Daily Variation in Sleep Quality is Associated With Health-Related Quality of Life in People With Spinal Cord Injury.

OBJECTIVE: Although sleep difficulties are common after spinal cord injury (SCI), little is known about how day-to-day fluctuations in sleep quality affects health-related quality of life (HRQOL) among these individuals. We examined the effect of sleep quality on same-day HRQOL using ecological momentary assessment methods over a 7-day period. DESIGN: Repeated-measures study involving 7 days of home monitoring; participants completed HRQOL measures each night and ecological momentary assessment ratings 3 times throughout the day; multilevel models were used to analyze data. SETTING: Two academic medical centers. PARTICIPANTS: A total of 170 individuals with SCI (N=170). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Daily sleep quality was rated on a scale of 0 (worst) to 10 (best) each morning. Participants completed end-of-day diaries each night that included several HRQOL measures (Sleep Disturbance, Sleep-related Impairment, Fatigue, Cognitive Abilities, Pain Intensity, Pain Interference, Ability to Participate in Social Roles and Activities, Depression, Anxiety) and ecological momentary assessment ratings of HRQOL (pain, fatigue, subjective thinking) 3 times throughout each day. RESULTS: Multilevel models indicated that fluctuations in sleep quality (as determined by end-of-day ratings) were significantly related to next-day ratings of HRQOL; sleep quality was related to other reports of sleep (Sleep Disturbance; Sleep-related Impairment; Fatigue) but not to other aspects of HRQOL. For ecological momentary assessment ratings, nights of poor sleep were related to worse pain, fatigue, and thinking. Generally, sleep quality showed consistent associations with fatigue and thinking across the day, but the association between sleep quality and these ecological momentary assessment ratings weakened over the course of the day. CONCLUSIONS: Findings highlight the important association between sleep and HRQOL for people with SCI. Future work targeting sleep quality improvement may have positive downstream effects for improving HRQOL in people with SCI.

Measuring Intraventricular Pressure Using Ultrasound Elastography.

OBJECTIVES: Intraventricular pressure (IVP) is one of the most important measurements for evaluating cardiac function, but this measurement is not currently easily assessable in the clinic. The primary reason for this is the absence of a noninvasive technique for measuring IVP. In this study, we investigate the relationship between IVP and dynamic myocardial stiffness measured by shear wave elasticity imaging (SWEI) and assess the feasibility of measuring IVP using SWEI. METHODS: In 8 isolated working rabbit hearts, IVP was recorded in the left ventricle using a pressure catheter. Simultaneously, myocardial stiffness was recorded by SWEI. Using the peak values for IVP and SWEI measured stiffness, SWEI measurements were calibrated and converted to IVP. RESULTS: A linear relationship with zero intercept was observed between IVP and SWEI, with the average slope of 0.318 kPa/mm Hg, R2 = 0.89. Using one point on the IVP/SWEI curve, SWEI measurements were converted to IVP. Estimated pressure using SWEI and IVP were linearly correlated with the slope of 0.95, R2 = 0.88 (mean end diastolic pressure by pressure catheter = 12.716 mm Hg and by SWEI=14.726 mm Hg), indicating the near equivalence of the 2 measurements. CONCLUSION: We have shown that SWEI measurements are linearly related to IVP; therefore, pressure-based indices could potentially be derived from SWEI ultrasound elastography. The feasibility of using SWEI to estimate IVP with a single point calibration was also shown in this study.

The reliability of end of day and ecological momentary assessments of pain and pain interference in individuals with spinal cord injury.

PURPOSE: This study investigated the most efficient means of measuring pain intensity and pain interference comparing ecological momentary assessment (EMA) to end of day (EOD) data, with the highest level of measurement reliability as examined in individuals with spinal cord injury. METHODS: EMA (five times throughout the day) and EOD ratings of pain and pain interference were collected over a 7-day period. Multilevel models were used to examine the reliability for both EOD and EMA assessments in order to determine the amount of variability in these assessments over the course of a week or the day, and a multilevel version of the Spearman-Brown Prophecy formula was used to estimate values for reliability. RESULTS: Findings indicate the minimum of number of EOD and EMA assessments needed to achieve different levels of reliability ("adequate" > 0.70, "good" > 0.80 and excellent > 0.90). In addition, the time of day (either morning, midday or evening) did not impact the estimated reliability for the EMA assessments. CONCLUSIONS: These findings can help researchers and clinician balance the cost/benefit tradeoffs of these different types of assessments by providing specific cutoffs for the numbers of each type of assessment that are needed to achieve excellent reliability.

A Latent Content Analysis of Barriers and Supports to Healthcare: Perspectives From Caregivers of Service Members and Veterans With Military-Related Traumatic Brain Injury.

OBJECTIVE: To identify barriers and supports that caregivers of individuals with military-related traumatic brain injury (TBI) encounter when navigating the military healthcare system; this information will be used as the foundation of a new patient-reported outcome measure. SETTING: Community. PARTICIPANTS: Forty-five caregivers of service members and veterans (SMV) who sustained a medically documented mild, moderate, severe, or penetrating TBI. DESIGN: Latent content analysis. MAIN MEASURES: Nine focus group discussions of barriers and supports to navigating the military healthcare system and community resources. RESULTS: Latent content analysis indicated that caregivers discussed barriers (66%) and supports (34%) to obtaining care within the military healthcare system and the community. Caregivers most frequently discussed SMVs' interactions with healthcare, their own interactions with healthcare, family care, and community organizations. CONCLUSIONS: Caregivers confront numerous challenges while pursuing healthcare services. Although much of the discussion focused on barriers and perceived unmet needs within the military healthcare system, caregivers also recognized supports within the military healthcare system and general community. Increased attention to accessibility and quality of services, as well as reducing financial burden, can lead to improved health-related quality of life for caregivers and their SMVs.

The association between sleep and cognitive function in people with spinal cord injury (SCI).

PURPOSE/OBJECTIVE: While there is evidence in other clinical groups to suggest that sleep problems can negatively impact cognitive performance, this relationship has not yet been examined in people with spinal cord injury (SCI). Thus, we sought to examine the association between sleep and cognitive function in people with SCI. RESEARCH METHOD/DESIGN: Over the course of 7 days, 167 individuals with SCI completed daily subjective ratings of sleep (sleep quality, number of hours slept per night, and bedtime variability) and wore a wrist-worn device that continuously monitored autonomic nervous system (ANS) activity (i.e., blood volume pulse [BVP] signal and electrodermal activity [EDA] signal). At the end of this home monitoring period, participants completed a subjective rating of cognition and six objective cognitive tests. A series of multivariable linear regressions were used to examine associations between eight measures of sleep/ANS activity during sleep and eight cognitive variables. RESULTS: Subjective ratings of sleep were not related to either objective cognitive performance or self-reported cognitive function. However, there were some relationships between ANS activity during sleep and objective cognitive performance: lower BVP signal was associated with poorer performance on measures of processing speed, working memory, learning and long-term memory, and EDA signals were associated with poorer performance on a measure of executive function. CONCLUSIONS/IMPLICATIONS: Future work is needed to better understand the relationship of sleep, especially sleep physiology, and cognitive functioning for individuals with SCI, and how that may be similar or different to relationships in the general population. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Survey response burden in caregivers of civilians and service members/veterans with traumatic brain injury.

PURPOSE: Caregivers have expressed interest in survey research, yet there is limited information available about survey response burden, ie, the time, effort, and other demands needed to complete the survey. This may be particularly important for caregivers due to excessive time demands and/or stress associated with caregiving. METHOD: Survey response burden indicators were collected as part of a study to develop and validate a patient-reported outcome (PRO) measurement system for caregivers of civilians or service members/veterans (SMVs) with traumatic brain injury (TBI). RESULTS: Compared to the group caring for civilians (n=335), the group caring for SMVs (n=123) was comprised of all women, was younger, had fewer racial/ethnic minorities, had more education, and nearly all were the spouse of a person with TBI. All PRO outcomes were poorer for the group caring for SMVs. Although the caregivers of SMVs had poorer PRO outcomes compared to caregivers of civilians, they were more likely to report that they would recommend the study to others. Caregivers with less education and those from racial/ethnic minority groups had more favorable ratings of their study participation experience, even though they needed more help using the computer or answering the questions. CONCLUSION: The results of this study provide useful information about the acceptability of computer-based survey administration for caregiver PROs. PROs are widely gathered in clinical and health services research and could be particularly useful in TBI care programs. More data are needed to determine the best assessment strategies for individuals with lower education who are likely to require some assistance completing PRO surveys. Studies evaluating PROs administered by multimedia platforms could help researchers and clinicians plan the best strategies for assessing health-related quality of life in TBI caregivers.

Assessment of Diastolic Function Using Ultrasound Elastography.

Shear wave elasticity imaging (SWEI) is a novel ultrasound elastography technique for assessing tissue stiffness. In this study, we investigate the potential of SWEI for providing diastolic functional assessment. In 11 isolated rabbit hearts, pressure-volume (PV) measurements were recorded simultaneously with SWEI recordings from the left ventricle free wall before and after induction of global ischemia. PV-based end diastolic stiffness increased by 100% after ischemia (p <0.05), and SWEI stiffness showed an increase of 103% (p <0.05). The relaxation time constant (τ) before and after ischemia derived from pressure and SWEI curves showed increases of 79% and 76%, respectively (p <0.05). A linear regression between pressure-derived and SWEI-based (τ) showed a slope of 1.164 with R2 = 0.80, indicating the near equivalence of the two assessments. SWEI can be used to derive (τ) values and myocardial end diastolic stiffness. In global conditions, these measurements are consistent with PV measurements of diastolic function.

Quantifying Myocardial Contractility Changes Using Ultrasound-Based Shear Wave Elastography.

BACKGROUND: Myocardial contractility, a significant determinant of cardiac function, is valuable for diagnosis and evaluation of treatment in cardiovascular disorders including heart failure. Shear wave elasticity imaging (SWEI) is a newly developed ultrasound-based elastographic technique that can directly assess the stiffness of cardiac tissue. The aim of this study was to verify the ability of this technique to quantify contractility changes in the myocardium. METHODS: In 12 isolated rabbit hearts, SWEI measurements were made of systolic stiffness at five different coronary perfusion pressures from 0 to 92 mm Hg. The changes in coronary perfusion were used to induce acute stepwise reversible changes in cardiac contractility via the Gregg effect. The Gregg effect is the dependency of contractility on coronary perfusion. In four of the hearts, the measurements were repeated after delivery of gadolinium, which is known to block the Gregg effect. RESULTS: Systolic stiffness measured by SWEI changed linearly with coronary perfusion pressure, with a slope of 0.27 kPa/mm Hg (mean of 95% CI, R2 = 0.73). As expected, the change in contractility due to the Gregg effect was blocked by gadolinium, with a significant reduction of the slope to 0.08 kPa/mm Hg. CONCLUSIONS: SWEI measurements of systolic stiffness provide an index of contractility in the unloaded isolated rabbit heart. Although this study was done under ideal imaging conditions and with nonphysiologic loading conditions, it reinforces the concept that this ultrasound technique has the potential to provide a direct and noninvasive index of cardiac contractility.