Turning Over the Hourglass

Cognitive function, quality of life, and aging: relationships in individuals with and without spinal cord injury

Background: Correlations between aging, cognitive impairment and poor quality of life (QOL) have been observed for many patient populations.Objective: The purpose of this study was to examine these correlations in individuals with and without spinal cord injury (SCI).Methods: 23 individuals with complete SCI and 20 individuals without SCI ("NON") underwent assessment of cognitive function via the NIH Toolbox for Neurological and Behavioral Function. Participants self-rated QOL via global and symptom/domain-specific measures.Results: SCI rated global QOL to be lower than NON for the EQ-5D QALY (p < .001), but not the EQ-5D VAS, which imposes no penalty for wheeled mobility. Low QOL clustered mainly in domains pertaining to physical function/symptoms. Participants with SCI reported high QOL for positive affect/well-being and resilience. Cognitive function in SCI did not differ from NON. However, strong correlations between age and cognition observed in NON (all R² > 0.532) were absent in SCI. Significant correlations between cognition and QOL were prevalent for NON but not for SCI.Conclusions: Dissociation of age, cognition and QOL occurred with SCI. Divergence between EQ-5D QALY and VAS suggests that individuals with SCI may recalibrate personal assessments of QOL in ways that minimize the importance of mobility impairment.

Motor demands of cognitive testing may artificially reduce executive function scores in individuals with spinal cord injury

Objective: To determine whether the motor demands of cognitive tests contribute to differences in cognitive function scores in participants with and without spinal cord injury (SCI).Design: Cohort study.Setting: Rehabilitation research laboratory.Participants: 68 individuals without SCI ("NON") and 22 individuals with motor complete SCI ("SCI").Interventions: None.Outcome Measures: NIH Toolbox cognitive assessments, including two with motor demands and reaction-time based scoring (Dimensional Change Card Sort (DCCS), Flanker Inhibitory Control and Attention (Flanker) and two without timed scoring (List Sorting Working Memory (List Sorting), Picture Sequence Memory Test (Picture Sequence). Tests were administered with and without the assistance of a proctor on two randomly-determined days (>24 hr interval). For DCCS and Flanker, the motor-task score offset was estimated as the difference between the proctored and non-proctored scores.Results: For demographically-corrected data, proctoring reduced DCCS and Flanker scores (P < 0.001) but mitigated apparent differences between SCI and NON (all P > 0.403). SCI and NON did not differ for List Sorting (P > 0.072) but did differ significantly for Picture Sequence (P < 0.001). Significant practice effects existed for memory-based tests (List Sorting and Picture Sequence); all P < 0.015, effect size>0.645.Conclusions: DCCS and Flanker scores for individuals with SCI may be artificially reduced consequent to secondary motor demands of the tests. Proctoring and computation of a motor-response score offset enables comparisons to be made between individuals with SCI and a Non-SCI control cohort; however, further work is needed to determine whether offset-adjusted scores can be compared to standardized normative values.

Modified Outpatient Physical Therapy Improvement in Movement Assessment Log (mOPTIMAL): A Responsive and Reliable Tool for Patients with Non-Operative Shoulder Pain

BACKGROUND

Medicare regulations require that physical therapists report functional limitations and severity modifiers utilizing a claims-based data collection tool. The Modified Outpatient Physical Therapy Improvement in Movement Assessment Log (mOPTIMAL) captures key constructs about patient confidence and difficulty but has not been evaluated for responsiveness/ reliability during a routine clinical encounter with patients who have shoulder pathology. The purposes of this retrospective study are to 1) explore if mOPTIMAL changes after a single session with a physical therapist, and 2) determine if the tool is reliable among people with non-operative shoulder pain.

METHODS

We included 106 individuals (58% female; mean age 45.8; range: 18-94 yrs.) with "non-operative" shoulder pathology who were seen in outpatient physical therapy from 2011 to 2012. Subjects completed a mOPTIMAL survey and a pain scale before and immediately after the initial physical therapy visit. The mOPTIMAL is a patient-centered instrument that assesses how much "Difficulty" and "Confidence" a client has in performing a battery of functional tasks. T-tests, Cronbach's Alpha, and Intra-class Correlations were used to assess responsiveness, internal consistency, and reliability, respectively.

RESULTS

After a single visit, participants reported improved Confidence with sleeping, dressing/ bathing, throwing, carrying, and lifting (adjusted for ceiling effects; p<0.002) but no change in pain. Cronbach's Alpha and Intra-class Correlations were excellent (0.821-0.923; 0.967, respectively).

CONCLUSIONS

mOPTIMAL is a reliable and responsive tool with excellent internal consistency. This observational study revealed that patient Confidence may change independent of Pain after a single physical therapy visit. Taken together, the mOPTIMAL appears to be an excellent tool to report severity modifiers in compliance with Medicare regulations.Level of Evidence: IV.

Impact of short- and long-term electrically induced muscle exercise on gene signaling pathways, gene expression, and PGC1a methylation in men with spinal cord injury

Exercise attenuates the development of chronic noncommunicable diseases (NCDs). Gene signaling pathway analysis offers an opportunity to discover if electrically induced muscle exercise regulates key pathways among people living with spinal cord injury (SCI). We examined short-term and long-term durations of electrically induced skeletal muscle exercise on complex gene signaling pathways, specific gene regulation, and epigenetic tagging of PGC1a, a major transcription factor in skeletal muscle of men with SCI. After short- or long-term electrically induced exercise training, participants underwent biopsies of the trained and untrained muscles. RNA was hybridized to an exon microarray and analyzed by a gene set enrichment analysis. We discovered that long-term exercise training regulated the Reactome gene sets for metabolism (38 gene sets), cell cycle (36 gene sets), disease (27 gene sets), gene expression and transcription (22 gene sets), organelle biogenesis (4 gene sets), cellular response to stimuli (8 gene sets), immune system (8 gene sets), vesicle-mediated transport (4 gene sets), and transport of small molecules (3 gene sets). Specific gene expression included: oxidative catabolism of glucose including PDHB (P < 0.001), PDHX (P < 0.001), MPC1 (P < 0.009), and MPC2 (P < 0.007); Oxidative phosphorylation genes including SDHA (P < 0.006), SDHB (P < 0.001), NDUFB1 (P < 0.002), NDUFA2 (P < 0.001); transcription genes including PGC1α (P < 0.030) and PRKAB2 (P < 0.011); hypertrophy gene MSTN (P < 0.001); and the myokine generating FNDC5 gene (P < 0.008). Long-term electrically induced exercise demethylated the major transcription factor PGC1a. Taken together, these findings support that long-term electrically induced muscle activity regulates key pathways associated with muscle health and systemic metabolism.

Precision Physical Therapy: Exercise, the Epigenome, and the Heritability of Environmentally Modified Traits

One of the newest frontiers of physical therapy is the field of epigenetics, which examines how pervasive environmental factors such as exercise regulate the expression of genes. The epigenome may be one of the most powerful systems through which exercise exerts its beneficial effects on health and longevity. Large epidemiology studies show that individuals who regularly exercise demonstrate a lower "epigenetic age," experience fewer metabolic diseases, and enjoy greater longevity. However, the dose, mode, intensity, and duration of exercise required to achieve a healthy epigenetic profile is unknown. As experts in exercise prescription, physical therapists are ideally suited to contribute to the discovery of this dose-response relationship. This perspective makes a case for the genesis of "precision physical therapy," which capitalizes on epigenetic discoveries to optimize exercise-based interventions. Summarized here is the emerging body of knowledge supporting epigenetic adaptations to exercise in humans, including the intriguing possibility that these environmentally modified traits could be passed down to offspring. In the future, it is likely that epigenetic data will enhance our understanding of individual disease risk and individual response to prescribed exercise. The profession of physical therapy must be alert to new epigenetic knowledge that can enhance the specificity and efficacy of movement-based treatments.