Participation and Life Satisfaction in Aged People with Spinal Cord Injury: Does Age at Onset Make a Difference?

Background:

Few studies have reported on outcomes in samples of elderly people with SCI and the impact of the age at onset of SCI is unclear.

Objective:

To study levels of participation and life satisfaction in individuals with SCI aged 65 years or older and to analyze differences in participation and life satisfaction scores between individuals injured before or after 50 years of age.

Methods:

This cross-sectional survey included 128 individuals with SCI who were at least 65 years old. Age at onset was dichotomized as <50 or ≥50 years of age. Participation was measured with the Frequency scale of the Utrecht Scale for Evaluation-Participation, and life satisfaction was measured with 5 items of the World Health Organization Quality of Life abbreviated form.

Results:

Participants who were injured before 50 years of age showed similar levels of functional status and numbers of secondary health conditions but higher participation and life satisfaction scores compared to participants injured at older age. In the multiple regression analysis of participation, lower current age, higher education, and having paraplegia were significant independent determinants of increased participation (explained variance, 25.7%). In the regression analysis of life satisfaction, lower age at onset and higher education were significant independent determinants of higher life satisfaction (explained variance, 15.3%).

Conclusion:

Lower age at onset was associated with better participation and life satisfaction. This study did not reveal indications for worsening participation or life satisfaction due to an accelerated aging effect in this sample of persons with SCI.Key words: aged, aging, quality of life, rehabilitation outcome, spinal cord injuriesAging in the population of individuals with spinal cord injury (SCI) has 2 aspects: the average age at onset of SCI is increasing and people with SCI live on average longer than half a century ago. Age at onset of traumatic SCI has risen from 28.7 years in the 1970s to 40 years in the United States during the 2005-2009 period.¹ In other countries, a bimodal distribution of age at onset of traumatic SCI has emerged in recent years.² In the Netherlands, the median age at first admission to the acute hospital after traumatic SCI has increased to 62 years in 2010.³ People who are older at injury are more often victims of falls and have nontraumatic, incomplete, and cervical SCI more often than individuals who are injured at a younger age.³-⁵ They are more vulnerable than younger people and are at greater risk of death shortly after the onset of SCI.⁶ If they survive the acute phase, they are less often referred to specialized rehabilitation hospitals.³ If referred to a specialized center, elderly people with SCI may gain a similar rate of functional improvement⁷; but because older patients generally have lower functional scores at admission, they also show worse rehabilitation outcomes compared to people who are injured at a younger age.^4,8–10The life expectancy of the population with SCI has grown over the last 50 to 60 years.¹¹ Many people with a new SCI can expect to live another 30 to 40 years or more. However, this life expectancy has not grown in recent decades and is still clearly below that of the general population.¹¹ People with SCI are at risk of “accelerated aging” due to an inactive lifestyle and a greater risk of obesity, chronic inflammation, pressure ulcers, and pulmonary infections.^1,12Participation and quality of life in aged persons with SCI are influenced by a complex interaction of many factors associated with current chronologic age, age at injury, duration of injury, and age cohort effects. It has been suggested that increasing age and being of older age at onset of SCI are independently associated with worse outcomes and that longer time after SCI is associated with better adjustment, whereas the impact of age cohort effects on adjustment is unknown.^1,13–15 However, research into the impact of these health-related changes on participation and life satisfaction of aged people living with SCI is sparse, and associations with aging are often studied in samples that are well below retirement age.¹⁵Only 2 longitudinal projects in aging people with SCI are available. Krause and Bozard¹⁶ described 35-year longitudinal data of 64 individuals with SCI (mean age, 61.5 years; mean time since SCI, 41.4 years). The participants rated their overall adjustment significantly higher at follow-up than they did at the first assessment 35 years before (8.4 and 7.6 on a 0–10 scale, respectively). The participants, however, showed decreases in satisfaction with social life and participation indicators (visits with others, outings).¹⁶ Charlifue and Gerhart¹⁷ found in a large sample of people with long-standing SCI (mean age, 59 years; time since onset of SCI, 36 years at follow-up) a small but significant decline in community reintegration over a period of 10 years. Life satisfaction, however, remained stable over this time period.¹⁷It is still unclear how people aging with SCI differ from people who acquire SCI in later life.¹⁸ Given the same age, the accelerated aging hypothesis predicts that people injured at a younger age will be worse off. However, the reverse – higher age at injury is an independent predictor of worse functional outcomes – has also been shown.¹⁰ We therefore used data from earlier research with the following objectives: (a) to describe the levels of participation and life satisfaction in individuals with SCI aged 65 years or older, and (b) to analyze differences in participation and life satisfaction between individuals injured before 50 years of age or at or after 50 years of age.     

Time and Effort Required by Persons with Spinal Cord Injury to Learn to Use a Powered Exoskeleton for Assisted Walking

Background:

Powered exoskeletons have been demonstrated as being safe for persons with spinal cord injury (SCI), but little is known about how users learn to manage these devices.

Objective:

To quantify the time and effort required by persons with SCI to learn to use an exoskeleton for assisted walking.

Methods:

A convenience sample was enrolled to learn to use the first-generation Ekso powered exoskeleton to walk. Participants were given up to 24 weekly sessions of instruction. Data were collected on assistance level, walking distance and speed, heart rate, perceived exertion, and adverse events. Time and effort was quantified by the number of sessions required for participants to stand up, walk for 30 minutes, and sit down, initially with minimal and subsequently with contact guard assistance.

Results:

Of 22 enrolled participants, 9 screen-failed, and 7 had complete data. All of these 7 were men; 2 had tetraplegia and 5 had motor-complete injuries. Of these, 5 participants could stand, walk, and sit with contact guard or close supervision assistance, and 2 required minimal to moderate assistance. Walk times ranged from 28 to 94 minutes with average speeds ranging from 0.11 to 0.21 m/s. For all participants, heart rate changes and reported perceived exertion were consistent with light to moderate exercise.

Conclusion:

This study provides preliminary evidence that persons with neurological weakness due to SCI can learn to walk with little or no assistance and light to somewhat hard perceived exertion using a powered exoskeleton. Persons with different severities of injury, including those with motor complete C7 tetraplegia and motor incomplete C4 tetraplegia, may be able to learn to use this device.     

Multispecies blow fly myiasis combined with hypothermia in a man assumed to be dead

Parasitology Research - We describe the case of a man who was found with severe hypothermia and advanced myiasis involving five species of blow flies, which eventually led to a transtibial...     

A Dependable Massive Storage Service for Medical Imaging

We present the construction of Babel, a distributed storage system that meets stringent requirements on dependability, availability, and scalability. Together with Babel, we developed an application that uses our system to store medical images. Accordingly, we show the feasibility of our proposal to provide an alternative solution for massive scientific storage and describe the software architecture style that manages the DICOM images life cycle, utilizing Babel like a virtual local storage component for a picture archiving and communication system (PACS-Babel Interface). Furthermore, we describe the communication interface in the Unified Modeling Language (UML) and show how it can be extended to manage the hard work associated with data migration processes on PACS in case of updates or disaster recovery.     

Shared decision-making in older patients with colorectal or pancreatic cancer: Determinants of patients’ and observers’ perceptions

Objective

To identify determinants of older patients’ perceptions of involvement in decision-making on colorectal (CRC) or pancreatic cancer (PC) treatment, and to compare these with determinants of observers' perceptions.

Sustained cross‐presentation capacity of murine splenic dendritic cell subsets in vivo

An exclusive feature of dendritic cells (DCs) is their ability to cross‐present exogenous antigens in MHC class I molecules. We analyzed the fate of protein antigen in antigen presenting cell (APC) subsets after uptake of naturally formed antigen‐antibody complexes in vivo. We observed that murine splenic DC subsets were able to present antigen in vivo for at least a week. After ex vivo isolation of four APC subsets, the presence of antigen in the storage compartments was visualized by confocal microscopy. Although all APC subsets stored antigen for many days, their ability and kinetics in antigen presentation was remarkably different. CD8α⁺ DCs showed sustained MHC class I‐peptide specific CD8⁺ T‐cell activation for more than 4 days. CD8α^? DCs also presented antigenic peptides in MHC class I but presentation decreased after 48 h. In contrast, only the CD8α^? DCs were able to present antigen in MHC class II to specific CD4⁺ T cells. Plasmacytoid DCs and macrophages were unable to activate any of the two T‐cell types despite detectable antigen uptake. These results indicate that naturally occurring DC subsets have functional antigen storage capacity for prolonged T‐cell activation and have distinct roles in antigen presentation to specific T cells in vivo.     

Frequency selectivity without resonance in a fluid waveguide

This study analyzes a waveguide consisting of two parallel fluid-filled chambers connected by a narrow slit that is spanned by two coupled elastic beams. A stiffness gradient exists in the longitudinal direction. This simple linear system, which contains no lumped mass, is shown to act as a spectral analyzer. Fluid waves traveling in the waveguide exhibit a distinct amplitude peak at a longitudinal location that varies systematically with frequency. The peaking is not based on resonance, but entirely on wave dispersion. When entering its peak region, the wave undergoes a sharp deceleration associated with a transition in which two propagation modes exchange roles. It is proposed that this mode shape swapping underlies the frequency analysis of the mammalian cochlea.In this study I explore the following question: How can a waveguide act as a spectral analyzer which spatially separates the frequency components of a wideband input? This question has been debated since Bekesy''s observation of traveling waves in the mammalian inner ear (1), the cochlea. On their way from base to apex, these fluid waves exhibit an amplitude peak at a frequency-dependent place. The peaking underlies our ability to identify and separate sounds.The most common explanation of cochlear frequency selectivity invokes local resonances coupled to the traveling wave (2). This approach requires a form of mass loading of the cochlear partition in addition to the mass loading by the surrounding fluid. The amount of mass needed in such models has been criticized for being unrealistically large given the cochlear anatomy (3). Even when sidestepping these objections, it has proved difficult to formulate models that reproduce both the amplitude and phase data of sensitive cochleae. On their way to the amplitude peak, cochlear traveling waves accumulate only 1–2 cycles (4, 5). Resonance-based models that produce sharp amplitude peaking tend to systematically overestimate the phase accumulation (6, 7). The resonance point acts as a cutoff, and a hypothetical frictionless wave would accumulate an infinite number of cycles when approaching it (8). Although damping will temper this singular behavior, too much of it also spoils the amplitude peaking.In active cochlear models (9, 10) this problem is circumvented by postulating a limited region of mechanical amplification (“negative damping”) basal to the resonance point. This creates a sufficiently sharp amplitude peak at a more basal location (safely away from the singularity), while still allowing ordinary damping to temper the phase accumulation near the resonance point (7).The present study explores an alternative approach which rejects resonance as the mechanism producing the peaking. In this scenario the peaking of traveling waves is created by a form of wave dispersion that is characterized by a steep deceleration of the energy transport. The deceleration produces a densification (focusing) of the energy that creates the peaking. This approach was motivated by neural data revealing a steep deceleration of cochlear waves near their peak (5, 11). Rather than building an elaborate biophysical model, the aim was to find the simplest possible fluid waveguide exhibiting steep deceleration and peaking.