Effects and mechanism of the HECT study (hybrid exercise-cognitive trainings) in mild ischemic stroke with cognitive decline: fMRI for brain plasticity, biomarker and behavioral analysis

Occupational therapy for cognitive impairment in stroke patients

BACKGROUND

Cognitive impairment is a frequent consequence of stroke and can impact on a person's ability to perform everyday activities. Occupational therapists use a range of interventions when working with people who have cognitive impairment poststroke. This is an update of a Cochrane Review published in 2010.

OBJECTIVES

To assess the impact of occupational therapy on activities of daily living (ADL), both basic and instrumental, global cognitive function, and specific cognitive abilities in people who have cognitive impairment following a stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE, Embase, four other databases (all last searched September 2020), trial registries, and reference lists.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials that evaluated an intervention for adults with clinically defined stroke and confirmed cognitive impairment. The intervention needed either to be provided by an occupational therapist or considered within the scope of occupational therapy practice as defined in the review. We excluded studies focusing on apraxia or perceptual impairments or virtual reality interventions as these are covered by other Cochrane Reviews. The primary outcome was basic activities of daily living (BADL) such as dressing, feeding, and bathing. Secondary outcomes were instrumental ADL (IADL) (e.g. shopping and meal preparation), community integration and participation, global cognitive function and specific cognitive abilities (including attention, memory, executive function, or a combination of these), and subdomains of these abilities. We included both observed and self-reported outcome measures.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies that met the inclusion criteria, extracted data, and assessed the certainty of the evidence. A third review author moderated disagreements if consensus was not reached. We contacted trial authors for additional information and data, where available. We assessed the certainty of key outcomes using GRADE.  MAIN RESULTS: We included 24 trials from 11 countries involving 1142 (analysed) participants (two weeks to eight years since stroke onset). This update includes 23 new trials in addition to the one study included in the previous version. Most were parallel randomised controlled trials except for one cross-over trial and one with a two-by-two factorial design. Most studies had sample sizes under 50 participants. Twenty studies involved a remediation approach to cognitive rehabilitation, particularly using computer-based interventions. The other four involved a compensatory and adaptive approach. The length of interventions ranged from 10 days to 18 weeks, with a mean total length of 19 hours. Control groups mostly received usual rehabilitation or occupational therapy care, with a few receiving an attention control that was comparable to usual care; two had no intervention (i.e. a waiting list). Apart from high risk of performance bias for all but one of the studies, the risk of bias for other aspects was mostly low or unclear.  For the primary outcome of BADL, meta-analysis found a small effect on completion of the intervention with a mean difference (MD) of 2.26 on the Functional Independence Measure (FIM) (95% confidence interval (CI) 0.17 to 4.22; P = 0.03, I2 = 0%; 6 studies, 336 participants; low-certainty evidence). Therefore, on average, BADL improved by 2.26 points on the FIM that ranges from 18 (total assist) to 126 (complete independence). On follow-up, there was insufficient evidence of an effect at three months (MD 10.00, 95% CI -0.54 to 20.55; P = 0.06, I2 = 53%; 2 studies, 73 participants; low-certainty evidence), but evidence of an effect at six months (MD 11.38, 95% CI 1.62 to 21.14, I2 = 12%; 2 studies, 73 participants; low-certainty evidence). These differences are below 22 points which is the established minimal clinically important difference (MCID) for the FIM for people with stroke. For IADL, the evidence is very uncertain about an effect (standardised mean difference (SMD) 0.94, 95% CI 0.41 to 1.47; P = 0.0005, I2 = 98%; 2 studies, 88 participants). For community integration, we found insufficient evidence of an effect (SMD 0.09, 95% CI -0.35 to 0.54; P = 0.68, I2 = 0%; 2 studies, 78 participants). There was an improvement of clinical importance in global cognitive functional performance after the intervention (SMD 0.35, 95% CI 0.16 to 0.54; P = 0.0004, I2 = 0%; 9 studies, 432 participants; low-certainty evidence), equating to 1.63 points on the Montreal Cognitive Assessment (MoCA) (95% CI 0.75 to 2.52), which exceeds the anchor-based MCID of the MoCA for stroke rehabilitation patients of 1.22. We found some effect for attention overall (SMD -0.31, 95% CI -0.47 to -0.15; P = 0.0002, I2 = 20%; 13 studies, 620 participants; low-certainty evidence), equating to a difference of 17.31 seconds (95% CI 8.38 to 26.24), and for executive functional performance overall (SMD 0.49, 95% CI 0.31 to 0.66; P < 0.00001, I2 = 74%; 11 studies, 550 participants; very low-certainty evidence), equating to 1.41 points on the Frontal Assessment Battery (range: 0-18). Of the cognitive subdomains, we found evidence of effect of possible clinical importance, immediately after intervention, for sustained visual attention (moderate certainty) equating to 15.63 seconds, for working memory (low certainty) equating to 59.9 seconds, and thinking flexibly (low certainty), compared to control.

AUTHORS' CONCLUSIONS

The effectiveness of occupational therapy for cognitive impairment poststroke remains unclear. Occupational therapy may result in little to no clinical difference in BADL immediately after intervention and at three and six months' follow-up. Occupational therapy may slightly improve global cognitive performance of a clinically important difference immediately after intervention, likely improves sustained visual attention slightly, and may slightly increase working memory and flexible thinking after intervention. There is evidence of low or very low certainty or insufficient evidence for effect on other cognitive domains, IADL, and community integration and participation.  Given the low certainty of much of the evidence in our review, more research is needed to support or refute the effectiveness of occupational therapy for cognitive impairment after stroke. Future trials need improved methodology to address issues including risk of bias and to better report the outcome measures and interventions used.

The Effect of 2 Different Dual-Task Balance Training Methods on Balance and Gait in Older Adults: A Randomized Controlled Trial

OBJECTIVE

The purpose of this study was to compare the effects of integrated and consecutive cognitive dual-task balance training in older adults on balance, fear of falling, and gait performance.

METHODS

Fifty-eight participants (age >65 years) were randomly assigned to an integrated dual-task training group (IDTT) (n = 29) and consecutive dual-task training group (CDTT) (n = 29). Balance exercises and cognitive tasks were performed simultaneously by the IDTT group and consecutively by the CDTT group for 8 weeks. Balance was assessed using the Berg Balance Scale as a primary outcome measure and the Timed "Up & Go" Test (TUG) (standard-cognitive), fear of falling was assessed using the Tinetti Falls Efficacy Scale, and gait speed was assessed using the 10-Meter Walk Test (10MWT) (under single-task and dual-task conditions). All tests were performed before and after the training.

RESULTS

There was no difference in group-time interaction in the Berg Balance Scale, TUG-standard, 10MWT-single task, and 10MWT-dual task tests. Group-time interaction was different in the TUG-cognitive and Tinetti Falls Efficacy Scale scores. Also, the effect of time was significantly different in all scales except for the 10MWT-single task in both groups.

CONCLUSION

At the end of the 8-week training period, the impact of integrated and consecutive dual-task balance training on balance and gait performance in older adults was not statistically significantly different. This study suggests that consecutive dual-task balance training can be used as an alternative method to increase balance performance and gait speed in older adults who cannot perform integrated dual-task activities.

IMPACT

There were no significant differences between the effects of the 2 dual-task training methods on balance and gait speed, suggesting that the consecutive dual-task balance training method can be used to improve the balance and gait of older adults. CDTT can be performed safely and considered as an alternative method for use in many rehabilitation training programs with older adults who cannot perform simultaneous activities.

Bicarbonate supplementation via lactate efflux improves anaerobic and cognitive performance in elite combat sport athletes

The aim of this study was the assessment of sodium bicarbonate supplementation (NaHCO₃^-) on anaerobic and cognitive performance, assuming ergogenic effect of HCO₃ by improving buffering capacity and greater lactate efflux, which may have indirect effect on circulating neurotrophin level (e.g BDNF, IGF-1) and memory. Sixteen well-trained judo athletes completed a randomized trial of either a NaHCO₃^- (EG) (5000 mg x 2/day/90 min before training)or placebo for 21 days (CG). Before and after treatment, athletes completed double Wingate test (Wt) protocol following which they performed perceived Working Memory test (pWM). Results suggested significant increase in Upper Limb Total Work (with p = 0.011), Mean Power (with p = 0.001), post exercise LA concentration (from 15.51 mmol/L to 18.10 mmol/L with p = 0.01) and HCO3_rest concentrations (from 27.37 mmol/l to 28.91 mmol/l with p = 0.001), when compared to baseline values in EG. The analysis showed statistically significant increase in values for IGF-1 (with p = 0.001) and decrease for cortisol and BDNF (with p = 0.001) in EG and CG, when pre and post exercise values were compared. We also revealed statistically significant decrease in values for display time after ingestion of HCO₃ between pre and post exercise (with p = 0.002) In conclusion, the lack of a substantial relationship between exerkines (IGF-1, BDNF) and memory in the present study might suggest that exercise induced lactate levels is dominant mechanism improving working memory in well-train athletes.

Rehabilitation training inhibits neuronal apoptosis by down-regulation of TLR4/MyD88 signaling pathway in mice with cerebral ischemic stroke

OBJECTIVE

To investigate the role of rehabilitation training and TLR4/MyD88 signaling pathway on neuronal apoptosis in mice with cerebral ischemic stroke.

METHODS

Mice were randomized into six groups, which were normal group (healthy mice, n=20), control group (sham surgery, n=20), model group (middle cerebral artery occlusion (MCAO) model, n=20), training (MCAO model, continuous rehabilitation training for 4 weeks, n=20), TAK-242 group (MCAO model, TL R4 inhibitor TAK-242, n=20), and TAK-242 + Training group (MCAO model, TLR4 inhibitor TAK-242 + rehabilitation training, n=20).

RESULTS

Neurobehavioral assessment was performed, and cerebral infarction area of mice was detected by triphenyl tetrazolium chloride staining. Compared with the normal group, no significant differences in all indicators were found in the control group (all P>0.05), while the other groups had higher neurological function scores, cerebral infarction area, neuronal apoptosis rate, increased expressions of TLR4, MyD88, Bax, NF-κB, TNF-α, Caspase-3, IL-1βA and decreased mRNA and protein expressions of Bcl-2 (all P<0.05).

CONCLUSION

Rehabilitation training can effectively reduce the apoptosis of hippocampal neurons in mice with ischemic stroke by inhibiting the TLR4/MyD88 signaling pathway.

Effects of Combined Interventions with Aerobic Physical Exercise and Cognitive Training on Cognitive Function in Stroke Patients: A Systematic Review

(1) Background: Stroke is a major cause of permanent disability in multiple functions, including the cognitive domain. Since both cognitive training and aerobic physical exercise may exert positive effects on cognition after stroke, one may expect synergistic benefits when combining both interventions. (2) Methods: We carried out a systematic search of studies testing, in adult stroke patients, whether structured aerobic exercise combined with cognitive training led to higher cognitive benefits than either of these interventions when applied singly, or than interventions not including aerobic exercise or cognitive training. (3) Results: Five fair-quality randomized controlled trials fulfilled the search criteria. Exercise intensity was moderate-vigorous and cognitive training was mainly computer-based. The studies were heterogeneous regarding the cognitive tests used, and for this reason, a meta-analysis was not performed. Only three studies included follow-up assessment. The combined intervention was associated with pre-post improvement in at least one cognitive test in all the studies, and with higher positive effects compared to other conditions (although statistical significance was not always reached) in four studies. (4) Conclusions: Further trials including a long-term follow-up and comprehensive neuropsychological testing should be undertaken to determine whether combined aerobic exercise and cognitive training leads to additive cognitive benefits after stroke.