sleep.

Delirium in hospitalized older patients with cancer.

PURPOSE/OBJECTIVES: To examine key aspects of delirium in a sample of hospitalized older patients with cancer. DESIGN: Secondary analysis of data from studies on acute confusion in hospitalized older adults. SETTING: Tertiary teaching hospital in the southeastern United States. SAMPLE: 76 hospitalized older patients with cancer (mean age = 74.4 years) evenly divided by gender and ethnicity and with multiple cancer diagnoses. METHODS: Data were collected during three studies of acute confusion in hospitalized older patients. Delirium was measured with the NEECHAM Confusion Scale on admission, daily during hospitalization, and at discharge. Patient characteristics and clinical risk markers were determined at admission. MAIN RESEARCH VARIABLES: Prevalent and incident delirium, etiologic risk patterns, and patient characteristics. FINDINGS: Delirium was noted in 43 (57%) patients; 29 (38%) were delirious on admission. Fourteen of 47 (30%) who were not delirious at admission became delirious during hospitalization. Delirium was present in 30 patients (39%) at discharge. Most delirious patients had evidence of multiple (mean = 2.3) etiologic patterns for delirium. CONCLUSIONS: Delirium was common in this sample of hospitalized older patients with cancer. Patients with delirium were more severely ill, were more functionally impaired, and exhibited more etiologic patterns than nondelirious patients. IMPLICATIONS FOR NURSING: Nurses caring for older patients with cancer should perform systematic and ongoing assessments of cognitive behavioral performance to detect delirium early. The prevention and management of delirium hinge on the identification and treatment of the multiple risk factors and etiologic mechanisms that underlie delirium. The large number of patients discharged while still delirious has significant implications for posthospital care and recovery.

Evaluation of variables to characterize respiratory periodicity during sleep in older adults.

Reliable markers of early neurological decline might guide interventions to prevent or reverse cognitive decline in older adults. Because cognitive decline is associated with hypoxemia during sleep, the authors examined 3 respiratory periodicity variables in 5 older adults. Subjects were monitored overnight using standard polysomnography. From the inductance band signal, the authors calculated the variability in duration of breathing cycles measured by standard deviation of interbreath intervals (sdIBI), frequency of breathing cycles measured by standard deviation of interbreath frequencies (sdIBF), and amplitude of breathing cycles measured by standard deviation of breathing cycle amplitudes (sdAMP). Logistic regression analysis and kappa coefficients identified variables that reliably detected 5-minute segments having central or obstructive apneas or body movements. An sdIBF > or = 4.5 cpm identified body movements (sensitivity = 0.96, specificity = 0.96, kappa = 0.90). An sdIBI > 1.2 seconds identified central apneas (sensitivity = 0.86, specificity = 0.99, kappa = 0.86), and an sdIBI > or = 1.68 seconds identified segments with 3 central apneas (sensitivity = 0.90, specificity = 0.89, kappa = 0.89). An sdAMP > or = 0.1 V and an sdIBF > or = 1.5 cpm identified obstructive apneas (kappa = 0.91). Data support the potential of these variables to identify central and obstructive apneas and to classify individuals according to different patterns of respiratory periodicity.