Between-person and within-person effects in the temporal relationship between depressive symptoms and cognitive function

A longitudinal study of the mediator role of physical activity in the bidirectional relationships of cognitive function and specific dimensions of depressive symptoms

BACKGROUND

The bidirectional relationship between cognitive function and depressive symptoms has been extensively reported. However, the potential mechanisms are still not clear. We aim to longitudinally investigate whether physical activity mediates the bidirectional relationships between cognitive function and specific dimensions of depressive symptoms.

METHODS

Data from 6,787 individuals aged ≥50 of 2014/15 (T1), 2016/17 (T2), and 2018/19 (T3) waves of the English Longitudinal Study of Ageing (ELSA). Cognitive function was assessed by domains of memory, orientation in time, and executive function. Physical activity was measured with the intensity and frequency of participation. Specific dimensions of depressive symptoms were assessed by the 8-item Center for Epidemiologic Studies Depression Scale, distinguishing between cognitive-affective and somatic symptoms. Cross-lagged panel models were used to investigate the mediating role of physical activity in the bidirectional relationships between cognitive function and two dimensions of depressive symptoms.

RESULTS

Poorer cognitive function was indirectly associated with worse cognitive-affective symptoms (indirect effect = -0.002, 95%CI: -0.004, -0.001) through lower physical activity levels. Poorer cognitive function was also indirectly associated with worse somatic symptoms (indirect effect = -0.003, 95%CI: -0.006, -0.002) through lower physical activity levels, and the reverse mediation was observed as well (indirect effect = -0.002, 95%CI: -0.004, -0.001).

LIMITATIONS

There is no distinction between potential within-person and between-person effects.

CONCLUSIONS

Collaborative interventions of physical activity are beneficial in protecting cognitive function and mental health in older adults.

Association between cognitive function and depressive symptoms in Chinese older adults: The mediating role of activities of daily living

OBJECTIVES

Exploring the relationship between cognitive functioning and depressive symptoms in Chinese older adults and the mediating role of the ability to perform activities of daily living.

METHODS

This study included 5775 older adults, and correlation analysis and linear regression were used to analyze the relationship between the variables and mediated effects.

RESULTS

Cognitive functioning and the ability to perform daily living significantly influenced the depressive state (β = -0.163, p < 0.01; β = 0.288, p < 0.01), and the ability to perform daily living partially mediated the effect between the two, with an effect size of 27.95%.

CONCLUSION

Cognitive function can influence depressive status through the ability to perform activities of daily living, and individualized intervention strategies should be developed for older adults to maintain or delay cognitive decline, preserve the ability to perform activities of daily living, and reduce the risk of depression.

A multimodal group-based immersive virtual reality intervention for improving cognition and mental health in patients with post-covid-19 condition. A quasi-experimental design study

Introduction

Adults with Post-COVID-19 Condition (PCC) may show cognitive impairments in attention, processing speed, memory, and executive function. Multimodal programs that combine cognitive training, physical activity and emotional tasks, such as mindfulness-based interventions (MBIs), may offer a suitable alternative for improving PCC treatments. Immersive Virtual Reality (IVR) is a promising technology that can enhance traditional cognitive training, physical activity, and MBIs. The use of IVR technology may increase engagement with these interventions and potentially enhance the individual benefits of cognitive training, exercise and MBIs. The current study evaluated the impact of a multimodal IVR intervention, comparing this with a usual care intervention (control group), in order to assess changes in cognition and mental health in adults with PCC. We also aimed to assess user experience factors such as enjoyment, perceived improvement, and fatigue following each multimodal IVR session within the experimental group.

Method

Thirty-one participants with PCC symptoms were assigned to either the experimental group (IVR, n = 15) or the control group (usual care intervention, n = 16) in a quasi-experimental design study. The multimodal IVR intervention consisted of MBI, cognitive training and physical exercise and was delivered in a 60-min group session with 5 participants, twice a week, for 8 weeks (16 sessions in total). Measures of global cognition, attention, processing speed, verbal episodic memory and subjective memory complaints (primary measures), and depressive and anxiety symptoms and fatigue (secondary measures) were assessed at baseline and also after 8 weeks (post-intervention).

Results

Mixed between-group (group) and within-group (pre-post assessments) ANOVAs revealed significant group*time interactions in global cognition, simple attention, processing speed, memory and depressive symptoms, with large effect sizes (p < 0.05; partial η2 > 0.14). There was also a marginally significant group*time interaction for executive function (p = 0.05). Follow-up analyses comparing pre-and post-intervention outcomes for each group separately showed that the experimental group significantly improved in global cognition, processing speed, memory and depressive symptoms, while the control group showed no significant pre-post changes. Friedman tests showed a significant main effect of time (χ2(2) = 6.609, p = 0.04), with a gradual increase in enjoyment from the first, to the mid, and then to the final session. In addition, perceived improvement scores remained high throughout the intervention, and patient-reported fatigue levels did not fluctuate significantly throughout the intervention.

Conclusion

To our knowledge, no previous research has combined cognitive training, physical exercise and MBI using an IVR paradigm in adults with PCC. Despite their inherent limitations, our findings mark a pioneering step toward improving cognition and mental health outcomes in PCC through the innovative use of new technology and multimodal approaches. This first study should be accompanied by more extensive, randomized clinical trials aimed at further exploring and refining these interventions.

Internet use, physical activity and depressive symptoms in older adults: A cross-lagged panel analysis

BACKGROUND

Existing cross-sectional studies suggest a strong positive association between Internet use, physical activity, and mental health in older adults; however, longitudinal studies reporting the relationship between Internet use, physical activity, and levels of depressive symptoms in older adults are lacking. This study aimed to examine the bidirectional relationship between Internet use and depressive symptoms in older adults and its underlying mechanisms.

METHODS

We used two waves of follow-up data (2016 and 2018) from the China Family Panel Studies, including 5837 participants aged 60 years or above. The bidirectional relationship between Internet usage time and depressive symptoms was examined using a cross-lagged model. The mediating role of physical exercise was examined using a half-longitudinal mediation model.

RESULTS

The results revealed a bidirectional relationship between Internet use time, frequency of physical activity, and depressive symptoms. Longer Internet use predicted lower levels of depressive symptoms, and the frequency of physical activity mediated the longitudinal relationship between Internet use and depressive symptoms in older adults.

LIMITATIONS

First, our study used self-report-based variables. Second, our study did not obtain the specific timing of the application of various functions of the Internet and the intensity of physical activity among older adults. Finally, based on the availability of data, our study involved only two waves of data. This may not be sufficient for a full longitudinal mediation effect test.

CONCLUSIONS

Internet use and depressive symptoms were interrelated over time among older adults. The frequency of physical activity was a mediator of Internet use and depressive symptoms. This underscores the importance of Internet-based technologies to enable healthy living and prevent depression and loneliness in older adults.

Longitudinal relationships between depressive symptoms and cognitive function after stroke: A cross-lagged panel design

OBJECTIVE

Stroke is a leading cause of mortality and disability. This study aimed to investigate the temporal and directional relationships between post-stroke depressive symptoms and cognitive impairment using a cross-lagged panel design. Depressive symptoms and cognitive impairment are two common post-stroke complications. However, the precise underlying mechanism remains unclear despite their close relationship. Therefore, elucidating the causal relationship between these two issues is of great clinical significance for improving the poor prognosis of stroke.

METHODS

This study employed a hospital-based multicenter prospective cohort design. A total of 610 patients with ischemic stroke were eligible. Depressive symptoms (measured using the seventeen-item Hamilton Rating Scale for Depression) and cognitive function (measured using the Montreal Cognitive Assessment) were assessed at baseline and the 12-month follow-up. Spearman's correlation was used to examine the correlation between cognitive function and depressive symptoms. Additionally, a cross-lagged panel analysis was employed to elucidate the causal relationship between these factors after adjusting for potential covariates.

RESULTS

The results of a four-iteration cross-lagged panel analysis substantiated a bidirectional relationship between post-stroke depressive symptoms and cognitive function over time. Specifically, higher scores for early depressive symptoms were associated with lower scores for later cognitive function; additionally, higher baseline cognitive function scores were associated with lower depressive symptom scores at a later point.

CONCLUSION

This study establishes a reciprocally causal long-term relationship between depressive symptoms and cognitive function after an ischemic stroke. Therefore, interventions aimed at improving cognitive function and ameliorating depressive symptoms may positively affect both cognition and mood.

TRIAL REGISTRATION

ChiCTR-ROC-17013993.