Vascular risk factors, white matter microstructure, and depressive symptoms: a longitudinal analysis in the UK Biobank.

BACKGROUND: Cumulative burden from vascular risk factors (VRFs) has been associated with an increased risk of depressive symptoms in mid- and later life. It has been hypothesised that this association arises because VRFs disconnect fronto-subcortical white matter tracts involved in mood regulation, which puts older adults at higher risk of developing depressive symptoms. However, evidence for the hypothesis that disconnection of white matter tracts underlies the association between VRF burden and depressive symptoms from longitudinal studies is scarce. METHODS: This preregistered study analysed longitudinal data from 6,964 middle-aged and older adults from the UK Biobank who participated in consecutive assessments of VRFs, brain imaging, and depressive symptoms. Using mediation modelling, we directly tested to what extend white matter microstructure mediates the longitudinal association between VRF burden and depressive symptoms. RESULTS: VRF burden showed a small association with depressive symptoms at follow-up. However, there was no evidence that fractional anisotropy (FA) of white matter tracts mediated this association. Additional analyses also yielded no mediating effects using alternative operationalisations of VRF burden, mean diffusivity (MD) of single tracts, or overall average of tract-based white matter microstructure (global FA, global MD, white matter hyperintensity volume). CONCLUSIONS: Our results lend no support to the hypothesis that disconnection of white matter tracts underlies the association between VRF burden and depressive symptoms, while highlighting the relevance of using longitudinal data to directly test pathways linking vascular and mental health.

Multisensory flavor perception: The relationship between congruency, pleasantness, and odor referral to the mouth.

Our hedonic response to a food is determined by its flavor, an inherently multisensory experience that extends beyond the mere addition of its odor and taste. While congruency is known to be important for multisensory processes in general, little is known about its specific role in flavor processing. The aim of the present study was to delineate the effects of odor-taste congruency on two central aspects of flavor: odor referral (or mislocalization) to the mouth, and pleasantness. We further aimed to test whether an eventual effect on pleasantness was mediated by odor referral. Aqueous solutions containing odors and tastes were prepared to create food-like stimuli with varying degrees of congruency, ranging from maximally incongruent to maximally congruent in nine steps. Thirty participants reported where they perceived the odors, and how much they liked the solutions. Congruency had a positive linear effect both on odor referral to the oral cavity and on pleasantness. However, the effect of congruency on pleasantness was not mediated by odor referral. These results indicate that as an odor-taste mixture approximates a mental representation of a familiar food, its components are increasingly merged into one perceptual object sensed in the mouth. In parallel, the mixture is evaluated as increasingly pleasant, which promotes consumption of familiar foods that have been determined through experience to be non-toxic. While the modulatory role of congruency on pleasantness and odor referral was confirmed, our results also indicate that these effects arise through distinct perceptual mechanisms.

Mediation of the Association Between Vascular Risk Factors and Depressive Symptoms by C-Reactive Protein.

Background: This study examined whether C-reactive protein (CRP), a marker of low-grade systemic inflammation, mediates the association between vascular risk factor (VRF) burden and depressive symptoms. Methods: We drew on the prospective design of the UK Biobank to include participants with longitudinal data on VRF burden, CRP, and depressive symptoms. Total, direct, and indirect effects were estimated using regression-based mediation models while controlling for confounding by sociodemographic factors, baseline CRP, and baseline depression. Sensitivity analyses probed the robustness of results to unmeasured confounding. Results: We analyzed data from 10,470 participants from the UK Biobank (mean age = 56.75 years at baseline). Net of covariates, VRFs at baseline were associated with higher depressive symptoms at follow-up (total effect = 0.099; 95% CI, 0.002-0.163). CRP mediated this association (indirect effect = 0.010; 95% CI, 0.004-0.017), accounting for 10.0% (95% CI, 0.3%-30.0%) of the total effect of VRF burden on depressive symptoms. Exploratory analyses suggested that the total and indirect effects pertained to somatic depressive symptoms (tiredness and appetite). Conclusions: These results suggest that inflammation-promoting effects of VRFs may contribute to depressive symptoms in mid- and later life. However, the mediating pathway via CRP explains only a small part of the association between VRFs and depression after accounting for important covariates and may pertain to specific depressive symptoms. Future studies leveraging similar longitudinal designs are needed to further disentangle the time-varying effects between VRFs, inflammation, and certain depressive symptoms while addressing important confounders.

Associations between mental health, blood pressure and the development of hypertension.

Multiple studies have reported a link between mental health and high blood pressure with mixed or even contradictory findings. Here, we resolve those contradictions and further dissect the cross-sectional and longitudinal relationship between mental health, systolic blood pressure, and hypertension using extensive psychological, medical and neuroimaging data from the UK Biobank. We show that higher systolic blood pressure is associated with fewer depressive symptoms, greater well-being, and lower emotion-related brain activity. Interestingly, impending hypertension is associated with poorer mental health years before HTN is diagnosed. In addition, a stronger baseline association between systolic blood pressure and better mental health was observed in individuals who develop hypertension until follow-up. Overall, our findings offer insights on the complex relationship between mental health, blood pressure, and hypertension, suggesting that-via baroreceptor mechanisms and reinforcement learning-the association of higher blood pressure with better mental health may ultimately contribute to the development of hypertension.

Long-term Changes in Depressive Symptoms Before and After Stroke.

OBJECTIVES: To determine the trajectory of depressive symptoms several years before and after incident stroke. METHOD: We analysed data from 10,797 participants from the English Longitudinal Study of Ageing (ELSA) without a history of stroke at baseline (wave 1). We matched participants with incident stroke during the 12-year follow-up (waves 2-7) to stroke-free individuals using propensity scores accounting for age, gender, education, ethnicity, and vascular risk factors. Trajectories of depressive symptoms before and after stroke were analysed using multilevel models. RESULTS: Among the 10,797 participants (mean age 64.6 ± 9.9 years, 54.8 % women), we identified 425 individuals with incident stroke. At the assessment before stroke, these individuals demonstrated an increase in depressive symptoms compared to matched controls. There was a further increase in depressive symptoms in stroke survivors after the acute event, which persisted for several years. Symptom-level analyses revealed that differences in depressive symptoms between stroke survivors and stroke-free controls before and after stroke were most pronounced for mood- and fatigue-related symptoms. DISCUSSION: Incident stroke is associated with long-term increases in depressive symptoms. A small part of this increase occurs in the years before stroke, perhaps indicating the incipient pathological process. Particular attention should be paid to depressive symptoms in the long-term care of patients, and especially to fatigue-related symptoms.

The Age-Dependent Association Between Vascular Risk Factors and Depressed Mood.

OBJECTIVES: Cumulative burden of vascular risk factors (VRFs) has been linked to an increased risk of depressed mood. However, the role of age in this association is still unclear. Here, we investigated whether VRF burden is associated with levels and changes in depressed mood and whether these associations become stronger or weaker from mid- to later life. METHOD: We used longitudinal data from 5,689 participants (52-89 years) of the English Longitudinal Study of Ageing. A composite score incorporated the presence of 5 VRFs: hypertension, diabetes, smoking, obesity, and hypercholesterolemia. Second-order latent growth models were used to test whether levels and changes of depressed mood differed as a function of baseline VRF burden, and whether these associations were moderated by age. RESULTS: Baseline VRF burden showed a small association with higher levels of depressed mood (estimate = 0.081; 95% CI: 0.024, 0.138, p = .005). This association varied with age, such that it was stronger in midlife compared to later life (estimate = -0.007; 95% CI: -0.013, -0.002, p = .017). There was no evidence that VRF burden was associated with changes in depressed mood. DISCUSSION: Our findings suggest that VRF burden in midlife, but less so in later life, predicts individual differences in depressed mood. These findings are consistent with reports on the importance of midlife VRFs and support the idea that promotion of vascular health in this age group or earlier in life may be critical to maintain mental health across adulthood.

A limit of the subjective age bias: Feeling younger to a certain degree, but no more, is beneficial for life satisfaction.

The majority of adults feel considerably younger than their chronological age. Numerous studies suggest that maintaining a younger subjective age is linked to greater life satisfaction. However, whether there is a limit beyond which feeling younger becomes detrimental is not well understood. Here, we use response surface analysis to examine the relationships between subjective age, chronological age, and life satisfaction in in a large sample spanning adulthood (N = 7,356; 36-89 years). We find that there is a limit to feeling younger: People who feel younger by a certain amount, but not more, have the highest levels of life satisfaction. In addition, our findings suggest that the discrepancy between subjective and chronological age at which life satisfaction is highest increases across the adult age span. Taken together, these findings reveal that beyond a certain point, feeling younger than one's chronological age may be psychologically harmful. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Modulation of premotor cortex response to sequence motor learning during escitalopram intake.

The contribution of selective serotonin reuptake inhibitors to motor learning by inducing motor cortical plasticity remains controversial given diverse findings from positive preclinical data to negative findings in recent clinical trials. To empirically address this translational disparity, we use functional magnetic resonance imaging in a double-blind, randomized controlled study to assess whether 20 mg escitalopram improves sequence-specific motor performance and modulates cortical motor response in 64 healthy female participants. We found decreased left premotor cortex responses during sequence-specific learning performance comparing single dose and steady escitalopram state. Escitalopram plasma levels negatively correlated with the premotor cortex response. We did not find evidence in support of improved motor performance after a week of escitalopram intake. These findings do not support the conclusion that one week escitalopram intake increases motor performance but could reflect early adaptive plasticity with improved neural processing underlying similar task performance when steady peripheral escitalopram levels are reached.

Does depression after stroke negatively influence physical disability? A systematic review and meta-analysis of longitudinal studies.

BACKGROUND: Depression after stroke is common and has been proposed to negatively affect disability by preventing optimal physical rehabilitation and recovery. However, the nature of this influence remains poorly understood. Here, we synthesise longitudinal studies to examine the hypotheses that depression after stroke (i) hampers physical rehabilitation, (ii) prevents functional improvement during recovery, and (iii) is associated with poor functional outcomes. METHODS: A systematic literature search was conducted using the databases PubMed and Web of Science. A total of 5672 studies were screened; 28 met criteria for inclusion. The quality of included studies was assessed using the Newcastle-Ottawa Scale. RESULTS: Individual studies showed no consistent effects of depression post-stroke on (i) the effectiveness of physical rehabilitation and (ii) functional improvements during recovery. In contrast, random-effects models revealed that (iii) depression after stroke was associated with an increased risk for poor long-term disability (OR: 2.16, 95% CI 1.70-2.77). Overall, the quality of studies was moderate and there was evidence for publication bias. LIMITATIONS: The number of included studies was small. There was considerable methodological heterogeneity between studies, prohibiting meta-analyses for all effects of interest. Few studies examined the influence of antidepressants. CONCLUSIONS: Depressed stroke patients are generally more disabled. However, depressed mood might not restrict improvements in physical disability during rehabilitation and recovery, although it seems to be linked to a delayed increase in the risk of poor functional outcome. High-quality evidence from longitudinal studies is needed to clarify the precise mechanisms and temporal dynamics underlying these associations.

A mind-brain-body dataset of MRI, EEG, cognition, emotion, and peripheral physiology in young and old adults.

We present a publicly available dataset of 227 healthy participants comprising a young (N=153, 25.1±3.1 years, range 20-35 years, 45 female) and an elderly group (N=74, 67.6±4.7 years, range 59-77 years, 37 female) acquired cross-sectionally in Leipzig, Germany, between 2013 and 2015 to study mind-body-emotion interactions. During a two-day assessment, participants completed MRI at 3 Tesla (resting-state fMRI, quantitative T1 (MP2RAGE), T2-weighted, FLAIR, SWI/QSM, DWI) and a 62-channel EEG experiment at rest. During task-free resting-state fMRI, cardiovascular measures (blood pressure, heart rate, pulse, respiration) were continuously acquired. Anthropometrics, blood samples, and urine drug tests were obtained. Psychiatric symptoms were identified with Standardized Clinical Interview for DSM IV (SCID-I), Hamilton Depression Scale, and Borderline Symptoms List. Psychological assessment comprised 6 cognitive tests as well as 21 questionnaires related to emotional behavior, personality traits and tendencies, eating behavior, and addictive behavior. We provide information on study design, methods, and details of the data. This dataset is part of the larger MPI Leipzig Mind-Brain-Body database.

Captured by the pain: pain steady-state evoked potentials are not modulated by selective spatial attention.

Attention has been shown to affect the neural processing of pain. However, the exact mechanisms underlying this modulation remain unknown. Here, we used a new method called pain steady-state evoked potentials (PSSEPs) to investigate whether selective spatial attention affects EEG responses to tonic painful stimuli. In general, steady-state evoked potentials reflect changes in the EEG spectrum at a certain frequency that correspond to the frequency of a train of applied stimuli. In this study, high intensity transcutaneous electrical stimulation was delivered to both hands simultaneously with 31 Hz and 37 Hz, respectively. Subject׳s attention was directed to one of the two trains of stimulation in order to detect a small gap that was occasionally interspersed into the stimulus trains. Thereby, they had to ignore the stimulation applied to the other hand. Results show that PSSEPs were induced at 31 Hz and 37 Hz at frontal and central electrodes. PSSEPs occurred contralaterally to the respective hand stimulated with that frequency. Surprisingly, the magnitude of PSSEPs was not modulated by spatial attention towards one of the two stimuli. Our results indicate that attention can hardly be shifted between two simultaneously applied tonic painful stimulations.