Association Between Muscular Strength and Cognition in People With Major Depression or Bipolar Disorder and Healthy Controls

Everyday function in schizophrenia: The impact of aerobic endurance and skeletal muscle strength

BACKGROUND

Patients with schizophrenia suffer from physical health conditions, culminating in reduced physical functioning with enormous costs for patients and society. Although aerobic endurance and skeletal muscle strength, typically reduced in this population, relate to cognition and function, no study has explored their respective contributions to performance of functional skills and everyday tasks.

METHODS

In a cross-sectional study, 48 outpatients (28/20 men/women; 35 ± 11(SD) years) with schizophrenia spectrum disorders (ICD-10; F20-25) were administered the UCSD Performance-based Skills Assessment-Brief (UPSA-B; functional skills), Specific Level of Functioning (SLOF; functional performance) and the Positive and Negative Syndrome (PANSS) scale. Peak oxygen uptake (V̇O2peak) was assessed along with leg press maximal muscle strength (1RM) and mechanical power.

RESULTS

UPSA-B performance was associated with V̇O2peak (r = 0.28,p < 0.05), accounting for 8 % (p < 0.05) of shared variance, but was unrelated to 1RM and mechanical power. The SLOF physical functioning domain was associated with V̇O2peak (r = 0.30,p < 0.05) and 1RM (r = 0.24,p < 0.05), while SLOF personal care (r = 0.27,p < 0.05) and activities (r = 0.30,p < 0.05) were related only to V̇O2peak. Hierarchical regression analyses revealed that while V̇O2peak and age combined to account for 20 % (p < 0.05) of the variance in physical functioning, the contribution of 1RM was eliminated after adjusting for age. V̇O2peak and negative symptoms combined predicted 24 % and 35 % of the variance in personal care and activities, respectively. UPSA-B scores did not add to the prediction of SLOF scores.

CONCLUSIONS

Although V̇O2peak and 1RM both relate to functional outcomes, the combination of V̇O2peak, age, and negative symptoms exert the greatest detrimental influence on functional performance beyond skills deficits.

Association between relative grip strength and depression among U.S. middle-aged and older adults: results from the NHANES database

Background

Mental health issues among middle-aged and older adults are gaining increasing attention. Recent studies have shown that relative grip strength is associated with cardiovascular diseases and various cancers, but its relationship with depression remains unclear.

Methods

This cross-sectional study included data from adults aged 50 years and older from the 2011-2014 National Health and Nutrition Examination Survey. Relative grip strength is calculated by dividing the maximum absolute grip strength of both hands by BMI. The Patient Health Questionnaire (PHQ-9) was used to evaluate the depressive outcome. Multivariate logistic regression was performed to assess the association between relative grip strength and depression.

Results

In this study, a total of 3,639 participants (≥50 years) with a mean age of 64.3 ± 9.3 years were enrolled, of whom 48.9% were male. Compared with individuals with lower relative handgrip strength in Q1 (≤1.64 kg/BMI), the adjusted OR values for relative handgrip strength and depression in Q2 (1.64-2.17 kg/BMI), Q3 (2.17-2.84 kg/BMI), and Q4 (≥2.84 kg/BMI) were 0.69 (95% CI: 0.51, 0.93, p = 0.016), 0.36 (95% CI: 0.24, 0.55, p < 0.001), and 0.32 (95% CI: 0.20, 0.51, p < 0.001), respectively. The relationship between relative grip strength and depression presented an L-shaped curve (nonlinear, p = 0.006), with an inflection point of roughly 2.98 kg/BMI. Among participants with relative grip strength < 2.98 kg/BMI, the OR of incident depression was 0.41 (95% CI: 0.30-0.55, p < 0.001).

Conclusion

Our findings indicated that relative grip strength was inversely associated with incident depression and demonstrated an L-shaped relationship among U.S. middle-aged and older adults. Relative grip strength could be the indicator for future screening of mental health.

The brain structure, inflammatory, and genetic mechanisms mediate the association between physical frailty and depression

Cross-sectional studies have demonstrated strong associations between physical frailty and depression. However, the evidence from prospective studies is limited. Here, we analyze data of 352,277 participants from UK Biobank with 12.25-year follow-up. Compared with non-frail individuals, pre-frail and frail individuals have increased risk for incident depression independent of many putative confounds. Altogether, pre-frail and frail individuals account for 20.58% and 13.16% of depression cases by population attributable fraction analyses. Higher risks are observed in males and individuals younger than 65 years than their counterparts. Mendelian randomization analyses support a potential causal effect of frailty on depression. Associations are also observed between inflammatory markers, brain volumes, and incident depression. Moreover, these regional brain volumes and three inflammatory markers-C-reactive protein, neutrophils, and leukocytes-significantly mediate associations between frailty and depression. Given the scarcity of curative treatment for depression and the high disease burden, identifying potential modifiable risk factors of depression, such as frailty, is needed.

Exploring the Association between Elevated Anxiety Symptoms and Low Skeletal Muscle Mass among Asymptomatic Adults: A Population-Based Study in Republic of Korea

Individuals with mental health problems are at higher risk of musculoskeletal diseases. However, the association between low muscle mass (LMM) and anxiety symptoms remains uninvestigated. This cross-sectional study enrolled 174,262 adults (73,833 women, 100,429 men), aged 18 to 89, who completed the anxiety scale and body composition analyses. Using bio-electrical impedance analysis, skeletal muscle mass index (SMI) was calculated based on appendicular skeletal muscle mass (ASM) (kg)/height (m2). LMM was defined as SMI < 7.0 kg/m2 in men and <5.4 kg/m2 in women. Anxiety symptoms were screened using the Clinical Useful Anxiety Outcome Scale (CUXOS) with cut-off scores of 20, 30, and 40. Multivariable logistic regression analyses were performed. LMM prevalence was 20.17% in women, 3.86% in men (p < 0.001). The prevalence of anxiety symptoms in LMM group decreased from mild (CUXOS > 20: women, 32.74%, men, 21.17%) to moderate (CUXOS > 30: 13.34%, 7.32%), to severe anxiety symptoms (CUXOS > 40: 4.00%, 1.73%). In multivariable-adjusted models, LMM was associated with mild (aOR (95% confidence interval)), women, 1.13 (1.08-1.17); men, 1.17 (1.08-1.27)), moderate (1.17 (1.11-1.24); 1.35 (1.19-1.53) and severe anxiety symptoms (1.18 (1.07-1.3), 1.36 (1.06-1.74)), demonstrating an increased risk of ORs with escalating anxiety severity. LMM was independently associated with a higher prevalence of anxiety symptoms.

Relative associations of behavioral and physiological risks for cardiometabolic disease with cognition in bipolar disorder during mid and later-life: findings from the UK biobank

BACKGROUND

Cardiometabolic disease risk factors are disproportionately prevalent in bipolar disorder (BD) and are associated with cognitive impairment. It is, however, unknown which health risk factors for cardiometabolic disease are relevant to cognition in BD. This study aimed to identify the cardiometabolic disease risk factors that are the most important correlates of cognitive impairment in BD; and to examine whether the nature of the relationships vary between mid and later life.

METHODS

Data from the UK Biobank were available for 966 participants with BD, aged between 40 and 69 years. Individual cardiometabolic disease risk factors were initially regressed onto a global cognition score in separate models for the following risk factor domains; (1) health risk behaviors (physical activity, sedentary behavior, smoking, and sleep) and (2) physiological risk factors, stratified into (2a) anthropometric and clinical risk (handgrip strength, body composition, and blood pressure), and (2b) cardiometabolic disease risk biomarkers (CRP, lipid profile, and HbA1c). A final combined multivariate regression model for global cognition was then fitted, including only the predictor variables that were significantly associated with cognition in the previous models.

RESULTS

In the final combined model, lower mentally active and higher passive sedentary behavior, higher levels of physical activity, inadequate sleep duration, higher systolic and lower diastolic blood pressure, and lower handgrip strength were associated with worse global cognition.

CONCLUSIONS

Health risk behaviors, as well as blood pressure and muscular strength, are associated with cognitive function in BD, whereas other traditional physiological cardiometabolic disease risk factors are not.

Higher handgrip strength is linked to higher salience ventral attention functional network segregation in older adults

Converging evidence suggests that handgrip strength is linked to cognition in older adults, and this may be subserved by shared age-related changes in brain function and structure. However, the interplay among handgrip strength, brain functional connectivity, and cognitive function remains poorly elucidated. Hence, our study sought to examine these relationships in 148 community-dwelling older adults. Specifically, we examined functional segregation, a measure of functional brain organization sensitive to ageing and cognitive decline, and its associations with handgrip strength and cognitive function. We showed that higher handgrip strength was related to better processing speed, attention, and global cognition. Further, higher handgrip strength was associated with higher segregation of the salience/ventral attention network, driven particularly by higher salience/ventral attention intra-network functional connectivity of the right anterior insula to the left posterior insula/frontal operculum and right midcingulate/medial parietal cortex. Importantly, these handgrip strength-related inter-individual differences in salience/ventral attention network functional connectivity were linked to cognitive function, as revealed by functional decoding and brain-cognition association analyses. Our findings thus highlight the importance of the salience/ventral attention network in handgrip strength and cognition, and suggest that inter-individual differences in salience/ventral attention network segregation and intra-network connectivity could underpin the handgrip strength-cognition relationship in older adults.

Correlates of physical activity levels, muscle strength, working memory, and cognitive function in older adults

Objective

To explore the relationship between physical activity level, muscle strength, working memory and cognitive function in older adults.

Methods

A cross-sectional research design was employed to recruit 120 older adults individuals aged 70 and above. Participants were asked to complete the International Physical Activity Questionnaire-Short Form and the Montreal Cognitive Assessment Scale. Data on variables such as grip strength and performance on the N-back task were collected. Data analysis involved the use of independent samples t-tests, χ2 tests, linear regression analysis, Pearson correlation analysis, and one-way analysis of variance (ANOVA).

Results

The detection rate of cognitive dysfunction in older adults was 53.211%; 1-back correct rate had an explanatory power of 11.6% for the cognitive function scores of older adults (R2 = 0.116, p < 0.001); grip strength showed a significant positive correlation with 1-back correct rate (r = 0.417, p < 0.001), and was significantly correlated with the 0-back response time (r = -0.478), 1 -back response time (r = -0.441) were significantly negatively correlated (p < 0.001); physical activity level was significantly positively correlated with grip strength (r = 0.559, p < 0.001), and the difference in grip strength among older adults with different physical activity levels was statistically significant (F = 19.685, p < 0.001).

Conclusion

Physical activity level, muscle strength, working memory, and cognitive function are closely related in older adults, and the relational pathway of physical activity → muscle strength → working memory → cognitive function may serve as a useful addition to promote the field of cognitive research in older adults. To identify and prevent cognitive decline in older adults, physical activity questionnaires, grip strength tests, and 1-back task tests can be extended to nursing homes and communities.

Cardiorespiratory Fitness and Muscular Strength Do Not Predict Social Cognitive Capacity in Older Age

OBJECTIVES

Social cognitive function often declines in older age but the mechanisms underlying these declines are not completely clear. Cardiorespiratory fitness (CRF) and muscular strength are positively associated with broader cognitive function in older adults, yet surprisingly, no study has examined whether a similar relationship exists between CRF or muscular strength and social cognition in older age.

METHODS

We assessed whether higher CRF and muscular strength were associated with enhanced social cognitive function in a sample of fifty older adults (Mage = 70.08, standard deviation = 3.93). Participants completed a gold-standard cardiopulmonary exercise test to assess CRF, an isometric handgrip strength test to index muscular strength, and validated measures of social cognition to index emotion perception and theory of mind (ToM).

RESULTS

The results showed that CRF and muscular strength did not explain any unique variance in older adults' social cognitive performance. Bayesian analyses confirmed that the evidence for the null hypothesis was moderate for all tested relationships, except for the relationship between CRF and cognitive ToM where the evidence for the null was anecdotal.

DISCUSSION

This study has provided the first evidence to suggest that CRF and muscular strength-two important modifiable lifestyle factors-are not associated with social cognition in healthy older adults. However, replication studies are now needed to cross-validate these findings and to clarify whether any moderating variables may be important for understanding the relationship between fitness and social cognition in older age.

Causality between sarcopenia-related traits and major depressive disorder: A bi-directional, two-sample Mendelian randomized study

Observational studies have demonstrated an association between sarcopenia and depression. However, these studies may be influenced by confounding factors, and the causal relationship between sarcopenia and major depressive disorder (MDD) remains unclear. This study aimed to apply the Mendelian randomization (MR) method to address confounding factors and assess the causal effect of sarcopenia on MDD. A two-way, two-sample MR method was employed in this study. Instrumental variables of genome-wide significance level were obtained from the open large-scale genome-wide association study summary data. MR analysis was conducted using inverse variance weighted, MR-Egger, and weighted median methods. The reliability of the results was verified using the heterogeneity test, pleiotropy test, and leave-one-out method for sensitivity analysis. Grip strength (right-hand grip strength: odds ratio [OR] = 0.880, 95% confidence interval [CI] 0.786-0.987, P = .027; left-hand grip strength: OR = 0.814, 95% CI 0.725-0.913, P < .001) and usual walking pace (OR = 0.673, 95% CI 0.506-0.896, P = .007) exhibited a direct causal effect on MDD. MDD had a significant causal effect on appendicular lean mass (β = -0.065, 95% CI -0.110, -0.019, P = .005). There was a causal relationship between sarcopenia-related traits and MDD. Loss of muscle strength, rather than skeletal muscle mass, is correlated with an increased risk of MDD. Furthermore, individuals with MDD are more likely to experience loss of skeletal muscle mass.

Examining individual learning patterns using generalised linear mixed models

Everyone learns differently, but individual performance is often ignored in favour of a group-level analysis. Using data from four different experiments, we show that generalised linear mixed models (GLMMs) and extensions can be used to examine individual learning patterns. Producing ellipsoids and cluster analyses based on predicted random effects, individual learning patterns can be identified, clustered and used for comparisons across various experimental conditions or groups. This analysis can handle a range of datasets including discrete, continuous, censored and non-censored, as well as different experimental conditions, sample sizes and trial numbers. Using this approach, we show that learning a face-named paired associative task produced individuals that can learn quickly, with the performance of some remaining high, but with a drop-off in others, whereas other individuals show poor performance throughout the learning period. We see this more clearly in a virtual navigation spatial learning task (NavWell). Two prominent clusters of learning emerged, one showing individuals who produced a rapid learning and another showing a slow and gradual learning pattern. Using data from another spatial learning task (Sea Hero Quest), we show that individuals' performance generally reflects their age category, but not always. Overall, using this analytical approach may help practitioners in education and medicine to identify those individuals who might need extra help and attention. In addition, identifying learning patterns may enable further investigation of the underlying neural, biological, environmental and other factors associated with these individuals.

Prevalence of dynapenia and overlap with disability, depression, and executive dysfunction

OBJECTIVE

This study aims to investigate handgrip strength and dynapenia prevalence among older adults stratified by Brazilian macroregions. Additionally, we aim to evaluate the overlap between dynapenia and Instrumental Activities of Daily Living (IADL) disability, depression, and executive dysfunction on a national basis and by each Brazilian macroregion.

METHODS

This cross-sectional analysis was based on data from the Brazilian Longitudinal Study of Aging (ELSI-Brazil). A multistage cluster sample design was used, with a representative population-based study of non-institutionalized community-dwelling Brazilians aged ≥ 50 years from 70 municipalities across all five macroregions of the country. The outcome variable was dynapenia. Covariables were IADL disability, depression, and executive dysfunction. The Brazilian macroregions were used for stratification. In addition, the following additional variables were included: age group, gender, education level, macroregions (North, Northeast, Southeast, South, and Midwest), self-reported health, multimorbidity, and falls.

RESULTS

A total of 8,849 (94%) of the sample provided complete information for the handgrip strength assessment and were included in this analysis. Dynapenia prevalence was higher in North and Northeast regions (28.5% and 35.1%, respectively). We identified statistically significant differences between different macroregions for dynapenia, IADL disability, and verbal fluency, with worse values in the North and Northeast regions. In the North and Northeast macroregions, nearly half of the subjects that presented executive dysfunction and IADL disability also had dynapenia. There was a more significant overlap in the prevalence of all four conditions in the North and Northeast regions (4.8% and 5.5%, respectively), whereas the overlap was smaller in the South (2.3%). There was also a smaller overlap in the prevalence of dynapenia and depression in the South (5.8%) compared with other macroregions.

CONCLUSIONS

Macroregions in Brazil exhibit marked differences in the prevalence of dynapenia and in its overlap with IADL disability, depression, and executive dysfunction.

Elevated C-reactive protein mediates the liver-brain axis: a preliminary study

BACKGROUND

Chronic liver diseases of all etiologies exist along a spectrum with varying degrees of hepatic fibrosis. Despite accumulating evidence implying associations between liver fibrosis and cognitive functioning, there is limited research exploring the underlying neurobiological factors and the possible mediating role of inflammation on the liver-brain axis.

METHODS

Using data from the UK Biobank, we examined the cross-sectional association of liver fibrosis (as measured by Fibrosis-4 score) with cognitive functioning and regional grey matter volumes (GMVs) while adjusting for numerous covariates and multiple comparisons. We further performed post-hoc preliminary analysis to investigate the mediating effect of C-reactive protein (CRP) on the association between liver fibrosis and both cognitive functioning and GMVs.

FINDINGS

We analysed behaviour from up to 447,626 participants (N ranged from 45,055 to 447,533 per specific cognitive metric) 37 years and older. 38,244 participants (age range 44-82 years) had GMV data collected at a median 9-year follow-up. Liver fibrosis showed significant associations with cognitive performance in reasoning, working memory, visual memory, prospective memory, executive function, and processing speed. Subgroup analysis indicated larger effects sizes for symbol digital substitution but smaller effect sizes for trail making in middle-aged people than their old counterparts. Neuroimaging analyses revealed significant associations between liver fibrosis and reduced regional GMVs, primarily in the hippocampus, thalamus, ventral striatum, parahippocampal gyrus, brain stem, and cerebellum. CRP levels were significantly higher in adults with advanced liver fibrosis than those without, indicating an elevated systemic inflammation. Moreover, the serum CRP significantly mediated the effect of liver fibrosis on most cognitive measures and regional GMVs in the hippocampus and brain stem.

INTERPRETATION

This study provides a well-powered characterization of associations between liver fibrosis, cognitive impairment, and grey matter atrophy. It also highlights the possibly mediating role of systemic inflammation on the liver-brain axis. Early surveillance and prevention of liver diseases may reduce cognitive decline and brain GMV loss.

FUNDING

National Science Foundation, and National Institutes of Health.

Association between physical activity and global functioning in individuals with mental disorders: A systematic review and meta-analysis

Physical activity is associated with better global functioning in the general population and in people with physical conditions. However, there is no meta-analytic evidence on the associations between daily physical activity levels and global functioning in people with mental disorders. The objective of the present meta-analysis therefore was to evaluate the associations between daily physical activity levels and global functioning in individuals with mental disorders. Pubmed, Embase, PsycINFO and SPORTdiscus were searched from inception to August 1st, 2022. Risk of bias was assessed using the National Institutes of Health Study Quality Assessment Tools. A random-effects meta-analysis was performed. Ten studies were identified and six were meta-analyzed including 251 adults (39.2 ± 11.9 years, 33.6% of women). The pooled results from six studies found a moderate positive correlation (r = 0.39, 95% CI 0.242 to 0.528, p<0.001, I²=49.3%) between daily physical activity and global functioning. Three out of four studies not included in the meta-analysis also found significant associations between physical activity and global functioning. The current meta-analysis demonstrated a moderate association between daily physical activity and global functioning in individuals with mental disorders. However, the evidence is based on cross-sectional studies and a causal relationship cannot be established. High-quality longitudinal studies aiming to address this relationship should be conducted.

Preventive health examinations: protocol for a prospective cross-sectional study of German employees aged 45 to 59 years (Ü45-check)

Objective

Early identification of health-related risk factors is of great importance for maintaining workability. Screening examinations can help to detect diseases at an early stage and provide more needs-based recommendations. This study aims (1) to assess the individual need for prevention or rehabilitation based on preventive health examinations compared to a questionnaire survey, (2) to assess the results of the preventive health examinations compared to the Risk Index - Disability Pension (RI-DP), (3) to assess the results of the questionnaire survey compared to the RI-DP, (4) to assess the general health status of the sample (target population > 1,000) in German employees aged 45-59, (5) to identify the most common medical conditions. A further study question aims, and (6) to investigate the general health status of the specific occupational groups.

Methods

Comprehensive diagnostics including medical examination, anamnesis, anthropometric measurements, bioelectrical impedance analysis (BIA), handgrip strength, resting electrocardiogram (ECG), resting blood pressure, pulse wave velocity (PWV), and laboratory blood analyses added by a questionnaire are conducted. The research questions are analyzed in an exploratory manner.

Results and conclusion

We expect that the results will allow us to formulate recommendations regarding screening for prevention and rehabilitation needs on a more evidence-based level.Clinical Trial Registration: DRKS ID: DRKS00030982.

Associations of physical frailty with health outcomes and brain structure in 483 033 middle-aged and older adults: a population-based study from the UK Biobank

BACKGROUND

Physical frailty is a state of increased vulnerability to stressors and is associated with serious health issues. However, how frailty affects and is affected by numerous other factors, including mental health and brain structure, remains underexplored. We aimed to investigate the mutual effects of frailty and health using large, multidimensional data.

METHODS

For this population-based study, we used data from the UK Biobank to examine the pattern and direction of association between physical frailty and 325 health-related measures across multiple domains, using linear mixed-effect models and adjusting for numerous confounders. Participants were included if complete data were available for all five indicators of frailty, all covariates, and at least one health measure. We further examined the association between frailty and brain structure and the role of this association in mediating the relationship between frailty and health outcomes.

FINDINGS

483 033 participants aged 38-73 years were included in the study at baseline (between Dec 19, 2006, and Oct 1, 2010); at a median follow-up of 9 years (IQR 8-10), behavioural data were available for 46 501 participants and neuroimaging data for 40 210 participants. The severity of physical frailty was significantly associated with decreased cognitive performance (Cohen's d=0·025-0·162), increased early-life risks (d=0·026-0·111), unhealthy lifestyle (d=0·013-0·394), poor physical fitness (d=0·007-0·668), increased symptoms of poor mental health (d=0·032-0·607), severe environmental pollution (d=0·013-0·064), and adverse biochemical markers (d=0·025-0·198). Some associations were bidirectional, with the strongest effects on mental health measures. The severity of frailty correlated with increased total white matter hyperintensity and lower grey matter volume, particularly in subcortical regions (d=0·027-0·082), which significantly mediated the association between frailty and health-related outcomes, although the mediated effects were small.

INTERPRETATION

Physical frailty is associated with diverse unfavourable health-related outcomes, which can be mediated by differences in brain structure. Our findings offer a framework for guiding preventative strategies targeting both frailty and psychiatric disorders.

FUNDING

National Institute of Mental Health, National Science Foundation.

Effects of home-based manual dexterity training on cognitive function among older adults: a randomized controlled trial

BACKGROUND

The relationship between manual dexterity and cognitive function among older adults is well known; however, few studies have focused on manual dexterity training that confirms cognitive load of training in older adults through functional near-infrared spectroscopy (fNIRS) and verifies the effect of training. This study examined the effects of home-based manual dexterity training on cognitive function in older adults using a digital trail-making peg test device combining two conventional assessment tools namely, the peg and trail-making tests.

METHODS

For 12 weeks, 57 healthy older adults aged 65-88 years participated in a parallel-group, randomized controlled trial, wherein home-based manual dexterity training was performed for approximately 20 min daily. To quantify the cognitive load in different manual dexterity conditions, we assessed the cortical activation patterns of the prefrontal cortex via a wearable four-channel fNIRS device. Participants in the control group were asked to continue their usual daily routines during the intervention period. Cognitive function was assessed using the Stroop Color and Word and Cognitive Impairment Tests. Manual dexterity was assessed using the Purdue Pegboard Test. All outcomes were estimated before and after the intervention.

RESULTS

We observed significant differences in prefrontal cortical activation between the different manual dexterity conditions. Only the intervention group showed a significant improvement in Stroop interference (169.0-108.9 ms, p = 0.032) and an executive function and assembly task of the Purdue Pegboard Test (22.5-26.4 counts, p < 0.001). Additionally, except the clock drawing task, cognitive function had a larger effect size (Cohen's d) in the intervention group (d = 0.26-0.45) than in the control group (d = 0.11-0.28).

CONCLUSIONS

Home-based manual dexterity training can improve performance in a complex manual dexterity task and executive functioning in older adults.

TRIAL REGISTRATION

UMIN-CTR Clinical Trial, UMIN000047203. Registered 17 March 2022 - Retrospectively registered, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&recptno=R000053844&type=summary&language=E.

Interactive relationships of Type 2 diabetes and bipolar disorder with cognition: evidence of putative premature cognitive ageing in the UK Biobank Cohort

Type 2 diabetes (T2D) is disproportionately prevalent in bipolar disorder (BD) and is associated with cognitive deficits in psychiatrically healthy cohorts. Whether there is an interaction effect between T2D and BD on cognition remains unclear. Using the UK Biobank, we explored interactions between T2D, BD and cognition during mid and later life; and examined age-related cognitive performance effects in BD as a function of T2D. Data were available for 1511 participants with BD (85 T2D), and 81,162 psychiatrically healthy comparisons (HC) (3430 T2D). BD and T2D status were determined by validated measures created specifically for the UK Biobank. Diagnostic and age-related associations between T2D status and cognition were tested using analyses of covariance or logistic regression. There was a negative association of T2D with visuospatial memory that was specific to BD. Processing speed and prospective memory performance were negatively associated with T2D, irrespective of BD diagnosis. Cognitive deficits were evident in BD patients with T2D compared to those without, with scores either remaining the same (processing speed) or improving (visuospatial memory) as a function of participant age. In contrast, cognitive performance in BD patients without T2D was worse as participant age increased, although the age-related trajectory remained broadly equivalent to the HC group. BD and T2D associated with cognitive performance deficits across the mid-life period; indicating comorbid T2D as a potential risk factor for cognitive dysfunction in BD. In comparison to BD participants without T2D and HCs, age-independent cognitive impairments in BD participants with comorbid T2D suggest a potential premature deterioration of cognitive functioning compared to what would normally be expected.

Handgrip Strength Cutoff Value Among Korean Adolescents with Metabolic Syndrome Components: Korean National Health and Nutrition Examination Survey Data 2014-2017

Abstract Objectives: To propose the cutoff value of handgrip strength (HGS) for each metabolic syndrome component in Korean adolescents. Methods: Total of 2303 adolescents (1226 boys and 1077 girls; age 10-18 years) who participated in the Korea National Health and Nutrition Examination Survey from 2014 to 2017. We used the International Diabetes Federation metabolic syndrome guideline for children to define metabolic syndrome. The highest HGS for both hands were recorded. The optimal HGS cutoff for predicting metabolic syndrome components was determined by receiver operating characteristic curve analysis. Results: Adolescents with metabolic syndrome components defined by each criterion had higher HGS, systolic blood pressure, waist circumference, body mass index, fasting glucose, cholesterol, triglyceride (TG), alanine aminotransferase, and aspartate aminotransferase compared with average participants' data. The cutoff value of HGS defining waist circumference, TG level, high-density lipoprotein, and blood pressure was 24, 21.5, 30.9, and 30.2, respectively. The cutoff value of HGS defining metabolic syndrome was 28.9. For HGS to body weight ratio, the cutoff value defining metabolic syndrome was 0.38. Conclusions: This study showed that cutoff values of HGS have relation with metabolic syndrome in adolescents. Although cutoff has been suggested, it may not be sufficient for clinical use. Additional data are need to be accumulated in actual clinical trials for more accurate cutoff HGS value.

Associations between grip strength, brain structure, and mental health in > 40,000 participants from the UK Biobank

BACKGROUND

Grip strength is a widely used and well-validated measure of overall health that is increasingly understood to index risk for psychiatric illness and neurodegeneration in older adults. However, existing work has not examined how grip strength relates to a comprehensive set of mental health outcomes, which can detect early signs of cognitive decline. Furthermore, whether brain structure mediates associations between grip strength and cognition remains unknown.

METHODS

Based on cross-sectional and longitudinal data from over 40,000 participants in the UK Biobank, this study investigated the behavioral and neural correlates of handgrip strength using a linear mixed effect model and mediation analysis.

RESULTS

In cross-sectional analysis, we found that greater grip strength was associated with better cognitive functioning, higher life satisfaction, greater subjective well-being, and reduced depression and anxiety symptoms while controlling for numerous demographic, anthropometric, and socioeconomic confounders. Further, grip strength of females showed stronger associations with most behavioral outcomes than males. In longitudinal analysis, baseline grip strength was related to cognitive performance at ~9 years follow-up, while the reverse effect was much weaker. Further, baseline neuroticism, health, and financial satisfaction were longitudinally associated with subsequent grip strength. The results revealed widespread associations between stronger grip strength and increased grey matter volume, especially in subcortical regions and temporal cortices. Moreover, grey matter volume of these regions also correlated with better mental health and considerably mediated their relationship with grip strength.

CONCLUSIONS

Overall, using the largest population-scale neuroimaging dataset currently available, our findings provide the most well-powered characterization of interplay between grip strength, mental health, and brain structure, which may facilitate the discovery of possible interventions to mitigate cognitive decline during aging.

Lower grip strength and insufficient physical activity can increase depressive symptoms among middle-aged and older European adults: a longitudinal study

Objectives

The present study aimed to identify the gender-specific trajectories of grip strength using group-based trajectories, explore the interaction between grip strength and physical activity on depression, and investigate the association of physical activity with the change in depression by different grip strength groups among middle-aged and older European adults.

Methods

A total of 14,098 participants aged 50 years or older from the Survey of Health, Ageing and Retirement in Europe 2007–2019 were included in this study. Group-based trajectory modeling was used to identify the low, middle and high group of grip strength by gender. Generalized estimated equations were fitted to analyze the interaction effect. The data of wave 2-wave 5 and wave 2-wave 7 were chosen to conduct sensitivity analyses.

Results

Significant interactions between grip strength group and physical inactivity were found (x²_interaction = 11.16, P = 0.004). Significant interactions between physical inactivity and time on depression were identified in low (x²_interaction = 27.83, P < 0.001) and moderate (x²_interaction = 23.67, P < 0.001) grip strength, but a similar result was not found in high grip strength (x²_interaction = 4.39, P = 0.495). Participants in the physical inactivity group had higher depression scores in the low and moderate grip strength groups. Sensitivity analyses yield almost similar results.

Conclusions

Grip strength and physical inactivity interact with depression. Lower grip strength and insufficient physical activity can increase depressive symptoms. People with lower grip strength and physical inactivity should pay special attention to the prevention of depression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03392-x.

Sarcopenia in community-dwelling older adults is associated with the diversity and composition of the gut microbiota

Sarcopenia is a prognostic indicator of negative consequences in older adults, including physical disability, frailty, and mortality. Few studies have investigated the associations between sarcopenia and the gut microbiota. We sought such associations in community-dwelling older adults aged ≥60 years. Sarcopenia was defined as low muscle mass, plus reduced physical performance, and/or low skeletal muscle strength. 16S rRNA next-generation sequencing was used to identify the components of the gut microbiota in fecal samples from 27 older adults with sarcopenia and 33 without sarcopenia. Relationships between sarcopenia and the diversity and composition of the gut microbiota were analyzed. Diversities at the species level were detected between the sarcopenia and control groups (P = 0.049). The abundance of Prevotella and Prevotella copri was significantly lower (P = 0.021 and P = 0.018 respectively) and that of Parabacteroides sp. higher in the sarcopenia than the control group (P = 0.010). Linear discriminant analysis of effect size revealed differences in the microbiota composition between the two groups. Sarcopenia was related with the presence of Anaerotruncus and Phascolarctobacterium sp. and the absence of Prevotella sp. and Prevotella copri. Further research is warranted to clarify whether changes in the gut microbiota cause sarcopenia onset or development.

Association Between Grip Strength and Cognitive Function in US Older Adults of NHANES 2011–2014

Background: The relationship between grip strength and cognitive function remains no consensus in the older adults. Objective: To investigate the association of grip strength with cognitive function and cognitive performance in different domains. Methods: Participants of the present cross-sectional study were from the National Health and Nutrition Examination Survey 2011-2014. Grip strength was measured by grip dynamometer, and combined handgrip strength was the sum of the largest reading from each hand. Four cognitive domains (immediate and delayed memory, language, and attention) were assessed by a set of neuropsychological tests. The subjective cognitive decline was determined via self-report. Results: Among 2,618 participants, combined grip strength was positively associated with scores on global cognitive function and each cognitive domain after controlling for demographic characteristics, lifestyle factors, and history of disease. In addition, compared to those with grip strength <  46.7 kg, participants with grip strength≥75.3 kg had odds ratios of 0.36 (95% CI: 0.21 to 0.63) for poor global cognitive function, 0.66 (95% CI: 0.38 to 1.13) for poor immediate memory, 0.53 (95% CI: 0.30 to 0.93) for poor delayed memory, 0.48 (95% CI: 0.27 to 0.86) for poor language function, 0.20 (95% CI: 0.11 to 0.35) for poor attention, and 0.36 (95% CI: 0.18 to 0.73) for subjective cognitive decline in fully adjusted model. Conclusion: Older adults with higher grip strength were significantly associated with better performance on cognition function included global and various domains such as memory, language, attention, and subjective cognitive decline.

Cognitive abilities of institutionalized older persons with depressive symptoms

ABSTRACT Objective To determine the level of association between depressive symptoms and cognitive abilities of institutionalized older adults. Methods This is a cross-sectional study that enrolled 69 older adults, living in a long-term care facility. Investigation of depressive symptoms in all individuals was performed using the geriatric depression scale. Cognitive verbal fluency, digit span forward (DSF) and backward (DSB) tests, and two-minute stationary gait, sit-to-stand test, and six-minute walk test were performed to assess their association with depressive symptoms. Results Depressive symptoms were identified in 35 individuals. Worse cognition and physical performances were associated with the presence of depressive symptoms – Mini-Mental State Examination [t (61) = 2.36; p < 0.05] and Stationary gait test of two minutes [t (53) = 3.12; p < 0.05]. Short-term memory and working memory tests presented worse results in individuals with depressive symptoms (DSF: U = 402.00; p < 0.05 e DSB: U = 341,00; p < 0.05). Older adults with scores below normal in DSF were 5 times more likely to exhibit depressive symptoms. Conclusion The importance of physical, cognitive and social intervention strategies in long-term care facilities for the older adults is highlighted, in order to privilege autonomy. Notably, there is an association between deficits in short-term memory and the presence of depressive symptoms in older adults. Therefore, prospective studies are suggested to investigate the cause-effect relationship of this association with the institutionalization of older adults.

The Association Between Grip Strength and Depression Among Adults Aged 60 Years and Older: A Large-Scaled Population-Based Study From the Longitudinal Aging Study in India

Background

The association between grip strength and depression in elderly individuals in low- and middle-income countries (LMICs) has rarely been studied. This study aims to explore the relevance of grip strength and depression in the elderly population using data from a national large-scale population.

Methods

This study was conducted using data from seniors over 60 years old in wave 1 of the Longitudinal Aging Study in India (LASI). Grip strength is the maximum of three measurements by the dynamometer. Depression symptoms were assessed using 10 items on the Center for Epidemiologic Studies Depression Scale (CESD-10) with a 10-point boundary. Multivariate linear regression analysis, non-linear analysis, subgroup analysis, interaction tests and sensitivity analysis were performed.

Results

There were 27,343 participants in this study, including 19,861 participants with low grip strength and 7,482 participants with normal grip strength. The results revealed that grip strength and depression were negatively correlated in elderly individuals after adequate adjustment for confounding factors [odds ratio (OR) = 1.237, 95% confidence interval (CI) 1.172–1.305, p < 0.00001]. The results remained stable after adjusting for all confounding factors (OR = 1.090, 95% CI 1.030–1.155, p = 0.00307). Regression analysis showed that physical activity (PA), comorbidities and cognition may have an impact on the correlation between grip strength and depression symptoms. Smooth curve fit suggested that grip strength and depressive symptoms were linearly related. The interaction test results of gender in the relationship between grip strength and depression were significant (p for interaction < 0.05).

Conclusion

Grip strength and depression were negatively correlated in older Indians, and larger prospective studies are needed in the future to determine this association.

The Link Between Energy-Related Sensations and Metabolism: Implications for Treating Fatigue

Energy-related sensations include sensation of energy and fatigue as well as subjective energizability and fatigability. First, we introduce interdisciplinary useful definitions of all constructs and review findings regarding the question of whether sensations of fatigue and energy are two separate constructs or two ends of a single dimension. Second, we describe different components of the bodily energy metabolism system (e.g., mitochondria; autonomic nervous system). Third, we review the link between sensation of fatigue and different components of energy metabolism. Finally, we present an overview of different treatments shown to affect both energy-related sensations and metabolism before outlining future research perspectives.

Cognitive impairment and World Trade Centre-related exposures

On 11 September 2001 the World Trade Center (WTC) in New York was attacked by terrorists, causing the collapse of multiple buildings including the iconic 110-story 'Twin Towers'. Thousands of people died that day from the collapse of the buildings, fires, falling from the buildings, falling debris, or other related accidents. Survivors of the attacks, those who worked in search and rescue during and after the buildings collapsed, and those working in recovery and clean-up operations were exposed to severe psychological stressors. Concurrently, these 'WTC-affected' individuals breathed and ingested a mixture of organic and particulate neurotoxins and pro-inflammogens generated as a result of the attack and building collapse. Twenty years later, researchers have documented neurocognitive and motor dysfunctions that resemble the typical features of neurodegenerative disease in some WTC responders at midlife. Cortical atrophy, which usually manifests later in life, has also been observed in this population. Evidence indicates that neurocognitive symptoms and corresponding brain atrophy are associated with both physical exposures at the WTC and chronic post-traumatic stress disorder, including regularly re-experiencing traumatic memories of the events while awake or during sleep. Despite these findings, little is understood about the long-term effects of these physical and mental exposures on the brain health of WTC-affected individuals, and the potential for neurocognitive disorders. Here, we review the existing evidence concerning neurological outcomes in WTC-affected individuals, with the aim of contextualizing this research for policymakers, researchers and clinicians and educating WTC-affected individuals and their friends and families. We conclude by providing a rationale and recommendations for monitoring the neurological health of WTC-affected individuals.

A Link between Handgrip Strength and Executive Functioning: A Cross-Sectional Study in Older Adults with Mild Cognitive Impairment and Healthy Controls

Older adults with amnestic mild cognitive impairment (aMCI) who in addition to their memory deficits also suffer from frontal-executive dysfunctions have a higher risk of developing dementia later in their lives than older adults with aMCI without executive deficits and older adults with non-amnestic MCI (naMCI). Handgrip strength (HGS) is also correlated with the risk of cognitive decline in the elderly. Hence, the current study aimed to investigate the associations between HGS and executive functioning in individuals with aMCI, naMCI and healthy controls. Older, right-handed adults with amnestic MCI (aMCI), non-amnestic MCI (naMCI), and healthy controls (HC) conducted a handgrip strength measurement via a handheld dynamometer. Executive functions were assessed with the Trail Making Test (TMT A&B). Normalized handgrip strength (nHGS, normalized to Body Mass Index (BMI)) was calculated and its associations with executive functions (operationalized through z-scores of TMT B/A ratio) were investigated through partial correlation analyses (i.e., accounting for age, sex, and severity of depressive symptoms). A positive and low-to-moderate correlation between right nHGS (rp (22) = 0.364; p = 0.063) and left nHGS (rp (22) = 0.420; p = 0.037) and executive functioning in older adults with aMCI but not in naMCI or HC was observed. Our results suggest that higher levels of nHGS are linked to better executive functioning in aMCI but not naMCI and HC. This relationship is perhaps driven by alterations in the integrity of the hippocampal-prefrontal network occurring in older adults with aMCI. Further research is needed to provide empirical evidence for this assumption.

Age-related changes in physiology in individuals with bipolar disorder

BACKGROUND

Individuals with bipolar disorder have a reduced life expectancy and may experience accelerated biological ageing. In individuals with bipolar disorder and healthy controls, we examined differences in age-related changes in physiology.

METHODS

UK Biobank recruited more than 500,000 participants, aged 37-73, between 2006 and 2010. Generalised additive models were used to examine associations between age and grip strength, cardiovascular function, body composition, lung function and heel bone mineral density.

RESULTS

The main dataset included 271,118 adults (mean age = 56.04 years; 49.60% females). We found statistically significant differences between cases and controls for grip strength, blood pressure, pulse rate and body composition, with standardised mean differences of up to -0.24 (95% CI -0.28 to -0.19). Evidence of differences in lung function, heel bone mineral density or arterial stiffness was limited. Case-control differences were most evident for age-related changes in cardiovascular function (both sexes) and body composition (females). Differences did not uniformly narrow or widen with age and differed by sex. For example, the difference in systolic blood pressure between male cases and controls was -1.3 mmHg at age 50 and widened to -4.7 mmHg at age 65. Diastolic blood pressure in female cases was 1.2 mmHg higher at age 40 and -1.2 mmHg lower at age 65.

LIMITATIONS

Analyses did not distinguish between bipolar disorder subtypes. Results may not generalise to other age groups.

CONCLUSIONS

Differences between bipolar disorder cases and controls were most evident for cardiovascular and body composition measures. Targeted screening for cardiovascular and metabolic health in middle age is warranted to potentially mitigate excess mortality.

Effect of Exercise on Secondary Sarcopenia: A Comprehensive Literature Review

Simple Summary

Sarcopenia is an inevitable component of aging. It is officially recognized as a muscle disease with an ICD-10-MC diagnosis code that can be used to bill for care in some countries. Sarcopenia can be classified into primary or age-related sarcopenia and secondary sarcopenia. The condition is referred to as secondary sarcopenia when any other comorbidities are present in conjunction with aging. Secondary sarcopenia is more prevalent than primary sarcopenia and requires special attention. Exercise interventions may help in our understanding and prevention of sarcopenia with a specific morbidity Glomerular filtration rate that exercise improves muscle mass, quality or physical function in elderly subjects with cancer, type 2 diabetes, kidney diseases and lung diseases. In this review, we summarize recent research that has studied the impact of exercise on patients with secondary sarcopenia, specifically those with one comorbid condition. We did not discover any exercise intervention specifically for subjects with secondary sarcopenia (with one comorbidity). Even though there is a strong argument for using exercise to improve muscle mass, quality or physical function in subjects with cancer, type 2 diabetes, kidney diseases, lung diseases and many more, very few studies have reported baseline sarcopenia assessments. Based on the trials summarized in this review, we may propose but not conclude that resistance, aerobic, balance training or even walking can be useful in subjects with secondary sarcopenia with only one comorbidity due to the limited number of trials. This review is significant because it reveals the need for broad-ranging research initiatives involving secondary sarcopenic patients and highlights a large secondary sarcopenia research gap.

Abstract

Background: Sarcopenia has been recognized as an inevitable part of aging. However, its severity and the age at which it begins cannot be predicted by age alone. The condition can be categorized into primary or age-related sarcopenia and secondary sarcopenia. Sarcopenia is diagnosed as primary when there are no other specific causes. However, secondary sarcopenia occurs if other factors, including malignancy or organ failure, are evident in addition to aging. The prevalence of secondary sarcopenia is far greater than that of primary sarcopenia and requires special attention. To date, nutrition and exercise have proven to be the best methods to combat this disease. The impact of exercise on subjects suffering from sarcopenia with a specific morbidity is worthy of examination for understanding and prevention. The purpose of this review, therefore, is to summarize recent research that has investigated the impact of exercise in patients with secondary sarcopenia, specifically with one comorbidity. Methods: Pubmed, Web of Science, Embase and Medline databases were searched comprehensively with no date limit for randomized controlled trials. The literature was specifically searched for clinical trials in which subjects were sarcopenic with only one comorbidity participating in an exercise intervention. The most visible comorbidities identified and used in the search were lung disease, kidney disease, heart disease, type 2 diabetes, cancer, neurological diseases, osteoporosis and arthritis. Results: A total of 1752 studies were identified that matched the keywords. After removing duplicates, there were 1317 articles remaining. We extracted 98 articles for full screening. Finally, we included 21 relevant papers that were used in this review. Conclusion: Despite a strong rationale for using exercise to improve muscle mass, quality or physical function in subjects with cancer, type 2 diabetes, kidney disease, lung disease and many more, baseline sarcopenia evaluation has been reported in very few trials. The limited number of studies does not allow us to conclude that exercise can improve sarcopenia in patients with other comorbidities. This review highlights the necessity for wide-ranging research initiatives involving secondary sarcopenic patients.

Interaction of declined handgrip strength and HIV infection on neurocognitive impairment

Neurocognitive impairment (NCI) persists among people living with HIV (PLWH) despite the success of combination antiretroviral therapy (cART). Although muscular waning or decreased handgrip strength has been widely reported to be associated with cognitive erosion in general elders, such association has not been examined in PLWH who commonly experience decreased handgrip strength and NCI. Furthermore, whether HIV infection modifies such association remains to be addressed. A cross-sectional analysis was conducted with 2808 HIV-positive and 5402 HIV-negative adults participating in the baseline survey of the CHART (Comparative HIV and Aging Research in Taizhou) cohort, China, 2017 - 2019. HIV-positive individuals showed weaker handgrip strength than HIV-negative controls (34.0 kg vs 37.7 kg). Multivariate logistic regression analysis indicated that both HIV infection (aOR = 4.35, p < 0.001) and every 5-kg decrease in "Handgrip strength" (aOR = 1.27, p < 0.001) were significantly associated with NCI, and there was a significant interaction between reduced handgrip strength and HIV infection on NCI (aOR = 1.14, p = 0.015). In stratified analyses adjusting for potential confounders, the association between reduced handgrip strength and NCI was significant among PLWH at all age groups but only significant among HIV-negative controls at 30 - 44 and 60 - 89 ages. Handgrip strength decline is significantly associated with the risk of NCI among PLWH. HIV infection may exacerbate the adverse effect of poor handgrip strength on NCI, especially at younger ages. Early detection of handgrip strength decline could facilitate delivery of compensatory strategies or assistive services to PLWH with or at high risk of NCI.

Heterogeneous alterations in thalamic subfields in major depression disorder

BACKGROUND

It is well known that the thalamus is not a unitary and homogeneous entity but a complex and highly connected archeocortical structure. Although many neuroimaging studies have reported alterations in the thalamus in major depressive disorder (MDD), the structural alterations in thalamic subfields remain unclear. This study aimed to investigate changes in gray matter volume (GMV) in thalamic subfields in MDD patients.

METHODS

The present study included structural images of 848 MDD patients and 794 age-matched normal controls (NC) from 17 study sites of the REST-meta-MDD consortium. We performed voxel-based morphometric analyses to calculate the GMV in the entire thalamus and its subfields using three different automated anatomical labeling atlases and subsequently compared the differences between first-episode drug-naïve major depressive disorder (FEDN), recurrent major depressive disorder (RMDD), and NC groups. We also evaluated the relationships between thalamic GMV and clinical symptoms in MDD patients.

RESULTS

Compared to NC, the FEDN patients showed increased GMV in thalamic subfields but not in the entire thalamus, while RMDD patients showed no significant alterations in GMV in the entire thalamus and its subfields. Moreover, the mean GMV in the right anterior thalamus and left anteroventral thalamus in RMDD patients were mildly positively correlated with the Hamilton Anxiety Rating Scale scores.

LIMITATIONS

The main limitations are a single-modal analysis based on T1-weighted MR images and a cross-sectional design.

CONCLUSIONS

Our findings suggest that FEDN and RMDD patients show heterogeneous alterations across thalamic subfields, which may help us understand the pathophysiological mechanisms of MDD.

Relationship between Handgrip Strength and Low-grade Inflammation in Older Adults with Depression

Objective

The relationship among physical functional decline, low-grade inflammation, and depression remains unclear. The aim of this study was to examine the association between hand grip strength (HGS) and high-sensitivity C-reactive protein (hs-CRP) in a large sample with depression.

Methods

This study used data obtained from a representative Korean sample of 9,402 people who participated in the seventh Korean National Health and Nutrition Examination Survey. Physical function was assessed using a digital grip strength dynamometer. Depression was identified using a cutoff of 5 on the Patient Health Questionnaire-9 (PHQ-9), and high hs-CPR level was defined as ≥ 3.0 mg/L.

Results

In older adults (≥ 60 years) with depression, 43.8% of those with high hs-CRP levels had low HGS, compared to 21.8% of those with hs-CRP levels < 3.0 mg/L (p = 0.002). Multivariate analysis revealed that, after adjustments for potentially confounding factors, high hs-CRP was independently associated with lower HGS (B = −2.25; 95% confidence interval = −4.49 to −0.02) in older adults with depression, but not in younger or middle-aged adults with depression.

Conclusion

These findings suggest a significant correlation between physical functional decline and low-grade inflammation in older adults with depression.

Association between physical fitness, body mass index and intelligence quotient in individuals with intellectual disabilities

BACKGROUND

Physical exercise seems to improve cognitive abilities at different physiological levels. Numerous studies have examined the relationship between physical fitness (PF), physical activity and cognition among populations without intellectual disabilities (ID), but very few have addressed this question with respect to people with ID. This study aimed to determine the correlation between intelligence quotient (IQ) and factors related to PF in healthy adults with ID.

METHODS

A multicentre cross-sectional study was conducted in 91 individuals with ID. All participants were assessed with the K-BIT tests and the following test items from the SAMU DIS-FIT Battery: body mass index, handgrip strength (HGS), leg strength, dynamic balance and physical endurance.

RESULTS

Significant differences between men and women were tested by multiple regression. IQ was found to be statistically related to HGS and leg strength, with a medium effect size. Statistical relationships were also found between sex and physical endurance, with a medium effect size, and HGS, with a large effect size.

CONCLUSIONS

The study results highlight relationships between the variables of muscular strength and the participants' IQ. Further studies with experimental designs are needed to enhance the understanding of the relationships between PF and cognition in persons with ID.

How are academic achievement and inhibitory control associated with physical fitness, soil-transmitted helminth infections, food insecurity and stunting among South African primary schoolchildren?

BACKGROUND

Cardiovascular fitness has been associated with both executive function and academic achievement in multiple cohort studies including children and adolescents. However, research is scarce among children from low- and middle-income countries. Hence, this paper focuses on South African primary schoolchildren living in marginalized areas and examines if academic achievement and inhibitory control can be explained by children's age, socioeconomic status, soil-transmitted helminth infections, food insecurity, stunting, grip strength, and cardiorespiratory fitness.

METHODS

The sample of this cross-sectional study consisted of 1277 children (48% girls, mean age: 8.3 years). Data were assessed via questionnaires, stool samples, anthropometric measurements, 20 m shuttle run test, grip strength test, Flanker task, and school grades. Data were analysed with mixed linear regression models with random intercepts for school classes, separately for boys and girls.

RESULTS

Higher socioeconomic status was most closely associated with academic achievement among boys (p < 0.05), whereas higher levels of cardiorespiratory fitness and not being stunted explained most variance in academic achievement in girls (p < 0.05). Higher age turned out to be associated with better performance in the Flanker task (p < 0.01). Additionally, in boys, higher grip strength was associated with better information processing and inhibitory control of attention (p < 0.01), whereas in girls, higher cardiorespiratory fitness levels were positively associated with these cognitive abilities (p < 0.05).

CONCLUSIONS

Academic performance has been shown to be compromised in schoolchildren living in marginalised areas, compared to schoolchildren in less disadvantaged parts of South Africa. The present study suggests that cardiorespiratory fitness and grip strength are two potentially modifiable factors that are associated with children's academic achievement and cognitive performance, and that should be targeted in future school-based interventions.

Reliability and validity of physical fitness tests in people with mental disorders: A systematic review and meta-analysis

BACKGROUND

Several tests are available to assess the different components of physical fitness, including cardiorespiratory fitness, muscular strength, and flexibility. However, the reliability and validity of physical fitness tests in people with mental disorders has not been meta-analyzed.

AIMS

To examine the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders.

METHODS

Studies evaluating the reliability, concurrent, and convergent validity of physical fitness tests in people with mental disorders were searched from major databases until January 20, 2020. Random-effects meta-analyses were performed pooling (1) reliability: test-retest correlations at two-time points, (2) convergent validity between submaximal tests and maximal protocols, or (3) concurrent validity between two submaximal tests. Associations are presented using r values and 95% confidence intervals. Methodological quality was assessed using the Quality Appraisal of Reliability Studies and the Critical Appraisal Tool.

RESULTS

A total of 11 studies (N = 504; 34% females) were included. Reliability of the fitness tests, produced r values ranging from moderate (balance test-EUROFIT; [r = 0.75 (0.60-0.85); p = 0.0001]) to very strong (explosive leg power EUROFIT; [r = 0.96 (0.93-0.97); p = 0.0001]). Convergent validity between the 6-min walk test (6MWT) and submaximal cardiorespiratory tests was moderate (0.57 [0.26-0.77]; p = 0.0001). Concurrent validity between the 2-min walk test and 6MWT (r = 0.86 [0.39-0.97]; p = 0.0004) was strong.

CONCLUSION

The present study demonstrates that physical fitness tests are reliable and valid in people with mental disorders.

Impact of dietary protein intake on the incidence of low muscle strength in middle-aged and older adults

BACKGROUND

A reduction in skeletal muscle strength is a prognostic indicator of negative consequences, such as physical disability, frailty, and mortality in older adults. Studies investigating associations between the risk of reduction in skeletal muscle strength and the amount of dietary protein which is a factor influenced muscle health are scarce, particularly in Asian populations. Therefore, we investigated the association between the amount and change in daily protein intake and the prospective risk of developing low skeletal muscle strength in middle-aged and older adults.

METHODS

This study used data from the Korean Genome and Epidemiology Study as an ongoing population-based cohort study of adults aged 40 years and over. The amount of daily protein consumed was assessed using a semi-quantitative food frequency questionnaire. Low skeletal muscle strength was measured with a handgrip strength dynamometer.

RESULTS

In total, 32,458 adults (11,358 males and 21,100 females) were evaluated. The amount of daily dietary protein consumed was not associated with the risk of low muscle strength over the 4-year follow-up period after adjusting for covariates. No associations between low muscle strength events according to the change in the amount of protein consumed from the baseline to the follow-up surveys were identified.

CONCLUSIONS

The amount of and change in dietary protein consumed were not associated with developing low muscle strength in middle-aged and older adults. Further studies with a focus on physical activity-protein intake interactions and specific conditions, such as mobility-limited adults or hospitalized patients, are warranted to clarify the relationship between protein intake status and the incidence of low skeletal muscle strength.

Cortical hemodynamics as a function of handgrip strength and cognitive performance: a cross-sectional fNIRS study in younger adults

BACKGROUND

There is growing evidence for a positive correlation between measures of muscular strength and cognitive abilities. However, the neurophysiological correlates of this relationship are not well understood so far. The aim of this study was to investigate cortical hemodynamics [i.e., changes in concentrations of oxygenated (oxyHb) and deoxygenated hemoglobin (deoxyHb)] as a possible link between measures of muscular strength and cognitive performance.

METHODS

In a cohort of younger adults (n = 39, 18-30 years), we assessed (i) handgrip strength by a handhold dynamometer, (ii) short-term working memory performance by using error rates and reaction times in the Sternberg task, and (iii) cortical hemodynamics of the prefrontal cortex (PFC) via functional near-infrared spectroscopy (fNIRS).

RESULTS

We observed low to moderate negative correlations (rp =  ~ - 0.38 to - 0.51; p < 0.05) between reaction time and levels of oxyHb in specific parts of the PFC. Furthermore, we noticed low to moderate positive correlations (rp =  ~ 0.34 to 0.45; p < 0.05) between reaction times and levels of deoxyHb in distinct parts of the PFC. Additionally, higher levels of oxyHb (rp (35) = 0.401; p = 0.014) and lower levels of deoxyHb (rp (34) = - 0.338; p = 0.043) in specific parts of the PFC were linked to higher percentage of correct answers. We also found low to moderate correlations (p < 0.05) between measures of handgrip strength and levels of oxyHb (rp =  ~ 0.35; p < 0.05) and levels of deoxyHb (rp =  ~ - 0.25 to - 0.49; p < 0.05) in specific parts of the PFC. However, there was neither a correlation between cognitive performance and handgrip strength nor did cortical hemodynamics in the PFC mediate the relationship between handgrip strength and cognitive performance (p > 0.05).

CONCLUSION

The present study provides evidence for a positive neurobehavioral relationship between cortical hemodynamics and cognitive performance. Our findings further imply that in younger adults higher levels of handgrip strength positively influence cortical hemodynamics although the latter did not necessarily culminate in better cognitive performance. Future research should examine whether the present findings can be generalized to other cohorts (e.g., older adults).

Grip Strength, Neurocognition, and Social Functioning in People WithType-2 Diabetes Mellitus, Major Depressive Disorder, Bipolar Disorder, and Schizophrenia

BACKGROUND

Frailty is a common syndrome among older adults and patients with several comorbidities. Grip strength (GS) is a representative parameter of frailty because it is a valid indicator of current and long-term physical conditions in the general population and patients with severe mental illnesses (SMIs). Physical and cognitive capacities of people with SMIs are usually impaired; however, their relationship with frailty or social functioning have not been studied to date. The current study aimed to determine if GS is a valid predictor of changes in cognitive performance and social functioning in patients with type-2 diabetes mellitus and SMIs.

METHODS

Assessments of social functioning, cognitive performance, and GS (measured with an electronic dynamometer) were conducted in 30 outpatients with type 2 diabetes mellitus, 35 with major depressive disorder, 42 with bipolar disorder, 30 with schizophrenia, and 28 healthy controls, twice during 1-year, follow-up period. Descriptive analyses were conducted using a one-way analysis of variance for continuous variables and the chi-squared test for categorical variables. Differences between groups for the motor, cognitive, and social variables at T1 and T2 were assessed using a one-way analysis of covariance, with sex and age as co-variates (p < 0.01). To test the predictive capacity of GS at baseline to explain the variance in cognitive performance and social functioning at T2, a linear regression analysis was performed (p < 0.05).

RESULTS

Predictive relationships were found among GS when implicated with clinical, cognitive, and social variables. These relationships explained changes in cognitive performance after one year of follow-up; the variability percentage was 67.7%, in patients with type-2 diabetes mellitus and 89.1% in patients with schizophrenia. Baseline GS along with other variables, also predicted changes in social functioning in major depressive disorder, bipolar disorder, and schizophrenia, with variability percentages of 67.3, 36, and 59%, respectively.

CONCLUSION

GS combined with other variables significantly predicted changes in cognitive performance and social functioning in people with SMIs or type-2 diabetes mellitus. Interventions aimed to improve the overall physical conditions of patients who have poor GS could be a therapeutic option that confers positive effects on cognitive performance and social functioning.

Association between Dietary Patterns and Handgrip Strength: Analysis of the Korean National Health and Nutrition Examination Survey Data Between 2014 and 2017

Non-invasive anthropometric measurement methods such as those for measuring height and weight are crucial in pediatric patients. However, research focusing on the association between the type of dietary pattern and handgrip strength and handgrip-to-weight ratio in adolescents has not been carried out yet. This cross-sectional analysis of the 2014–2017 Korean National Health and Nutrition Examination Survey assessed 2327 adolescents (aged 10–18 years) who had their handgrip strength measured and analyzed its association with dietary pattern. The clusters were examined for nutritional values, and the ready-to-eat, balanced, and Western-style fast-food clusters were ultimately generated. Overall, 85.6% of the participants were assigned to a ready-to-eat dietary pattern, 9.3% to a Western-style fast-food dietary pattern, and 5.1% to a balanced dietary pattern. Compared with the participants following a balanced dietary pattern, those following a ready-to-eat dietary pattern were shown to have a significantly lower handgrip strength and handgrip-to-weight ratio. Decreased handgrip strength and handgrip-to-weight ratio values in participants following ready-to-eat dietary patterns indicate a diffuse problem in adolescents’ health and possibly imply an association between reduced muscle quality and dietary pattern. Therefore, the overall environmental factors potentially inducing such unhealthy dietary preferences should be investigated, and appropriate lifestyle changes in Korean adolescents should be encouraged.

Grip Strength and Depression Symptoms Among Middle-Age and Older Adults

OBJECTIVE

To analyze the relationship between grip strength and symptoms of depression, considering sex and age, in adults from 18 countries.

METHODS

Cross-sectional data for adults 50 years and older from the Survey of Health, Aging, and Retirement in Europe wave 6 (collected in 2015) were analyzed. Grip strength was measured twice on each hand using a handgrip dynamometer. The EURO-D 12-item scale was used to measure depression symptoms. Multivariable logistic regression analysis was conducted. Data analyses were conducted between November 5, 2019, and February 7, 2020.

RESULTS

Men and women who were in quartiles 2, 3, and 4 of grip strength were less likely to have depression symptoms than those in the first quartile of grip strength. Having more grip strength decreased the odds of depression symptoms by 30% (odds ratio 0.70; 95% CI, 0.65 to 0.77) and 47% (odds ratio, 0.53; 95% CI, 0.49 to 0.57) for adults aged 50 to 64 years and 65 years and older, respectively, when compared with those with the lowest grip strength. The negative relationship between strong grip strength and depression symptoms was observed among men and women younger and older than 65 years.

CONCLUSION

There was an association between grip strength and depression symptoms. For clinical practice and geriatric health professionals, assessing adults' grip strength can be used as a signal to screen for physical and mental health.

Exercise as Medicine for Mental and Substance Use Disorders: A Meta-review of the Benefits for Neuropsychiatric and Cognitive Outcomes

BACKGROUND

Exercise may improve neuropsychiatric and cognitive symptoms in people with mental disorders, but the totality of the evidence is unclear. We conducted a meta-review of exercise in (1) serious mental illness (schizophrenia spectrum, bipolar disorder and major depression (MDD)); (2) anxiety and stress disorders; (3) alcohol and substance use disorders; (4) eating disorders (anorexia nervosa bulimia nervosa, binge eating disorders, and (5) other mental disorders (including ADHD, pre/post-natal depression).

METHODS

Systematic searches of major databases from inception until 1/10/2018 were undertaken to identify meta-analyses of randomised controlled trials (RCTs) of exercise in people with clinically diagnosed mental disorders. In the absence of available meta-analyses for a mental disorder, we identified systematic reviews of exercise interventions in people with elevated mental health symptoms that included non-RCTs. Meta-analysis quality was assessed with the AMSTAR/+.

RESULTS

Overall, we identified 27 systematic reviews (including 16 meta-analyses representing 152 RCTs). Among those with MDD, we found consistent evidence (meta-analyses = 8) that exercise reduced depression in children, adults and older adults. Evidence also indicates that exercise was more effective than control conditions in reducing anxiety symptoms (meta-analyses = 3), and as an adjunctive treatment for reducing positive and negative symptoms of schizophrenia (meta-analyses = 2). Regarding neurocognitive effects, exercise improved global cognition in schizophrenia (meta-analyses = 1), children with ADHD (meta-analyses = 1), but not in MDD (meta-analyses = 1). Among those with elevated symptoms, positive mental health benefits were observed for exercise in people with pre/post-natal depression, anorexia nervosa/bulimia nervosa, binge eating disorder, post-traumatic stress disorder and alcohol use disorders/substance use disorders. Adverse events were sparsely reported.

CONCLUSION

Our panoramic meta-overview suggests that exercise can be an effective adjunctive treatment for improving symptoms across a broad range of mental disorders.

Effectiveness of a brief lifestyle intervention targeting mental health staff: analysis of physical fitness and activity in the Keeping Our Staff in Mind study

BACKGROUND

People with mental illness die on average 15 years less than the general population, primarily to cardiometabolic disease. Lifestyle interventions are effective in reducing cardiometabolic risk but are not routinely provided to mental health consumers. Lifestyle interventions targeting mental health staff may be beneficial in changing culture surrounding physical health and subsequently improving consumer outcomes. This study examines exercise and fitness outcomes of a targeted lifestyle intervention directed at Australian mental health staff.

METHODS

A pragmatic single-arm intervention study was conducted within an Australian public mental health service. Mental health staff were provided a five-session individualised lifestyle intervention (incorporating exercise and nutritional counselling) over 5 weeks. Two waves of the programme were delivered between 2015 and 2016. This paper examines the exercise and fitness outcomes of the second wave of the study. Participants were assessed at baseline and at a 16-week follow-up. The primary exercise outcome was a measurement of cardiorespiratory fitness. Secondary outcomes included self-reported physical activity and a measurement of handgrip strength.

RESULTS

A total of 106 staff participated in this component of the study. Cardiorespiratory fitness increased significantly from baseline to follow-up (p<0.001). Significant improvements to physical activity occurred with decreases in sedentary time (p<0.0005) and increases in moderate-to-vigorous physical activity (p<0.005).

CONCLUSION

Lifestyle interventions incorporating exercise counselling may improve the physical health of mental health staff. Such strategies may be effective in improving culture surrounding physical health and/or increasing the effectiveness of lifestyle interventions targeting mental health consumers.

Identification of the brain networks that contribute to the interaction between physical function and working memory: An fMRI investigation with over 1,000 healthy adults

There is a growing consensus regarding the positive relationship between physical function and working memory; however, explanations of task-evoked functional activity regarding this relationship and its differences in physical function domains remain controversial. This study illustrates the cross-sectional relationships between cardiorespiratory fitness, gait speed, hand dexterity, and muscular strength with working memory task (N-back task) performance and the mediating effects of task-evoked functional activity in 1033 adults aged between 22 and 37 years. The results showed that cardiorespiratory fitness and hand dexterity were independently associated with N-back task performance to a greater extent and in contrast to gait speed and muscular strength. These relationships were mediated by task-evoked functional activity in a part of the frontoparietal network (FPN) and default mode network (DMN). Superior cardiorespiratory fitness could contribute to working memory performance by enhancing the compensational role of FPN-related broader region activation. Hand dexterity was associated with moderation of the interaction in terms of task-evoked activation between the FPN and DMN, which in turn, improved N-back task performance. Based on these findings, we conclude that cardiorespiratory fitness and hand dexterity have common and unique mechanisms enhancing working memory.

Handgrip Strength Is Associated With Hippocampal Volume and White Matter Hyperintensities in Major Depression and Healthy Controls: A UK Biobank Study

OBJECTIVE

Emerging evidence suggests that handgrip strength (a proxy for muscular fitness) is associated with better cognitive performance in people with major depressive disorder (MDD). The underlying processes are unclear, although hippocampal volume (HCV) reductions and white matter hyperintensities (WMHs) have been implicated. Therefore, we investigated the associations between handgrip strength and various brain region volumes and WMHs in MDD and healthy controls (HCs).

METHODS

This study is a cross-sectional analysis of handgrip strength and neuroimaging data from the UK Biobank. Generalized linear models were used to assess the relationship between grip strength and gray matter, white matter, total brain volume, left and right hippocampus volume, and WMHs in MDD and HCs, adjusting for age, sex, education, and body weight.

RESULTS

The sample included 527 people with MDD (54.3 ± 7.3 years, 37.2% male) and 1764 HCs (56.6 ± 7.2 years, 53% male). In MDD, stronger handgrip was significantly associated with increased left (coefficient ± SE = 108.1 ± 27.6, t = 3.92) and right (76.8 ± 30.4, t = 2.53) HCV. In HCs, only right HCV related to handgrip strength (44.8 ± 18.1, t = 2.47). Interaction analyses found stronger associations between grip strength and HCV in MDD compared with HCs, for both hippocampal regions. Stronger handgrip was associated with reduced WMHs in people with MDD (-0.24 ± 0.07, t = -3.24) and HCs (-0.11 ± 0.04, t = -2.47). Maximal handgrip strength was not associated with gray matter, white matter, or total brain volumes in either group.

CONCLUSIONS

Stronger grip strength is associated with greater left and right HCV and reduced WMHs in MDD. Future research should investigate directionality and consider if interventions targeting strength/muscular fitness can improve brain health and reduce the neurocognitive abnormalities associated with MDD.

The relationship between physical activity, clinical and cognitive characteristics and BDNF mRNA levels in patients with severe mental disorders

Background: Here we aimed to clarify the association of physical activity with cognitive function and current mood in severe mental disorders in the most extensive sample to date. Secondly, we aimed to investigate the relationship between physical activity and BDNF mRNA levels.Methods: Three hundred and six patients with a DSM-IV schizophrenia (SZ) or bipolar disorder (BD) spectrum diagnosis were included. Clinical characteristics were assessed using the Structured Clinical Interview for DSM-IV. Depressive symptomatology was measured using the Inventory of Depressive Symptoms (IDS-C) and the Calgary Depression Scale for Schizophrenia (CDSS). All patients underwent neuropsychological assessment. Physical activity was measured as hours spent on any regular physical activity (≥ or ˂90 min) per week. BDNF mRNA was measured in plasma using standardised procedures.Results: Patients with ≥90 min of physical activity per week had fewer depressive symptoms (P ˂0.001, Cohen's d = 0.48) and performed significantly better on working memory (P ˂ 0.001, d = 0.44) and executive functioning tasks (P ˂ 0.001, d = 0.50) compared to the ˂90-min group. BDNF mRNA was positively associated with physical activity (P = 0.046) and cognitive functioning (P = 0.037).Conclusions: Our study suggests a positive association between self-reported physical activity, cognitive function, mood and BDNF mRNA levels in severe mental disorders.

The evidence for physical activity in the management of major mental illnesses: a concise overview to inform busy clinicians' practice and guide policy

PURPOSE OF REVIEW

Physical activity has established the efficacy in improving physical health, mental health and cognition in the general population. Recent research has examined its potential as a preventive measure and/or adjunctive treatment for various mental health conditions. This review summarizes the recent evidence for physical activity in the management of major mental illnesses.

RECENT FINDINGS

Emerging evidence suggests that physical activity may confer protection against depression and anxiety/stress disorders. There is robust evidence that structured and supervised physical activity, including aerobic and resistance training, can improve multiple outcomes in major depression, pre/postnatal depression, anxiety/stress disorders and schizophrenia. Emerging evidence suggests a potential role for physical activity in bipolar disorder and alcohol use disorders.

SUMMARY

The quantity and quality of evidence regarding the efficacy of physical activity for mental illnesses is increasing. Given the established and further potential benefits and low adverse risk profile, physical activity should be offered as an adjunctive part of core mental health treatment. However, there is a need for high-quality multisite randomized controlled trials that can be replicated in routine care in mental health services. Future population-level trials are needed to examine the potential use of physical activity in those at risk of mental health conditions to see if physical activity can prevent the development of mental disorders.

Associations between grip strength and generalized anxiety disorder in older adults: Results from the Irish longitudinal study on ageing

BACKGROUND

Associations between grip strength and mental health disorders have been established; however, associations between grip strength and Generalized Anxiety Disorder (GAD) remain unstudied. Therefore, this study investigates associations between grip strength and prevalent and incident GAD.

METHODS

A prospective cohort design was utilized. At baseline, participants aged ≥50 years (N = 3,952) completed a hand grip strength assessment and abbreviated Penn State Worry Questionnaire (PSWQ) and were divided into sex-specific tertiles based on strength. A score of ≥23 on the PSWQ defined caseness of GAD. At two-year follow-up, GAD was assessed with the Composite International Diagnostic Interview-Short Form.

RESULTS

Prevalence and incidence of GAD were 18.2% (N = 718) and 0.9% (N = 29), respectively. Adjusting for age, sex, waist circumference, social class, smoking status, and physical activity, a one-standard-deviation (1-SD) increase in strength was associated (OR, 95%CI) with 12.1% (OR = 0.88, 0.80-0.96; p < 0.01) lower odds of prevalent GAD, and middle and high strength tertiles were associated with 27.3% (OR = 0.73, 0.59-0.89; p < 0.01) and 23.1% (OR = 0.77, 0.62-0.95; p < 0.05) lower odds, respectively. A 1-SD increase in strength was non-significantly associated with 24.2% (OR = 0.76, 0.50-1.14) lower odds of incident GAD, and middle and high strength tertiles were non-significantly associated with 31.4% (OR = 0.69, 0.30-1.58) and 66.5% (OR = 0.34, 0.11-1.00) lower odds, respectively (all p > 0.05). There was no significant interaction between strength tertiles and sex.

LIMITATIONS

The observational nature of the study limits inferring causality.

CONCLUSIONS

Increased hand grip strength may be associated with lower odds of developing GAD in older adults. Larger investigations of prospective associations are needed.

Functional and/or structural brain changes in response to resistance exercises and resistance training lead to cognitive improvements - a systematic review

BACKGROUND

During the aging process, physical capabilities (e.g., muscular strength) and cognitive functions (e.g., memory) gradually decrease. Regarding cognitive functions, substantial functional (e.g., compensatory brain activity) and structural changes (e.g., shrinking of the hippocampus) in the brain cause this decline. Notably, growing evidence points towards a relationship between cognition and measures of muscular strength and muscle mass. Based on this emerging evidence, resistance exercises and/or resistance training, which contributes to the preservation and augmentation of muscular strength and muscle mass, may trigger beneficial neurobiological processes and could be crucial for healthy aging that includes preservation of the brain and cognition. Compared with the multitude of studies that have investigated the influence of endurance exercises and/or endurance training on cognitive performance and brain structure, considerably less work has focused on the effects of resistance exercises and/or resistance training. While the available evidence regarding resistance exercise-induced changes in cognitive functions is pooled, the underlying neurobiological processes, such as functional and structural brain changes, have yet to be summarized. Hence, the purpose of this systematic review is to provide an overview of resistance exercise-induced functional and/or structural brain changes that are related to cognitive functions.

METHODS AND RESULTS

A systematic literature search was conducted by two independent researchers across six electronic databases; 5957 records were returned, of which 18 were considered relevant and were analyzed.

SHORT CONCLUSION

Based on our analyses, resistance exercises and resistance training evoked substantial functional brain changes, especially in the frontal lobe, which were accompanied by improvements in executive functions. Furthermore, resistance training led to lower white matter atrophy and smaller white matter lesion volumes. However, based on the relatively small number of studies available, the findings should be interpreted cautiously. Hence, future studies are required to investigate the underlying neurobiological mechanisms and to verify whether the positive findings can be confirmed and transferred to other needy cohorts, such as older adults with dementia, sarcopenia and/or dynapenia.

The association of grip strength with depressive symptoms and cortisol in hair: A cross-sectional study of older adults

BACKGROUND

Low handgrip strength has been shown to be associated with higher levels of depressive symptoms. One area of mental health that is understudied in relation to grip strength is chronic stress, which can exist independently to depression, or as a comorbidity or precursor to this condition. The present study examined cross-sectional associations between grip strength, an established marker of physical function, and (a) depressive symptoms and (b) chronic stress utilizing hair cortisol concentrations, while accounting for multiple pertinent confounding variables.

METHOD

Data were used from wave 6 (2012/13) of the English Longitudinal Study of Aging, a panel study of older (≥50 years) community-dwelling men and women. Grip strength was measured in kg using a hand-held dynamometer. Depressive symptoms were assessed using the 8-item Center for Epidemiologic Studies Depression scale. Hair cortisol concentrations (pg/mg) were determined from samples of scalp hair and log-transformed for analysis to correct skewness. Associations of grip strength with depressive symptoms and hair cortisol concentration were tested using linear regression models adjusted for age, sex, ethnicity, wealth, smoking status, physical activity, body mass index, limiting long-standing illness, arthritis, diabetes, and hair treatment.

RESULTS

The sample comprised of 3741 participants (mean age 68.4 years, 66.4% female). After adjustment for age and sex, grip strength was significantly and negatively associated with both depressive symptoms (B = -0.038, SE = 0.004, P < 0.001) and hair cortisol (B = -0.003, SE = 0.001, P = 0.029). However, in the fully-adjusted models, both associations were attenuated and only the association with depressive symptoms remained statistically significant (B = -0.015, SE = 0.004, P < 0.001; hair cortisol B = -0.002, SE = 0.001, P = 0.088).

CONCLUSION

In a large sample of older adults in England, grip strength was negatively associated with depressive symptoms. Results were inconclusive regarding the association between grip strength and chronic stress. Further research examining the longitudinal relationships between muscular strength and specific aspects of mental health, while also exploring the neurobiological mechanisms underlying these associations, is warranted before recommendations for policy and practice can be made.