Association between obesity, physical activity, and cognitive decline in Chinese middle and old-aged adults: a mediation analysis

Association of birth weight, midlife obesity, and transition patterns with mild cognitive impairment and brain MRI indices: A prospective population-based study

BACKGROUND

To evaluate associations of birth weight, midlife weight, and their transitions with mild cognitive impairment (MCI) and brain MRI indices.

METHODS

This prospective cohort study included 200,726 UK Biobank participants. Self-reported birth weight and measured midlife anthropometrics were used to classify obesity (waist circumference [WC]/waist-to-hip ratio [WHR]). We constructed nine weight transition patterns from birth to midlife WC, six from birth to midlife WHR. Cox proportional hazards models and linear regression models were used to examine associations of birth weight, midlife body size and their transitions with MCI and brain MRI indices.

RESULTS

Compared to normal birth weight, low birth weight (HR: 1.29, 95 % CI: 1.16-1.44) and high birth weight (1.11, 1.01-1.22) were both associated with increased risk of MCI, showing a U-shaped relationship. Compared to normal weight at midlife, midlife central obesity [WC (1.25, 1.15-1.37) and WHR (1.27, 1.17-1.37)] were significantly associated with elevated MCI risk. Compared to individuals with normal weight at birth and midlife, those with low birth weight who transition to central obesity at midlife, defined by WC (1.51, 1.27-1.78) or WHR (1.42, 1.22-1.66), showed the highest risk of MCI. Weight transitions were also associated with brain structure, individuals who had low or high birth weight and developed midlife obesity showed significant reductions in total brain volume and grey matter volume, as well as increases in white matter hyperintensity volume.

CONCLUSIONS

Birth weight exhibited a U-shaped association with MCI risk. Individuals transitioning from low birth weight to midlife central obesity demonstrated the highest MCI susceptibility.

Longitudinal Trajectories of Cognitive Function Among Chinese Middle-Aged and Older Adults: The Role of Sarcopenia and Depressive Symptoms

Objectives: The longitudinal relationship between sarcopenia, depression, and cognitive impairment has been insufficiently studied in China. This study aimed to characterize the association between sarcopenia and cognitive impairment and the mediating role of depression using nationally representative data. Methods: 7091 middle-aged and older adults were analyzed from the China Health and Retirement Longitudinal Study (CHARLS) across three waves (2011, 2013, and 2015). Cognitive trajectories were modeled using a group-based trajectory model (GBTM), while multivariable ordinal logistic regression was employed to evaluate the associations with cognitive trajectories. The mediating role of depressive symptoms was assessed through bootstrap mediation analysis and cross-lagged panel modeling (CLPM). Results: Trajectory analysis identified four distinct cognitive function patterns: "High and Stable" trajectory (n = 2563, 36.73%), "Middle and Stable" group (n = 2860, 38.76%), "Middle and Decline" group (n = 1280, 18.62%), and "Low and Decline" group (n = 388, 5.90%). Sarcopenia and depressive symptoms were associated with the "Low and Decline" trajectory of cognitive function [Overall: OR (95%CI) of 0.315 (0.259, 0.382) and 0.417 (0.380, 0.459)]. Mediation analysis indicated that depressive symptoms accounted for 11.78% of the relationship between sarcopenia and cognitive trajectories. The cross-lagged panel modeling demonstrated a significant mediation pathway of "T1 cognitive function → T2 depression → T3 sarcopenia", with T2 depression mediating 5.31% of the total effect. Conclusions: Our study identified four distinct cognitive trajectories, with sarcopenia and depressive symptoms significantly associated with worse cognitive trajectories over time. Depressive symptoms mediated the relationship between sarcopenia and cognitive function. This highlights the importance of integrating mental health and physical health interventions to address the interconnected risks associated with aging.

Association between abdominal obesity and cognitive decline among Chinese middle-aged and older adults: a 10-year follow-up from CHARLS

Introduction

The relationship between abdominal obesity and cognitive decline has controversial results, and the mediating effect of high-density lipoprotein cholesterol (HDL-C) between them remains uncertain. This study aims to explore the association between abdominal obesity and cognitive decline in middle-aged and older adults, including dose-response relationship and age differences, as well as the mediating effect of HDL-C.

Methods

Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS), involving 3,807 participants aged 45 and above from 2010 to 2020. The TICS-10 was used to assess cognitive function, and the group-based trajectory model (GBTM) was used to explore the potential heterogeneity of cognitive changes. Abdominal obesity was measured by baseline waist circumference (WC) and a sequentially adjusted unordered multinomial logistic regression was used to investigate the association between abdominal obesity and cognitive decline in middle-aged and older adults. Restricted cubic spline (RCS) model was adopted to analyze the dose-response relationship between WC and risk of cognitive decline. HDL-C was used as a mediator to examine the potential causal chain between abdominal obesity and cognitive decline.

Results

Among the 3,807 participants, a total of 1,631 individuals (42.84%) had abdominal obesity. The GBTM identified 3 cognitive function trajectories: rapid decline (11.0%), slow decline (41.1%) and stable groups (47.9%). After controlling for confounders, participants with abdominal obesity were less likely to experience rapid decline (OR: 0.67, 95%CI: 0.51-0.8) and slow decline (OR: 0.81, 95%CI: 0.69-0.95) of cognitive function, compared to those with normal WC. RCS analysis showed a decreased risk of cognitive decline with increasing WC. In the age subgroup analysis, the protective effect was significant only in the population aged 50 and above. HDL-C mediated 19.15% (P < 0.05) of the relationship between abdominal obesity and cognitive decline.

Conclusion

Abdominal obesity had a significant protective effect on cognitive decline in Chinese middle-aged and older adults, with HDL-C playing a mediating role in the relationship between abdominal obesity and cognitive decline.

Longitudinal associations between pain and cognitive decline in middle-aged and older Chinese adults: the mediating role of depressive symptoms

Objective

The primary aim of this scholarly investigation was to elucidate the correlation between Number of Pain Sites and cognitive decline within the older adult population. Additionally, the study sought to examine the potential mediating influence of depressive symptoms in moderating the association between pain and cognitive deterioration.

Methods

We analyzed 8,835 participants aged 45 and above, with data collected from 2011 to 2018. Participants were categorized into two groups-stable and rapidly declining cognitive function-using the KML3D clustering method. Binary logistic regression analysis was conducted to examine the association between pain status, depressive symptoms, and cognitive trajectories, and mediation analysis was used to assess the mediating role of depression.

Results

Multi-site pain was significantly associated with the risk of rapid cognitive decline (adjusted OR = 1.30, 95% CI: 1.14-1.48), and depressive symptoms were also a significant predictor of rapid cognitive decline (adjusted OR = 1.49, 95% CI: 1.32-1.68). Mediation analysis revealed that depression mediated the effect of pain on cognitive decline, accounting for 25.71% of the total effect.

Conclusion

Our study establishes a significant longitudinal link between Number of Pain Sites and cognitive decline, mediated in part by depressive symptoms. This finding underscores the need for interventions that address pain and depression to potentially decelerate cognitive decline in older adults.

Status Quo of Mental Health and Influencing Factors Among Older Adults in Different Living Situations: A Random Forest Analysis Based on CHARLS Data

PURPOSE

To determine the status of depression and its key influencing factors among Chinese older adults in different living situations.

METHOD

Data of 7,092 older adults were obtained from the China Health and Retirement Longitudinal Survey. This study analyzed key variables influencing depressive symptoms using random forest modeling and logistic regression.

RESULTS

The prevalence of depressive symptoms in older adults is 33.2%, with the highest prevalence of depression in older adults living alone (41.2%). Cognitive functioning and life satisfaction are psychological factors that affect older adults' mental health, whereas self-rated health and child relationship satisfaction are biological and social factors affecting their mental health, respectively. Furthermore, self-rated pain and limitations in activities of daily living were identified as risk factors for their mental health. Key factors affecting older adults' mental health differ between living situations.

CONCLUSION

Key factors of depressive symptoms in older adults differ across living situations, providing a priority and reference for differential prevention and precise intervention of depressive symptoms to promote a healthy aging process. Results of the current study may help clinicians better understand the pathogenesis of depression in older adults, guide clinical diagnosis and treatment, and develop individualized depression prevention and management strategies. [Research in Gerontological Nursing, 18(2), 91-98.].

Association Between BMI and Neurocognitive Functions Among Middle-aged Obese Adults: Preliminary Findings Using Machine-learning (ML)-based Approach

Background

Studies suggest that obesity predisposes individuals to developing cognitive dysfunction and an increased risk of dementia, but the nature of the relationship remains largely unexplored for better prognostic predictors.

Purpose

This study, the first of its kind in Indian participants with obesity, was intended to explore the use of quantification of different neurocognitive indices with increasing body mass index (BMI) among middle-aged participants with obesity. Additionally, machine-learning models were used to analyse the predictive performance of BMI for different cognitive functions.

Methods

In the cross-sectional analytical study, a total of 137 (n = 137) participants were included. Out of the total, 107 healthy obese (BMI = 23.0-30.0 kg m-2; age between 36 and 55 years of both genders) were recruited from the out-patient department of the Department of Endocrinology and General Medicine, and 30 participants were recruited as the control group, between March 2023 to February 2024. The participants underwent neuropsychological assessments, including mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA) and serum levels of brain-derived neurotrophic factor (BDNF).

Results

Significant (p < .05) differences were observed for neurocognitive functions for the obese group versus the control group. According to the correlation heatmaps, BMI was significantly (p < .05) negatively associated with BDNF. Multivariate linear regression analysis revealed a substantial (p < .05) decline in BDNF with a change in BMI, accenting its significant impact on cognitive ageing. Additionally, consistent decreasing trends were observed across the MoCA and MMSE, confirming the robustness of the findings across diverse analytical methodologies. Furthermore, the linear regression model and super vector machine model contributed additional evidence to the consistency of the trends in cognitive decline linked to BMI variations.

Conclusion

The preliminary results of the present study support that increased BMI is an important physiological indicator that influences neurocognition and neuroplasticity in individuals with obesity.

The Effect of Physical Activity Interventions on Executive Function in Overweight and Obese Adults: A Systematic Review

Background/objectives: Overweight and obesity are global public health problems associated with chronic disease and mental health. Physical activity (PA) is essential throughout a person's life; an active lifestyle helps people to live healthier lives and improve their functional and mental abilities, such as executive function (EF). This systematic review aimed to analyze the evidence on the effects of PA on EF in overweight and/or obese adults (≥18 years old). Methods: Records from the PubMed, ScienceDirect, and JSTOR databases were searched and, following the PRISMA guidelines, seven studies were included in the present systematic review. Risk of bias was assessed using the National Institute of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Results from the studies included indicate that acute, short-term, and long-term PA interventions are an effective strategy to improve inhibitory control, working memory, and processing speed in overweight and obese adults. Furthermore, evidence indicates that EF can be effective as a measure to predict adherence to PA programs and weight loss. Conclusions: Exercise and physical activity interventions are a promising therapeutic strategy to promote weight loss and improve EF in adults with overweight and obesity. Additionally, EF may be further explored as a predictor of healthy aging due to the choices made throughout life and the long-term benefits that result.

Body mass index, waist circumference, hip circumference, abdominal volume index, and cognitive function in older Chinese people: a nationwide study

BACKGROUND

Numerous studies have indicated an obesity paradox in observational research on aging health, where being normal weight or underweight adversely affects cognitive function, while moderate obesity may offer protective benefits. This study aims to investigate the association between body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), abdominal volume index (AVI), and the joint effect of BMI and HC on cognitive impairment in older Chinese people.

METHODS

A total of 10,579 participants aged 65 years and older from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS) were included in this cross-sectional study. BMI, WC, HC, WHtR, WHR, and AVI were calculated from height, weight, WC, and HC measurements, where weight, WC, and HC were obtained by direct measurement. Mini-Mental State Examination was used to assess cognitive impairment. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated using binary logistic regression. Non-linear correlations were investigated using restricted cubic spline curves.

RESULTS

In multivariate logistic regression models fully adjusted for confounding variables, our analyses showed significant negative associations of WC [OR 0.93 (95%CI 0.88-0.98), P = .012], HC [OR 0.92 (95%CI 0.87-0.97), P = .004], lower WHR (Q2) [OR 0.85 (95%CI 0.72-1.00), P = .044], and AVI [OR 0.93 (95%CI 0.88-0.98), P = .011] with cognitive impairment. Nonlinear curve analysis showed that the risk of cognitive impairment was lowest when the BMI was about 25.5 kg/m², suggesting that the optimal BMI for older Chinese people to maintain good cognitive ability may be in the overweight range. In addition, there was a non-linear "N" shaped relationship between HC and cognitive impairment, with HC having the highest risk of cognitive impairment at about 82 cm and the lowest risk at about 101 cm. The joint effects analysis indicated that the lowest risk was observed among those with normal or higher BMI but higher HC compared with participants with normal BMI levels and lower HC levels.

CONCLUSION

In older Chinese people, a low-waisted and high-hip circumference body figure is favorable for cognitive function in older people. It also found a significant association between AVI and cognitive impairment. The joint analysis of BMI and HC suggests that maintaining a normal or higher BMI with a higher HC may be more conducive to maintaining good cognitive function.

Effects of single- and double-shift work on hand and cognitive functions in nurses

AIM

This study aims to examine the influence of single and double-shift work schedules on hand function and cognitive capacities, specifically working memory, attention, and response time in nurses.

BACKGROUND

Shift work, particularly in extended formats, is known to affect various physical and cognitive functions critical to nursing duties. Understanding these impacts is vital for managing nurse schedules to minimize health risks and maximize performance.

INTRODUCTION

With an increase in demands on healthcare systems, nurses often endure prolonged working hours, which may impair their cognitive and manual abilities, thereby affecting patient care quality.

METHODS

This study involved 45 nurses aged 20-40 years from shift-oriented units providing direct patient care. Hand function was assessed using the Nine-Hole Peg Test (9-HPT). Cognitive functions such as working memory, attention, and response time were evaluated using the digit span task and the Stroop test, respectively. Two-way analysis of variance (ANOVA) was used for statistical analysis, assessing the interactions of time and shift type, with a significance level set at p < 0.05.

RESULTS OR FINDINGS

The results revealed significant changes in all tested variables between pre- and post-shift assessments and between single and double-shift conditions. Notably, the double-shift work significantly exacerbated declines in all measured functions.

DISCUSSION

These findings suggest that double shifts may intensify the deterioration of essential nursing skills, potentially compromising patient care.

CONCLUSION AND IMPLICATIONS FOR NURSING AND/OR HEALTH POLICY

This study underscores the detrimental effects of extended shift work on nurses' cognitive and manual functions. These insights should guide healthcare institutions in revising nurse scheduling practices to safeguard their well-being and maintain high standards of patient care.

Association of cognitive performance with overall, dosage, intensity, and domain physical activity in aging: NHANES 2011-2014

BACKGROUND

The specific relationship between PA in detailed types and cognition is still unclear due to limited evidence. Our study aimed to investigate the relationship between cognitive performance and various aspects of physical activity, including overall activity, dosage, intensity levels [moderate physical activity (MPA), vigorous PA], and different domains of activity [occupational PA (OPA), transportation PA (TPA), and leisure-time PA (LTPA)] in older adults using data from the NHANES database.

METHODS

This cross-sectional analysis used data from 2 cycles of NHANES (2011-2014). PA was determined through participants' self-reports using the Global Physical Activity Questionnaire (GPAQ). Cognitive performance was evaluated by the presence of psychometric mild cognitive impairment (p-MCI), identified based on a composite measure derived from three cognitive tests including the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), the Animal Fluency test, and the Digit Symbol Substitution test (DSST). Logistic regression models were used to evaluate the association.

RESULTS

A total of 2588 participants aged 60 years or older were included, with an average age of 69.4 years and 48% being male. In the fully adjusted model, compared to no PA, performing 300 min of PA, and MPA were associated with 44%, and 33% reductions in the prevalence of p-MCI, respectively. Additionally, engaging in 1-149 min/week [OR 0.56, 95% CI (0.33-0.92)] and ≥ 300 min/week [OR 0.66, 95% CI (0.44-0.96)] of OPA, as well as ≥ 300 min/week [OR 0.56, 95% CI (0.36-0.86)] of LTPA, were also associated with a lower prevalence of p-MCI. Additionally, engaging in a diverse range of PA had better outcomes.

CONCLUSIONS

Our results suggested a positive association between higher levels of PA and enhanced cognitive performance. Different intensities and domains of PA have varying impacts on cognition. Future exploration, such as objectively measured PA and longitudinal studies were needed to validate our conclusion.

Dual group-based trajectories of physical activity and cognitive function in aged over 55: a nationally representative cohort study

Background

As individuals age, they commonly experience reduced physical activity and cognitive decline. While evidence, there is limited trajectory research on their concurrent progression and interrelation in individuals over 55 years old.

Methods

The data was collected from 5,765 individuals aged over 55 years who participated in the China Health and Retirement Longitudinal Study (CHARLS) between 2011 and 2020. Physical activity was measured by IPAQ, cognitive function by episodic memory, and mental intactness score. Separate sets of group-based trajectory models were fitted to identify physical activity trajectories and cognitive function trajectories. Multivariate logistic regression was used to estimate the association between baseline characteristics and each set of trajectories. Group-based dual trajectory modeling (GBDTM) was applied to quantify these associations.

Results

GBDTM identified three distinct trajectory groups for physical activity and cognitive outcomes. The physical activity trajectories were classified as "Persistently low physical activity" (74.2%), "Decreasing physical activity" (13.7%), and "Rising physical activity" (12.1%). Similarly, cognitive function trajectories were categorized as "Persistently low cognitive function" (22.2%), "Persistently moderate cognitive function" (37.9%), and "Persistently high cognitive function" (39.9%). Notably, 15.6% of participants followed the trajectories of "Persistently low physical activity" and "Persistently low cognitive function." The presence of a severe decline in physical activity was associated with an increased likelihood of poor cognitive function and vice versa. Age, sex, education, residential status, BMI, and visual impairment were identified as significant predictors for physical activity and cognitive decline.

Conclusion

This study found that the GBDTM can determine the consistent trajectories of physical activity and cognitive function trajectories that persistently decline in individuals over 55 years. Analyses of predictive factors can be instrumental in promoting physical activity and delaying cognitive decline.

Subjective Cognitive Impairment and Physical Activity: Investigating Risk Factors and Correlations among Older Adults in Spain

Subjective cognitive impairment in older persons has a substantial influence on their quality of life and can progress to serious illnesses such as dementia. Physical activity level can help prevent cognitive decline and improve cognitive performance. The aim of this study was to investigate the association between frequency of physical activity and subjective cognitive impairment in Spanish adults aged 65 and over, and to identify different risk factors. Using data from the EHSS20 survey, the study focused on 7082 participants who provided information on cognitive impairment and physical activity. Key predictor variables included age, gender, BMI, marital status, and education level. A significant relationship was found between BMI category and gender, with 66.5% of the population being overweight or obese. Men were more likely to be overweight than women. Socio-demographic factors such as educational level, marital status, and physical activity frequency showed dependent associations with sex. Women had a higher prevalence of subjective cognitive impairment than men. A strong association was found between frequency of physical activity and subjective cognitive impairment, with inactive older people having the highest prevalence of subjective cognitive impairment. Older women who engage in little physical exercise and have less education are at risk for subjective cognitive impairment. Furthermore, for both men and women, being overweight was associated with a more reduced risk than obesity. Significant relationships were also discovered between subjective cognitive impairment, frequency of physical exercise, gender, BMI, and degree of education. In conclusion, older, sedentary women with high BMI and less education are more likely to experience subjective cognitive impairment.

Triglyceride-glucose index in the prediction of new-onset arthritis in the general population aged over 45: the first longitudinal evidence from CHARLS

OBJECTIVE

Insulin resistance (IR) imposes a significant burden on inflammatory diseases, and the triglyceride-glucose (TyG) index, which is an easily accessible indicator for detecting IR, holds great application potential in predicting the risk of arthritis. The aim of this study is to analyze the association between the TyG index and the risk of new-onset arthritis in the common population aged over 45 using a prospective cohort study design.

METHOD

This population-based cohort study involved 4418 participants from the China Health and Retirement Longitudinal Study (from Wave 1 to Wave 4). Multivariate logistic regression models were employed to investigate the association between the TyG index and new-onset arthritis, and RCS analyses were used to investigate potential non-linear relationships. Moreover, decision trees were utilized to identify high-risk populations for incident arthritis.

RESULT

Throughout a 7-year follow-up interval, it was found that 396 participants (8.96%) developed arthritis. The last TyG index quartile group (Q4) presented the highest risk of arthritis (OR, 1.39; 95% CI, 1.01, 1.91). No dose-response relationship between the TyG index and new-onset arthritis was identified (Poverall=0.068, Pnon-linear=0.203). In the stratified analysis, we observed BMI ranging from 18.5 to 24 exhibited a heightened susceptibility to the adverse effects of the TyG index on the risk of developing arthritis (P for interaction = 0.035).

CONCLUSION

The TyG index can be used as an independent risk indicator for predicting the start of new-onset arthritis within individuals aged 45 and above within the general population. Improving glucose and lipid metabolism, along with insulin resistance, may play a big part in improving the primary prevention of arthritis.