Physical Exercise As Stabilizer For Alzheimer'S Disease Cognitive Decline: Current Status

Does Therapeutic Exercise Support Improvement in Cognitive Function and Instrumental Activities of Daily Living in Patients with Mild Alzheimer's Disease? A Randomized Controlled Trial

This randomized controlled trial aims to investigate the effect of 12 weeks of therapeutic exercise on cognitive function and daily activities in patients with mild Alzheimer's disease (AD). A total of 171 patients with mild AD from the Amarousion Day Care Center of the Alzheimer Society of Athens and the Athens General Hospital "G. Gennimatas" were randomly divided into three groups. Group A (aerobic and resistance exercise, n = 57), group B (resistance exercise, n = 57), and group C (control group, n = 57). Group A followed a weekly program consisting of 5 days with 30 min walking and 3 days with resistance exercises for about 45 min. Group B followed only a resistance exercise program, the same as group A. Group C did not participate in any exercise program. After the intervention, cognitive function was assessed with the Cognitive Examination-Revised (ACE-R), Trail Making Test A-B (TMT A-B), and Digit Span Test Forward and Backward (DST F-B) and daily activities with the instrumental activities of daily living scale (IADLs). A significant intervention effect was observed for all outcome measures (global cognitive function and instrumental activities of daily living). ANCOVA Bonferroni corrected post hoc tests revealed that the aerobic and resistance group improved compared to the control group on all measurement scales. The resistance group also showed an improvement compared to the control group. No significant effects were found between the aerobic and resistance group and the resistance group in any of the outcome measures.

Analysis of Functional and Cognitive Impairment in Institutionalized Individuals with Movement Disorders

BACKGROUND

Many neurological disorders lead to institutionalization and can be accompanied in their advanced stages by functional impairment, and progressive loss of mobility, and cognitive alterations.

OBJECTIVE

We analyzed the relationship between functional impairment and cognitive performance and its related subdomains in individuals with Parkinson's disease, Alzheimer's disease accompanied by motor dysfunction, and with other neurological disorders characterized by both motor and cognitive problems.

METHODS

All participants lived in nursing homes (Valencia, Spain) and underwent cognitive evaluation with the Mini-Mental State Examination; functional assessment of independence in activities of daily living using the Barthel score and Katz index; and assessment of mobility with the elderly mobility scale.

RESULTS

The mean age of the subjects was 82.8 ± 0.6 years, 47% of the sample included individuals with Parkinson's disease, and 48 % of the sample presented severe cognitive impairment. Direct significant relationships were found between the level of cognitive impairment and functional capacity (p < 0.01) and mobility (p < 0.05). Among the different domains, memory impairment was not associated with altered activities of daily living or mobility. The functional impairment and the risk of severe cognitive impairment were significantly (p<0.05) higher in female compared to male patients. Among comorbidities, overweight/obesity and diabetes were significantly (p < 0.05) associated with poor cognitive performance in those individuals with mild/moderate cognitive impairment.

CONCLUSION

In institutionalized individuals with movement disorders there is an association between functional and cognitive impairment. Reduction of over-weight and proper control of diabetes may represent novel targets for improving cognitive function at such early stages.

Enhancement of hypothalamic-pituitary activity in male athletes: evidence of a novel hormonal mechanism of physical conditioning

BACKGROUND

Exercise is known to induce multiple beneficial conditioning processes. Conversely, although exercise may generate several hormonal effects, an intrinsic hormonal conditioning process has not been reported. In the Endocrine and Metabolic Responses on Overtraining Syndrome (EROS) study, we observed inherent and independent conditioning processes of the hypothalamic-pituitary axes in athletes. Our objective is to describe the theory of the novel hormonal conditioning mechanism using the findings from the EROS study.

METHODS

In this cross-sectional study, we selected 25 healthy athletes (ATL) and 12 non-physically active healthy controls (NPAC), 18-50 years old, males, with BMI 20-30 kg/m², with similar baseline characteristics, who underwent gold-standard exercise-independent tests: cosyntropin stimulation test (CST) and insulin tolerance test (ITT), to evaluate cortisol response to CST, and ACTH, cortisol, GH, and prolactin responses to an ITT.

RESULTS

Responses to ITT were significantly earlier and higher in ATL than NPAC for cortisol [Mean ± SD: 21.7 ± 3.1 vs 16.9 ± 4.1 μg/dL; p < 0.001], GH [Median (95% CI): 12.73 (1.1-38.1) vs 4.80 (0.33-27.36) μg/L; p = 0.015], and prolactin [24.3 (10.5-67.45) vs 10.50 (6.21-43.44) ng/mL; p = 0.002]. Cortisol response to CST was similar between ATL and NPAC. During ITT, cortisol, GH, and ACTH mean increase in ATL were 52.2, 265.2, and 18.6% higher than NPAC, respectively. Prolactin response was absent in NPAC, while present in ATL.

CONCLUSIONS

We found sufficient evidence to propose the existence of a diffuse enhancement of the hypothalamic-pituitary activity in athletes, not restricted to any axis, showing an intrinsic and independent process of "hormonal conditioning" in athletes, similar to those observed in the cardiovascular and neuromuscular systems. This novel conditioning process may be the missing link for understanding the improved responses observed in athletes to harmful situations, traumas, infections, inflammations, and psychiatric conditions.

Effects of physical activity and exercise on the cognitive function of patients with Alzheimer disease: a meta-analysis

BACKGROUND

Alzheimer's disease (AD), as the most common cause of dementia, brings huge economic burden for patients and social health care systems, which motivates researchers to study multiple protective factors, among which physical activity and exercise have been proven to be both effective and economically feasible.

METHODS

A systematic literature search was performed for eligible studies published up to November 1st 2018 on three international databases (PubMed, Cochrane Library, and Embase) and two Chinese databases (Wanfang Data, China National Knowledge Infrastructure). All analyses were conducted using Stata 14.0. Due to heterogeneity between studies, a random-effects model was used for this meta-analysis. Meta-analysis was used to explore if physical activity and exercise can exert positive effects on cognition of elderly with AD and subgroup analyses were conducted to find out if there are dose-response effects.

RESULTS

A total of 13 randomized controlled trials were included with a sample size of 673 subjects diagnosed with AD. Intervention groups showed a statistically significant improvement in cognition of included subjects measured by the MMSE score (SMD = 1.12 CI:0.66~1.59) compared to the control groups. Subgroup analyses showed different amounts of physical activity and exercise can generate different effects.

CONCLUSIONS

As one of few meta-analyses comparing different quantities of physical activity and exercise interventions for AD in details, our study suggests that physical activity and exercise can improve cognition of older adults with AD. While the concomitant effects on cognition functions of high frequency interventions was not greater than that of low frequency interventions, the threshold remains to be settled. However, more RCTs with rigorous study design are needed to support our findings.

Relationship between mobility and cognitive impairment in patients with Alzheimer's disease

OBJECTIVE

Alzheimer's disease (AD) is usually accompanied by impairments to mobility, performance of the basic activities of daily life (ADL), and progressive cognitive decline. We analyzed the relationship between cognitive performance and related cognitive subdomains and mobility.

PATIENTS AND METHODS

All AD patients of the recruited individuals were living in nursing homes; they underwent a blood analysis, cognitive examination by using the Mini-Mental State Examination, functional evaluation of independence in the ADLs with Barthel score and Katz index, and mobility assessment with the elderly mobility scale.

RESULTS

The mean sample age was 84 years and majority were women; more than 60% of the participants had severe cognitive impairment. Statistically significant relationships were found between the severity of cognitive impairment and functional capacity (p <  0.01) and their degree of mobility (p <  0.05). Among the different domains, memory impairment was not associated with impaired mobility or ability to perform the ADLs. Women had lower scores in the ADL and mobility assessments (p <  0.05) and an increased ratio of severe cognitive impairment (OR = 3.03 95% CI: [1.30, -7.05]) compared to men. Being overweight or obese and high blood levels of HDL cholesterol were directly (p <  0.05) and inversely (p <  0.01) associated with poor cognitive performance in individuals with mild to moderate cognitive dysfunction, respectively.

CONCLUSIONS

This study shows that better functional capacity and mobility are generally, but not exclusively, correlated with better cognitive function, depending on the severity of cognitive impairment. In contrast, lipid profile alterations might play a role in cognitive deficits in individuals with mild to moderate cognitive impairment who are overweight. Further longitudinal studies will be required to explore this possibility.

Inter-correlations Among Clinical, Metabolic, and Biochemical Parameters and Their Predictive Value in Healthy and Overtrained Male Athletes: The EROS-CORRELATIONS Study

Objectives: The Endocrine and Metabolic Responses on Overtraining Syndrome (EROS) study identified multiple hormonal and metabolic conditioning processes in athletes, and underlying mechanisms and biomarkers of overtraining syndrome (OTS). The present study's objective was to reveal independent predictors and linear correlations among the parameters evaluated in the EROS study to predict clinical, metabolic, and biochemical behaviors in healthy and OTS-affected male athletes. Methods: We used multivariate linear regression and linear correlation to analyze possible combinations of the 38 parameters evaluated in the EROS study that revealed significant differences between healthy and OTS-affected athletes. Results: The testosterone-to-estradiol (T:E) ratio predicted the measured-to-predicted basal metabolic rate (BMR) ratio; the T:E ratio and total testosterone level were inversely predicted by fat mass and estradiol was not predicted by any of the non-modifiable parameters. Early and late growth hormone, cortisol, and prolactin responses to an insulin tolerance test (ITT) were strongly correlated. Hormonal responses to the ITT were positively correlated with fat oxidation, predicted-to-measured BMR ratio, muscle mass, and vigor, and inversely correlated with fat mass and fatigue. Salivary cortisol 30 min after awakening and the T:E ratio were inversely correlated with fatigue. Tension was inversely correlated with libido and directly correlated with body fat. The predicted-to-measured BMR ratio was correlated with muscle mass and body water, while fat oxidation was directly correlated with muscle mass and inversely correlated with fat mass. Muscle mass was directly correlated with body water, and extracellular water was directly correlated with body fat and inversely correlated with body water and muscle mass. Conclusions: Hypothalamic-pituitary responses to stimulation were diffuse and indistinguishable between the different axes. A late hormonal response to stimulation, increased cortisol after awakening, and the T:E ratio were correlated with vigor and fatigue. The T:E ratio was also correlated with body metabolism and composition, testosterone was predicted by fat mass, and estradiol predicted anger. Hydration status was inversely correlated with edema, and inter-correlations were found among fat oxidation, hydration, and body fat.