Assessment of Bidirectional Relationships Between Physical Activity and Depression Among Adults: A 2-Sample Mendelian Randomization Study

Causal relationship between blood metabolites and risk of five infections: a Mendelian randomization study

OBJECTIVE

Infectious diseases continue to pose a significant threat in the field of global public health, and our understanding of their metabolic pathogenesis remains limited. However, the advent of genome-wide association studies (GWAS) offers an unprecedented opportunity to unravel the relationship between metabolites and infections.

METHODS

Univariable and multivariable Mendelian randomization (MR) was commandeered to elucidate the causal relationship between blood metabolism and five high-frequency infection phenotypes: sepsis, pneumonia, upper respiratory tract infections (URTI), urinary tract infections (UTI), and skin and subcutaneous tissue infection (SSTI). GWAS data for infections were derived from UK Biobank and the FinnGen consortium. The primary analysis was conducted using the inverse variance weighted method on the UK Biobank data, along with a series of sensitivity analyses. Subsequently, replication and meta-analysis were performed on the FinnGen consortium data.

RESULTS

After primary analysis and a series of sensitivity analyses, 17 metabolites were identified from UK Biobank that have a causal relationship with five infections. Upon joint analysis with the FinGen cohort, 7 of these metabolites demonstrated consistent associations. Subsequently, we conducted a multivariable Mendelian randomization analysis to confirm the independent effects of these metabolites. Among known metabolites, genetically predicted 1-stearoylglycerol (1-SG) (odds ratio [OR] = 0.561, 95% confidence interval [CI]: 0.403-0.780, P < 0.001) and 3-carboxy-4-methyl-5-propyl-2-furanpropanoate (CMPF) (OR = 0.780, 95%CI: 0.689-0.883, P < 0.001) was causatively associated with a lower risk of sepsis, and genetically predicted phenylacetate (PA) (OR = 1.426, 95%CI: 1.152-1.765, P = 0.001) and cysteine (OR = 1.522, 95%CI: 1.170-1.980, P = 0.002) were associated with an increased risk of UTI. Ursodeoxycholate (UDCA) (OR = 0.906, 95%CI: 0.829-0.990, P = 0.029) is a protective factor against pneumonia. Two unknown metabolites, X-12407 (OR = 1.294, 95%CI: 1.131-1.481, P < 0.001), and X-12847 (OR = 1.344, 95%CI: 1.152-1.568, P < 0.001), were also identified as independent risk factors for sepsis.

CONCLUSIONS

In this MR study, we demonstrated a causal relationship between blood metabolites and the risk of developing sepsis, pneumonia, and UTI. However, there was no evidence of a causal connection between blood metabolites and the risk of URTI or SSTI, indicating a need for larger-scale studies to further investigate susceptibility to certain infection phenotypes.

Causal associations between sleep traits and brain structure: a bidirectional Mendelian randomization study

BACKGROUND

Emerging evidence suggests bidirectional causal relationships between sleep disturbance and psychiatric disorders, but the underlying mechanisms remain unclear. Understanding the bidirectional causality between sleep traits and brain imaging-derived phenotypes (IDPs) will help elucidate the mechanisms. Although previous studies have identified a range of structural differences in the brains of individuals with sleep disorders, it is still uncertain whether grey matter (GM) volume alterations precede or rather follow from the development of sleep disorders.

RESULTS

After Bonferroni correction, the forward MR analysis showed that insomnia complaint remained positively associated with the surface area (SA) of medial orbitofrontal cortex (β, 0.26; 95% CI, 0.15-0.37; P = 5.27 × 10-6). In the inverse MR analysis, higher global cortical SA predisposed individuals less prone to suffering insomnia complaint (OR, 0.89; 95%CI, 0.85-0.94; P = 1.51 × 10-5) and short sleep (≤ 6 h; OR, 0.98; 95%CI, 0.97-0.99; P = 1.51 × 10-5), while higher SA in posterior cingulate cortex resulted in a vulnerability to shorter sleep durations (β, - 0.09; 95%CI, - 0.13 to - 0.05; P = 1.21 × 10-5).

CONCLUSIONS

Sleep habits not only result from but also contribute to alterations in brain structure, which may shed light on the possible mechanisms linking sleep behaviours with neuropsychiatric disorders, and offer new strategies for prevention and intervention in psychiatric disorders and sleep disturbance.

Assessment of the bidirectional causal association between frailty and depression: A Mendelian randomization study

BACKGROUND

Observational studies have demonstrated a strong bidirectional association between frailty and depression, but it remains unclear whether this association reflects causality. This study aimed to examine the bidirectional causal relationship between frailty and depression.

METHODS

Using genome-wide association study summary data, two-sample Mendelian randomization was performed to test for the potential bidirectional causality between frailty, as defined by both the frailty index and the frailty phenotype, and depression. Several frailty-related traits were additionally investigated, including weaker hand grip strength, slower walking pace and physical inactivity. Findings were replicated using an independent depression data source and verified using multiple sensitivity analyses.

RESULTS

Genetically predicted higher frailty index (odds ratio [OR], 1.86; P < 0.001), higher frailty phenotype score (OR, 2.79; P < 0.001), lower grip strength (OR, 1.23; P = 0.003), slower walking pace (OR, 1.55; P = 0.027) and physical inactivity (OR, 1.44; P = 0.003) all were associated with a higher risk of depression. As for the reverse direction, genetic liability to depression showed consistent associations with a higher frailty index (beta, 0.167; P < 0.001) and a higher frailty phenotype score (beta, 0.067; P = 0.001), but not with other frailty-related traits that were investigated. The results were stable across sensitivity analyses and across depression datasets.

CONCLUSIONS

Our findings add novel evidence supporting the bidirectional causal association between frailty and depression. Improving balance and muscle strength and increasing physical activity may be beneficial in both depression and frailty.

Systematic comparison of Mendelian randomisation studies and randomised controlled trials using electronic databases

OBJECTIVE

To scope the potential for (semi)-automated triangulation of Mendelian randomisation (MR) and randomised controlled trials (RCTs) evidence since the two methods have distinct assumptions that make comparisons between their results invaluable.

METHODS

We mined ClinicalTrials.Gov, PubMed and EpigraphDB databases and carried out a series of 26 manual literature comparisons among 54 MR and 77 RCT publications.

RESULTS

We found that only 13% of completed RCTs identified in ClinicalTrials.Gov submitted their results to the database. Similarly low coverage was revealed for Semantic Medline (SemMedDB) semantic triples derived from MR and RCT publications -36% and 12%, respectively. Among intervention types that can be mimicked by MR, only trials of pharmaceutical interventions could be automatically matched to MR results due to insufficient annotation with Medical Subject Headings ontology. A manual survey of the literature highlighted the potential for triangulation across a number of exposure/outcome pairs if these challenges can be addressed.

CONCLUSIONS

We conclude that careful triangulation of MR with RCT evidence should involve consideration of similarity of phenotypes across study designs, intervention intensity and duration, study population demography and health status, comparator group, intervention goal and quality of evidence.

Association between frailty and depression: A bidirectional Mendelian randomization study

Frailty and depression were linked in observational studies, but the causality remains ambiguous. We intended to explore it using Mendelian randomization (MR). We obtained frailty genome-wide association study (GWAS) data from UK Biobank and TwinGen meta-analysis, and depression GWAS data from Psychiatric Genomics Consortium (PGC) and FinnGen (respectively recorded as PD and FD). We performed univariable and multivariable-adjusted MR with adjustments for body mass index (BMI) and physical activity (PA). Frailty was significantly associated with elevated risks of PD (OR, 1.860; 95% CI, 1.439 to 2.405; P < 0.001) and FD (OR, 1.745; 95% CI, 1.193 to 2.552; P = 0.004), and depression was meanwhile a susceptible factor for frailty (PD: β, 0.146; 95% CI, 0.086 to 0.201; P < 0.001; and FD: β, 0.112; 95% CI, 0.051 to 0.174; P < 0.001). This association was robust after adjustments for BMI or PA. Our study provides evidence of the bidirectional causal association between frailty and depression from genetic perspectives.

Causal effect of body mass index and physical activity on the risk of joint sports injuries: Mendelian randomization analysis in the European population

BACKGROUND

Observational studies can suggest potential associations between variables but cannot establish a causal effect on their own. This study explored the causal associations between body mass index (BMI), physical activity (PA), and joint sports injuries.

METHODS

We conducted two-sample Mendelian randomization (MR) using publicly accessed genome-wide association studies (GWAS) datasets to investigate the causal effects of BMI and PA on joint sports injury risk. The inverse-variance weighted method was believed to be the primary MR analysis. Subsequently, sensitivity, pleiotropy, and heterogeneity analyses were employed to estimate the reliability of the results of the current research.

RESULTS

Genetically predicted increased BMI was causally related to the higher sports injury risk of the ankle-foot (OR 1.23, 95% CI 1.09-1.37, p = 4.20E-04), knee (OR 1.32, 95% CI 1.21-1.43, p = 1.57E-11), and shoulder (OR 1.23, 95% CI 1.08-1.40, p = 1.28E-03). Further, the mentioned effects were validated using another set of GWAS data on BMI. Similar causal linkages were exhibited between increased BMI and the growing risk of sports injuries of the ankle-foot (OR 1.34, 95% CI 1.13-1.60, p = 9.51E-04), knee (OR 1.26, 95% CI 1.09-1.45, p = 1.63E-03), and shoulder (OR 1.35, 95% CI 1.09-1.67, p = 5.66E-03). Additionally, accelerometer-based PA measurement (overall average acceleration) (AccAve) was negatively related to sports injuries of the ankle-foot (OR 0.93, 95% CI 0.87-0.99, p = 0.046) and lumbar spine (OR 0.68, 95% CI 0.51-0.92, p = 0.012). Furthermore, we verified that the effect of AccAve on the risk of injury at the ankle-foot still had statistical significance after adjusting BMI. Results were verified as reliable under all sensitive analyses.

CONCLUSIONS

This research determined that a higher BMI could raise the sports injury risk of the ankle-foot, knee, and shoulder, while an overall average acceleration PA could reduce the injury risk of the ankle-foot and lumbar spine. These conclusions contribute to a greater knowledge of the roles of BMI and PA in the mechanism of joint sports injuries and offer several suggestions for patients and clinicians.

Fatigue and Physical Activity in People after COVID-19 in Poland

OBJECTIVES

The purpose of this research was to look at the amount of fatigue and physical activity (PA) in individuals after COVID-19 in Poland and the correlation between fatigue and PA.

METHODS

The online research was carried out among adult Polish residents (122 women and 82 men) who had tested positive for SARS-CoV-2 during the previous year. The level of fatigue was measured using the Modified Fatigue Impact Scale (MFIS). The PA level was assessed using the International Physical Activity Questionnaire (IPAQ).

RESULTS

A total of 46.6% of the subjects had been ill with COVID-19 for more than 6 months before the time of the survey response. The MFIS total measure is 77 of the maximum score, and the median is 17. A total of 26% of respondents reported low activity, while 41% of respondents reported high activity. A statistically significant negative relationship was found between PA level and total fatigue score. The best scores for fatigue and PA were obtained by the subjects with mild COVID-19. The time since diagnosis (as opposed to older age and female sex) was not clearly associated with most measures.

CONCLUSIONS

PA may play an important role in regulating the severity of fatigue; it should be increased, especially in patients after COVID. Further studies are also needed to investigate the mechanism of differences in fatigue and PA.

Machine-learning-based head impact subtyping based on the spectral densities of the measurable head kinematics

BACKGROUND

Traumatic brain injury can be caused by head impacts, but many brain injury risk estimation models are not equally accurate across the variety of impacts that patients may undergo, and the characteristics of different types of impacts are not well studied. We investigated the spectral characteristics of different head impact types with kinematics classification.

METHODS

Data were analyzed from 3262 head impacts from lab reconstruction, American football, mixed martial arts, and publicly available car crash data. A random forest classifier with spectral densities of linear acceleration and angular velocity was built to classify head impact types (e.g., football, car crash, mixed martial arts). To test the classifier robustness, another 271 lab-reconstructed impacts were obtained from 5 other instrumented mouthguards. Finally, with the classifier, type-specific, nearest-neighbor regression models were built for brain strain.

RESULTS

The classifier reached a median accuracy of 96% over 1000 random partitions of training and test sets. The most important features in the classification included both low- and high-frequency features, both linear acceleration features and angular velocity features. Different head impact types had different distributions of spectral densities in low- and high-frequency ranges (e.g., the spectral densities of mixed martial arts impacts were higher in the high-frequency range than in the low-frequency range). The type-specific regression showed a generally higher R2 value than baseline models without classification.

CONCLUSION

The machine-learning-based classifier enables a better understanding of the impact kinematics spectral density in different sports, and it can be applied to evaluate the quality of impact-simulation systems and on-field data augmentation.

Weekend warrior physical activity pattern is associated with lower depression risk: Findings from NHANES 2007-2018

OBJECTIVE

This study aimed to explore the association between weekend warrior physical activity (PA) pattern and depression risk in American adults.

METHODS

Data of adults (n = 21,125) from NHANES 2007-2018 were used. Adults were categorized into 4 PA patterns (inactive, insufficiently active, weekend warrior, and regularly active) by self-reported PA levels. Participant characteristics in different groups were tested using the Rao & Scott adjusted χ2 test. Multivariate logistic regression models with adjustment for demographics data, behavioral factors and health condition were used to explore the association between PA patterns and depression risk. Finally, interaction analyses were conducted to test if the associations differ by gender, age, race, education level, income level and marital status.

RESULTS

Multivariate logistic regression models showed that insufficiently active, weekend warrior and regularly active adults had 31% (OR: 0.69, 95%CI:0.54-0.88), 57% (OR: 0.43, 95%CI:0.25-0.74) and 54% (OR: 0.46, 95%CI:0.39-0.54) reduced depression risk when compared with inactive adults, respectively. When compared with regularly active adults, inactive (OR: 2.188, 95%CI:1.842-2.600) and insufficiently active (OR: 1.505, 95%CI:1.159-1.955) adults had elevated depression risk, but no significant difference was found between weekend warrior (OR: 0.949, 95%CI:0.538-1.675) and regularly active adults. Moreover, the associations did not differ by demographic variables.

CONCLUSIONS

This study showed that adults who engaged in either regularly active pattern or weekend warrior pattern, experienced lower risk of depression compared to inactive adults. Weekend warrior and regularly active patterns showed similar benefits for lowering depression risk in adults, encouraging adults to take up PA in limited sessions.

Illuminating the potential causality of serum level of matrix metalloproteinases and the occurrence of cardiovascular and cerebrovascular diseases: a Mendelian randomization study

BACKGROUND

It is still not clear that whether the expression levels of matrix metalloproteinases (MMPs) family are associated with cardiovascular and cerebrovascular diseases (CCDs) in genetic level. We explored the causal role of 12 members of MMPs in CCDs with mendelian randomization (MR) method to facilitate further exploring the underlying mechanisms.

METHODS

The relationship between MMPs and CCDs including intracerebral hemorrhage (ICH), hypertension, coronary heart disease (CHD), atrial fibrillation (AF), and outstanding risk factors of type II diabetes were determined with the inverse variance-weighted (IVW) method. The sensitivity analyses including MR-Egger regression, weighted median estimation, and MR pleiotropy residual sum and outlier were utilized to test the robustness of the results generated from the MR method.

RESULTS

We found that a higher serum level of MMP-12 was related to a lower risk of ICH (OR = 0.8287, 95% CI: 0.7526-0.9125, p = 0.00013), but not hypertension, CHD, type II diabetes or AF. And our study also revealed that a higher serum level of MMP-8 could result in a lower risk of hypertension (OR = 0.9976, 95% CI: 0.9964-0.9988, p = 0.00012) and AF (OR = 0.9851, 95% CI: 0.9741-0.9963, p = 0.0092), but not ICH, CHD or type II diabetes. All other members of MMPs other than MMP-8 and MMP-12 showed no statistical association with CCDs according to this study. Sensitivity analyses confirmed the reliability of our results.

CONCLUSIONS

We provided statistical evidences for a potential causal relationship between MMP-12 and ICH, as well as MMP-8 and hypertension, while other MMPs showed weaker association with CCDs. The underlying mechanisms need to be established in the future.

Physical Activity in Women with Endometriosis: Less or More Compared with a Healthy Control?

BACKGROUND

Endometriosis, i.e., endometrial-like tissue outside the uterus, is a chronic inflammatory condition affecting physical functioning. However, the specific levels of physical activity (PA) in the context of endometriosis and different disease symptoms remain unclear.

METHODS

This multi-center, cross-sectional study compared PA levels and influencing factors in endometriosis patients and non-endometriosis patients. Data were collected through questionnaires. Endometriosis was surgically confirmed. A statistical analysis was performed with appropriate tests.

RESULTS

The study included 460 women with endometriosis and 460 age-matched women without this condition. The two groups did not differ significantly in terms of age, education level, or stable partnership. Women with endometriosis exhibited lower PA levels, practicing fewer hours of sports weekly and climbing fewer stairs daily compared to the control group. These differences remained significant after controlling for confounding factors. Factors such as endometriosis, current dysmenorrhea, and depression were associated with decreased PA.

CONCLUSIONS

These findings suggest that women with endometriosis engage in less PA compared to those without this condition. These results highlight the need for interventions to promote increased PA in endometriosis patients and harness the associated health benefits. Further research is warranted to explore the underlying mechanisms and develop tailored exercise therapies for this population.

The Physiological and Molecular Links Between Physical Activity and Brain Health: A Review

There is currently an epidemic of sedentary behavior throughout the world, leading to negative impacts on physical health and contributing to both mortality and burden of disease. The consequences of this also impact the brain, where increased levels of cognitive decline are observed in individuals who are more sedentary. This review explores the physiological and molecular responses to our sedentary propensity, its contribution to several medical conditions and cognitive deficits, and the benefits of moderate levels of physical activity and exercise. Also presented is the recommended level of activity for overall physical health improvement.

Challenges in Using mHealth Data From Smartphones and Wearable Devices to Predict Depression Symptom Severity: Retrospective Analysis

BACKGROUND

Major depressive disorder (MDD) affects millions of people worldwide, but timely treatment is not often received owing in part to inaccurate subjective recall and variability in the symptom course. Objective and frequent MDD monitoring can improve subjective recall and help to guide treatment selection. Attempts have been made, with varying degrees of success, to explore the relationship between the measures of depression and passive digital phenotypes (features) extracted from smartphones and wearables devices to remotely and continuously monitor changes in symptomatology. However, a number of challenges exist for the analysis of these data. These include maintaining participant engagement over extended time periods and therefore understanding what constitutes an acceptable threshold of missing data; distinguishing between the cross-sectional and longitudinal relationships for different features to determine their utility in tracking within-individual longitudinal variation or screening individuals at high risk; and understanding the heterogeneity with which depression manifests itself in behavioral patterns quantified by the passive features.

OBJECTIVE

We aimed to address these 3 challenges to inform future work in stratified analyses.

METHODS

Using smartphone and wearable data collected from 479 participants with MDD, we extracted 21 features capturing mobility, sleep, and smartphone use. We investigated the impact of the number of days of available data on feature quality using the intraclass correlation coefficient and Bland-Altman analysis. We then examined the nature of the correlation between the 8-item Patient Health Questionnaire (PHQ-8) depression scale (measured every 14 days) and the features using the individual-mean correlation, repeated measures correlation, and linear mixed effects model. Furthermore, we stratified the participants based on their behavioral difference, quantified by the features, between periods of high (depression) and low (no depression) PHQ-8 scores using the Gaussian mixture model.

RESULTS

We demonstrated that at least 8 (range 2-12) days were needed for reliable calculation of most of the features in the 14-day time window. We observed that features such as sleep onset time correlated better with PHQ-8 scores cross-sectionally than longitudinally, whereas features such as wakefulness after sleep onset correlated well with PHQ-8 longitudinally but worse cross-sectionally. Finally, we found that participants could be separated into 3 distinct clusters according to their behavioral difference between periods of depression and periods of no depression.

CONCLUSIONS

This work contributes to our understanding of how these mobile health-derived features are associated with depression symptom severity to inform future work in stratified analyses.

Modifiable risk factors of major depressive disorder: A Mendelian randomization study

Identifying modifiable risk factors early on is essential to prevent major depressive disorder (MDD). This study systematically investigated the causal relationship between 19 modifiable risk factors and MDD. Single-nucleotide polymorphisms (SNPs) associated with 19 potentially modifiable risk factors were screened via the genome-wide association study (GWAS) enrolling individuals of European descent. Summary-level data for MDD (59,851 cases and 113,154 controls) were extracted from the UK Biobank. The inverse-variance-weighted (IVW) method was utilized as the primary analysis. Sensitivity analyses were performed using the MR-Egger method, the Maximum likelihood method, the MR-pleiotropy residual sum outlier (MR-PRESSO) method, and MR-robust adjusted profile score (MR-RAPS) method. MR-Egger regression, heterogeneity tests, pleiotropy tests, and leave-one-out tests were also performed to analyze sensitivity. The MR Steiger test was used to verify the directionality of the exposure to the outcome. Genetically predicted smoking initiation increased the risk of MDD (P = 6.00E-09), while smoking status: never and past tobacco smoking decreased the risk of MDD (all P < 0.01). In addition, education level was inversely associated with MDD risk (all P < 0.01). Genetically instrumented sleeplessness/insomnia, daytime naps, and nap during the day were positively related to the risk of MDD (all P < 0.01). Personal feelings, including guilt, hurt, tension, and worry too long after an embarrassing experience, had a suggestive increased risk for MDD (all P < 0.000). The remaining five modifiable risk factors were all causally associated with the risk of MDD, including neuroticism, neuroticism scores, body mass index (BMI), average total household income before tax, and types of physical activity in the last 4 weeks (all P < 0.01). All 19 potentially modifiable risk factors were causally associated with the risk of MDD. The main hypothesis of this MR study was that identifying and intervening in these 19 potentially modifiable risk factors could be beneficial to the prevention and treatment of MDD and further reduce mortality and economic burden.

Evidence of causal effects of blood pressure on back pain and back pain on type II diabetes provided by a bidirectional Mendelian randomization study

BACKGROUND CONTEXT

Cardiovascular risk factors (hypertension, dyslipidemia, and type II diabetes) have been proposed as risk factors for back pain. However, few longitudinal studies have found significant associations between cardiovascular risk factors and back pain, and these may be explained by confounding or reverse causation.

PURPOSE

To examine potential causal effects of cardiovascular risk factors on back pain, and vice versa.

STUDY DESIGN

Bidirectional Mendelian randomization (MR) study.

PATIENT SAMPLES

Genome-wide association studies (GWAS) with sample sizes between 173,082 and 1,028,947 participants.

OUTCOME MEASURES

Outcomes included (1) back pain associated with health care use (BP-HC) in the forward MR; and (2) seven cardiovascular phenotypes in the reverse MR, including 2 measurements used for the evaluation of hypertension (diastolic blood pressure and systolic blood pressure), 4 phenotypes related to dyslipidemia (LDL cholesterol, HDL cholesterol, total cholesterol, and triglycerides), and type II diabetes.

METHODS

We used summary statistics from large, publicly available GWAS for BP-HC and the 7 cardiovascular phenotypes to obtain genetic instrumental variables. We examined MR evidence for causal associations using inverse-variance weighted (IVW) analysis, Causal Analysis Using Summary Effect (CAUSE), and sensitivity analyses.

RESULTS

In forward MR analyses of seven cardiovascular phenotypes, diastolic blood pressure was associated with BP-HC across all analyses (IVW estimate: OR = 1.10 per 10.5 mm Hg increase [1.04-1.17], p-value = .001), and significant associations of systolic blood pressure with BP-HC were also found (IVW estimate: OR = 1.09 per 19.3 mm Hg increase [1.04-1.15], p-value = .0006). In reverse MR analyses, only type II diabetes was associated with BP-HC across all analyses (IVW estimate: OR = 1.40 [1.13-1.73], p-value = .002).

CONCLUSIONS

These findings from analyses of large, population-based samples indicate that higher blood pressure increases the risk of BP-HC, and BP-HC itself increases the risk of type II diabetes.

Testing the causal relationships of physical activity and sedentary behaviour with mental health and substance use disorders: a Mendelian randomisation study

Observational studies suggest that physical activity can reduce the risk of mental health and substance use disorders. However, it is unclear whether this relationship is causal or explained by confounding bias (e.g., common underlying causes or reverse causality). We investigated the bidirectional causal relationship of physical activity (PA) and sedentary behaviour (SB) with ten mental health and substance use disorders, applying two-sample Mendelian Randomisation (MR). Genetic instruments for the exposures and outcomes were derived from the largest available, non-overlapping genome-wide association studies (GWAS). Summary-level data for objectively assessed PA (accelerometer-based average activity, moderate activity, and walking) and SB and self-reported moderate-to-vigorous PA were obtained from the UK Biobank. Data for mental health/substance use disorders were obtained from the Psychiatric Genomics Consortium and the GWAS and Sequencing Consortium of Alcohol and Nicotine Use. MR estimates were combined using inverse variance weighted meta-analysis (IVW). Sensitivity analyses were conducted to assess the robustness of the results. Accelerometer-based average PA was associated with a lower risk of depression (b = -0.043, 95% CI: -0.071 to -0.016, effect size[OR] = 0.957) and cigarette smoking (b = -0.026; 95% CI: -0.035 to -0.017, effect size[β] = -0.022). Accelerometer-based SB decreased the risk of anorexia (b = -0.341, 95% CI: -0.530 to -0.152, effect size[OR] = 0.711) and schizophrenia (b = -0.230; 95% CI: -0.285 to -0.175, effect size[OR] = 0.795). However, we found evidence of reverse causality in the relationship between SB and schizophrenia. Further, PTSD, bipolar disorder, anorexia, and ADHD were all associated with increased PA. This study provides evidence consistent with a causal protective effect of objectively assessed but not self-reported PA on reduced depression and cigarette smoking. Objectively assessed SB had a protective relationship with anorexia. Enhancing PA may be an effective intervention strategy to reduce depressive symptoms and addictive behaviours, while promoting sedentary or light physical activities may help to reduce the risk of anorexia in at-risk individuals.

A two-sample mendelian randomization analysis investigates associations between gut microbiota and infertility

Observational studies have provided evidence of a correlation between alterations in gut microbiota composition and infertility. However, concrete proof supporting the causal relationship is still lacking. We performed a Mendelian randomization study to assess whether genetically gut microbiota composition influences the risk of infertility. The genetic data pertaining to gut microbiota were obtained from a genome-wide association study meta-analysis, which was conducted among 24 cohorts (18,340 participants) from the international MiBioGen consortium. By the primary method of assessing causality, we have identified 2 family taxa, 2 genus taxa, and 1 order taxa that were linked to a low risk of male infertility, while 1 genus taxa were associated with a high risk of male infertility. Furthermore, we have discovered 6 genus taxa, 1 phylum taxa, 1 class taxa, 1 order taxa, and 1 family taxa that were associated with a low risk of female infertility, while 1 genus taxa were linked to a high risk of female infertility. This study successfully confirmed that there was a causal link between gut microbiota and infertility. The identification of these specific strains through genetic prediction offers a valuable insight for early diagnosis, prevention, and treatment of infertility.

Association between depression and COPD: results from the NHANES 2013-2018 and a bidirectional Mendelian randomization analysis

BACKGROUND

Observational studies showed a bidirectional association between depression and chronic obstructive pulmonary disease (COPD). However, it is unclear whether the observed association is causal. Thus we estimated the relationship using observational studies combined with bidirectional Mendelian randomization [MR].

MATERIALS AND METHODS

The study included 9977 participants from the 2013-2018 National Health and Nutrition Examination Survey and used weighted logistic regression analysis to assess the association between depression and COPD, followed by a bidirectional Mendelian randomization analysis to verify their causality.

RESULTS

Adjusted-weighted logistic regression in observational studies showed a significant association between COPD and mild depression (OR (95% CI): 1.81 (1.30, 2.52), P = 0.002) and COPD and depression (OR (95% CI): 1.93 (1.49, 2.50), P < 0.001). MR suggested depression may play a causal role in COPD risk (OR (95% CI): 1.45 (1.32, 1.60), P < 0.001), but more evidence for reverse causation is lacking (reverse MR OR (95% CI): 1.03 (0.99, 1.07), P = 0.151).

CONCLUSION

In conclusion, our study found depression may play a potential causal role in the morbidity of COPD suggesting depression might be the etiology of COPD. This finding needs to be validated in further prospective cohort studies with large sample sizes and adequate follow-up time.

Objectively assessed sleep and physical activity in depression subtypes and its mediating role in their association with cardiovascular risk factors

The aims of this study were to investigate the associations of major depressive disorder (MDD) and its subtypes (atypical, melancholic, combined, unspecified) with actigraphy-derived measures of sleep, physical activity and circadian rhythms; and test the potentially mediating role of sleep, physical activity and circadian rhythms in the well-established associations of the atypical MDD subtype with Body Mass Index (BMI) and the metabolic syndrome (MeS). The sample consisted of 2317 participants recruited from an urban area, who underwent comprehensive somatic and psychiatric evaluations. MDD and its subtypes were assessed via semi-structured diagnostic interviews. Sleep, physical activity and circadian rhythms were measured using actigraphy. MDD and its subtypes were associated with several actigraphy-derived variables, including later sleep midpoint, low physical activity, low inter-daily stability and larger intra-individual variability of sleep duration and relative amplitude. Sleep midpoint and physical activity fulfilled criteria for partial mediation of the association between atypical MDD and BMI, and physical activity also for partial mediation of the association between atypical MDD and MeS. Our findings confirm associations of MDD and its atypical subtype with sleep and physical activity, which are likely to partially mediate the associations of atypical MDD with BMI and MeS, although most of these associations are not explained by sleep and activity variables. This highlights the need to consider atypical MDD, sleep and sedentary behavior as cardiovascular risk factors.

Association between intake of the n-3 polyunsaturated fatty acid docosahexaenoic acid (n-3 PUFA DHA) and reduced risk of ovarian cancer: A systematic Mendelian Randomization study

BACKGROUND & AIMS

Whether the intake of docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, is beneficial for ovarian cancer (OC) remains controversial and we hope to disentangle this puzzle using genetic data from large-scale populations in European and Asian.

METHODS

We employed, for the first time, a systematic Mendelian randomization (MR) design to comprehensively evaluate the causal effect of plasma DHA levels, an objective biomarker of DHA intake, on OC risk in European and then verified the extrapolation of the results in the Asian. Data in the analysis included genetic association data obtained from large-scale genome-wide association studies with 13,499 individuals for plasma DHA measurements and 66,450 individuals for OC in the European population, and 1361 individuals for plasma DHA measurements and 61,457 individuals for OC in the Asian population. The causal relationship between DHA and OC was estimated using the inverse-variance weighted approach, together with extensive validation and sensitivity analyses to verify the main results.

RESULTS

In the European population, MR evidence suggested a causal relationship between higher plasma DHA levels and lower OC risk (OR, 0.89 for OC per one-SD increment in DHA; 95% CI, 0.83 to 0.96; P = 0.003). Subgroup analysis by histological type of OC indicated that this observed association was stronger among endometrioid ovarian cancer (EOC) (OR, 0.82; 95% CI, 0.69 to 0.96; P = 0.014). A similar causal association of borderline significance was reached in the Asian replication set. The above results were consistently supported by a series of validation and sensitivity analyses.

CONCLUSION

Our study provided robust genetic evidence for a protective association between plasma DHA levels and lower risk of OC, especially EOC, in the European population. These findings may inform prevention strategies and interventions directed towards DHA intake and OC.

Optimal Physical Activity Is Associated with the Reduction of Depressive Symptoms via Neuroticism and Resilience

BACKGROUND

Personality traits, such as neuroticism, that results in vulnerability to stress, and resilience, a measure of stress coping, are closely associated with the onset of depressive symptoms, whereas regular physical activity habits have been shown to reduce depressive symptoms. In this study, the mediating effects of neuroticism and resilience between physical activity duration and depressive symptoms were investigated by a covariance structure analysis.

METHODS

Between April 2017 and April 2018, 526 adult volunteers were surveyed using self-administered questionnaires. Demographic information, habitual physical activity duration (PAD), neuroticism, and resilience were investigated. The effects of these factors on depressive symptoms were analyzed by a covariance structure analysis. This study was conducted with the approval of the Medical Ethics Committee of Tokyo Medical University.

RESULTS

The dose-response curves of physical activity duration and depression scores were U-shaped: the optimal physical activity duration for the lowest depression score was 25.7 h/week. We found that the greater the difference from the optimal PAD, the higher the neuroticism and the lower the resilience, and the more severe the depressive symptoms. Covariance structure analysis demonstrated that neuroticism and resilience significantly and completely mediated the effects of the difference from the optimal PAD on depressive symptoms (coefficient of determination R² = 0.349).

CONCLUSION

Our study suggests that there is an optimal PAD that reduces depressive symptoms, and that a greater difference from the optimal PAD increases depressive symptoms through neuroticism and resilience.

Emotional abuse and depressive symptoms among the adolescents: the mediation effect of social anxiety and the moderation effect of physical activity

Background

Childhood maltreatment has been identified as a risk factor for depressive symptoms. Social anxiety is closely associated with depression. Physical activity has been regarded as an underlying protective factor. Little is known about the complex relations among these factors in Chinese middle school students. This study aimed to explore whether social anxiety mediated the association between childhood maltreatment and depressive symptoms and investigate whether physical activity moderated the indirect or direct effect of the mediation model.

Methods

A total of 1,570 middle school students were recruited and measured for childhood maltreatment (measured by Childhood Trauma Questionnaire-Short Form Chinese version), social anxiety (as the mediator, measured by the Chinese simplified version of Social Anxiety Scale for Adolescents), depressive symptoms (measured by the Chinese version of Depression Anxiety Stress Scales-21), physical activity (as the moderator), and covariates such as age, sex, and nationality. The proposed relationships were tested using mediation and moderated mediation models.

Results

Emotional abuse was directly associated with depression, and the association between emotional abuse and depression was partially mediated by social anxiety. The associations between emotional abuse with depression and with social anxiety were moderated by physical activity.

Conclusion

This study revealed the mediating role of social anxiety and the moderating role of physical activity between emotional abuse and depression, which emphasizes the potential benefits of sufficient physical activity to reduce social anxiety and depressive symptoms, and more intervention studies should be conducted to explore the direct influence of sufficient physical activity in the future.

Bridge connection between depression and anxiety symptoms and lifestyles in Chinese residents from a network perspective

Background

Lifestyle habits are vital components of the culture of mental health treatment settings. We examined the bridge connection between depressive and anxiety symptoms and lifestyles from a network perspective using a population-based study.

Methods

Face-to-face interviews were conducted with a provincially representative sample of 13,768 inhabitants from the Guangdong Sleep and Psychosomatic Health Survey based on standardized evaluation techniques. We identified the central symptoms by expected influence. The interconnection between depression and anxiety symptoms, as well as the bridge connectivity linking depression-anxiety symptoms and lifestyle factors, were assessed using the bridge centrality index. Network stability and sensibility analyses were performed using a case-dropping bootstrap procedure.

Results

The core symptom that exhibited the highest expected influence was fatigue or little energy, followed by uncontrollable worry, trouble relaxing, and sad mood in the depression-anxiety symptoms network, while guilt was the most interconnected symptom and had the highest bridge strength. Surrounding nodes of each node explained an average variance of 57.63%. Additionally, suicidal thoughts were recognized as collective bridging symptoms connecting lifestyle variables in the network integrating depression-anxiety symptoms with lifestyle factors. Current tobacco and alcohol consumption were positively associated with suicidal thoughts and irritability. Habitual diet rhythm and physical exercise frequency were linked to suicidal thoughts, guilt, and poor appetite or overeating. Suicidal thoughts, irritability, and guilt indicated the greatest connectivity with lifestyle factors. All networks had high stability and accuracy.

Conclusion

These highlighted core and bridge symptoms could serve as latent targets for the prevention and intervention of comorbid depression and anxiety. It might be crucial for clinical practitioners to design effective and targeted treatment and prevention strategies aiming at specific lifestyles and behaviors.

Running from stress: a perspective on the potential benefits of exercise-induced small extracellular vesicles for individuals with major depressive disorder

Aerobic exercise promotes beneficial effects in the brain including increased synaptic plasticity and neurogenesis and regulates neuroinflammation and stress response via the hypothalamic-pituitary-adrenal axis. Exercise can have therapeutic effects for numerous brain-related pathologies, including major depressive disorder (MDD). Beneficial effects of aerobic exercise are thought to be mediated through the release of "exerkines" including metabolites, proteins, nucleic acids, and hormones that communicate between the brain and periphery. While the specific mechanisms underlying the positive effects of aerobic exercise on MDD have not been fully elucidated, the evidence suggests that exercise may exert a direct or indirect influence on the brain via small extracellular vesicles which have been shown to transport signaling molecules including "exerkines" between cells and across the blood-brain barrier (BBB). sEVs are released by most cell types, found in numerous biofluids, and capable of crossing the BBB. sEVs have been associated with numerous brain-related functions including neuronal stress response, cell-cell communication, as well as those affected by exercise like synaptic plasticity and neurogenesis. In addition to known exerkines, they are loaded with other modulatory cargo such as microRNA (miRNA), an epigenetic regulator that regulates gene expression levels. How exercise-induced sEVs mediate exercise dependent improvements in MDD is unknown. Here, we perform a thorough survey of the current literature to elucidate the potential role of sEVs in the context of neurobiological changes seen with exercise and depression by summarizing studies on exercise and MDD, exercise and sEVs, and finally, sEVs as they relate to MDD. Moreover, we describe the links between peripheral sEV levels and their potential for infiltration into the brain. While literature suggests that aerobic exercise is protective against the development of mood disorders, there remains a scarcity of data on the therapeutic effects of exercise. Recent studies have shown that aerobic exercise does not appear to influence sEV size, but rather influence their concentration and cargo. These molecules have been independently implicated in numerous neuropsychiatric disorders. Taken together, these studies suggest that concentration of sEVs are increased post exercise, and they may contain specifically packaged protective cargo representing a novel therapeutic for MDD.

Dissecting the causal association between social or physical inactivity and depression: a bidirectional two-sample Mendelian Randomization study

A growing body of research suggests that social or physical activity can affect the risk of Major depressive disorder (MDD). However, the bidirectional relationship between them remains to be clarified further, especially between inactivity and MDD. Here, we performed a two-sample Mendelian Randomization analysis using genetic variants associated with social/physical activities and MDD, and assessed the mediating effect of obesity-related measures and brain imaging phenotypes. The dataset on MDD, social activities, and physical activities included 500,199; 461,369; 460,376 individuals, respectively. Information regarding body mass index (BMI), body fat percentage (BFP), IDPs for 454,633; 461,460; 8,428 participants, respectively. We identified bidirectional causal relationships between sport clubs or gyms, strenuous sports, heavy do-it-youself, other exercises and MDD. We also observed that leisure/social inactivity (odds ratio [OR] = 1.64; P = 5.14 × 10-5) or physical inactivity (OR = 3.67; P = 1.99 × 10-5) caused an increased risk of MDD, which were partially mediated by BMI or BFP and masked by the weighted-mean orientation dispersion index of left acoustic radiation or volume of right caudate. Furthermore, we discovered that MDD increased the risk of leisure/social inactivity (OR = 1.03; P = 9.89 × 10-4) or physical inactivity (OR = 1.01; P = 7.96 × 10-4). In conclusions, we found that social/physical activities reduced the risk of MDD, while MDD in turn hindered social/physical activities. Inactivity may increase the risk of MDD, which was mediated or masked by brain imaging phenotypes. These results help to understand the manifestations of MDD and provide evidence and direction for the advancement of intervention and prevention.

Improvements in Physical Function and Pain Interference and Changes in Mental Health Among Patients Seeking Musculoskeletal Care

Importance

Among patients seeking care for musculoskeletal conditions, there is mixed evidence regarding whether traditional, structure-based care is associated with improvement in patients' mental health.

Objective

To determine whether improvements in physical function and pain interference are associated with meaningful improvements in anxiety and depression symptoms among patients seeking musculoskeletal care.

Design, Setting, and Participants

This cohort study included adult patients treated by an orthopedic department of a tertiary care US academic medical center from June 22, 2015, to February 9, 2022. Eligible participants presented between 4 and 6 times during the study period for 1 or more musculoskeletal conditions and completed Patient-Reported Outcomes Measurement Information System (PROMIS) measures as standard care at each visit.

Exposure

PROMIS Physical Function and Pain Interference scores.

Main Outcomes and Measures

Linear mixed effects models were used to determine whether improvements in PROMIS Anxiety and PROMIS Depression scores were associated with improved PROMIS Physical Function or Pain Interference scores after controlling for age, gender, race, and PROMIS Depression (for the anxiety model) or PROMIS Anxiety (for the depression model). Clinically meaningful improvement was defined as 3.0 points or more for PROMIS Anxiety and 3.2 points or more for PROMIS Depression.

Results

Among 11 236 patients (mean [SD] age, 57 [16] years), 7218 (64.2%) were women; 120 (1.1%) were Asian, 1288 (11.5%) were Black, and 9706 (86.4%) were White. Improvements in physical function (β = -0.14; 95% CI, -0.15 to -0.13; P < .001) and pain interference (β = 0.26; 95% CI, 0.25 to 0.26; P < .001) were each associated with improved anxiety symptoms. To reach a clinically meaningful improvement in anxiety symptoms, an improvement of 21 PROMIS points or more (95% CI, 20-23 points) on Physical Function or 12 points or more (95% CI, 12-12 points) on Pain Interference would be required. Improvements in physical function (β = -0.05; 95% CI, -0.06 to -0.04; P < .001) and pain interference (β = 0.04; 95% CI, 0.04 to 0.05; P < .001) were not associated with meaningfully improved depression symptoms.

Conclusions and Relevance

In this cohort study, substantial improvements in physical function and pain interference were required for association with any clinically meaningful improvement in anxiety symptoms, and were not associated with any meaningful improvement in depression symptoms. Patients seeking musculoskeletal care clinicians providing treatment cannot assume that addressing physical health will result in improved symptoms of depression or potentially even sufficiently improved symptoms of anxiety.

Higher immune-related gene expression in major depression is independent of CRP levels: results from the BIODEP study

Compelling evidence demonstrates that some individuals suffering from major depressive disorder (MDD) exhibit increased levels of inflammation. Most studies focus on inflammation-related proteins, such as serum or plasma C-reactive protein (CRP). However, the immune-related modifications associated with MDD may be not entirely captured by CRP alone. Analysing mRNA gene expression levels, we aimed to identify broader molecular immune-related phenotypes of MDD. We examined 168 individuals from the non-interventional, case-control, BIODEP study, 128 with a diagnosis of MDD and 40 healthy controls. Individuals with MDD were further divided according to serum high-sensitivity (hs)CRP levels (n = 59 with CRP <1, n = 33 with CRP 1-3 and n = 36 with CRP >3 mg/L). We isolated RNA from whole blood and performed gene expression analyses using RT-qPCR. We measured the expression of 16 immune-related candidate genes: A2M, AQP4, CCL2, CXCL12, CRP, FKBP5, IL-1-beta, IL-6, ISG15, MIF, GR, P2RX7, SGK1, STAT1, TNF-alpha and USP18. Nine of the 16 candidate genes were differentially expressed in MDD cases vs. controls, with no differences between CRP-based groups. Only CRP mRNA was clearly associated with serum CRP. In contrast, plasma (proteins) IL-6, IL-7, IL-8, IL-10, IL-12/IL-23p40, IL-16, IL-17A, IFN-gamma and TNF-alpha, and neutrophils counts, were all differentially regulated between CRP-based groups (higher in CRP >3 vs. CRP <1 and/or controls), reflecting the gradient of CRP values. Secondary analyses on MDD individuals and controls with CRP values <1 mg/L (usually interpreted as 'no inflammation') confirmed MDD cases still had significantly different mRNA expression of immune-related genes compared with controls. These findings corroborate an immune-related molecular activation in MDD, which appears to be independent of serum CRP levels. Additional biological mechanisms may then be required to translate this mRNA signature into inflammation at protein and cellular levels. Understanding these mechanisms will help to uncover the true immune abnormalities in depression, opening new paths for diagnosis and treatment.

Clinical guidelines for the use of lifestyle-based mental health care in major depressive disorder: World Federation of Societies for Biological Psychiatry (WFSBP) and Australasian Society of Lifestyle Medicine (ASLM) taskforce

OBJECTIVES

The primary objectives of these international guidelines were to provide a global audience of clinicians with (a) a series of evidence-based recommendations for the provision of lifestyle-based mental health care in clinical practice for adults with Major Depressive Disorder (MDD) and (b) a series of implementation considerations that may be applicable across a range of settings.

METHODS

Recommendations and associated evidence-based gradings were based on a series of systematic literature searches of published research as well as the clinical expertise of taskforce members. The focus of the guidelines was eight lifestyle domains: physical activity and exercise, smoking cessation, work-directed interventions, mindfulness-based and stress management therapies, diet, sleep, loneliness and social support, and green space interaction. The following electronic bibliographic databases were searched for articles published prior to June 2020: PubMed, EMBASE, The Cochrane Library (Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Methodology Register), CINAHL, PsycINFO. Evidence grading was based on the level of evidence specific to MDD and risk of bias, in accordance with the World Federation of Societies for Biological Psychiatry criteria.

RESULTS

Nine recommendations were formed. The recommendations with the highest ratings to improve MDD were the use of physical activity and exercise, relaxation techniques, work-directed interventions, sleep, and mindfulness-based therapies (Grade 2). Interventions related to diet and green space were recommended, but with a lower strength of evidence (Grade 3). Recommendations regarding smoking cessation and loneliness and social support were based on expert opinion. Key implementation considerations included the need for input from allied health professionals and support networks to implement this type of approach, the importance of partnering such recommendations with behaviour change support, and the need to deliver interventions using a biopsychosocial-cultural framework.

CONCLUSIONS

Lifestyle-based interventions are recommended as a foundational component of mental health care in clinical practice for adults with Major Depressive Disorder, where other evidence-based therapies can be added or used in combination. The findings and recommendations of these guidelines support the need for further research to address existing gaps in efficacy and implementation research, especially for emerging lifestyle-based approaches (e.g. green space, loneliness and social support interventions) where data are limited. Further work is also needed to develop innovative approaches for delivery and models of care, and to support the training of health professionals regarding lifestyle-based mental health care.

Association between circulating fatty acid metabolites and asthma risk: a two-sample bidirectional Mendelian randomization study

BACKGROUND

Fatty acids are involved in a wide range of immunological responses in humans. Supplementation of polyunsaturated fatty acids has been reported to help alleviate symptoms and airway inflammation in asthma patients, whereas the effects of fatty acids on the actual risk of asthma remain controversial. This study comprehensively investigated the causal effects of serum fatty acids on asthma risk using two-sample bidirectional Mendelian Randomization (MR) analysis.

METHODS

Genetic variants strongly associated with 123 circulating fatty acid metabolites were extracted as instrumental variables, and a large GWAS data of asthma was used to test effects of the metabolites on this outcome. The inverse-variance weighted method was used for primary MR analysis. The weighted median, MR-Egger regression, MR-PRESSO, and leave-one-out analyses were utilized to evaluate heterogeneity and pleiotropy. Potential confounders were adjusted by performing multivariable MR analyses. Reverse MR analysis was also conducted to estimate the causal effect of asthma on candidate fatty acid metabolites. Further, we performed colocalization analysis to examine the pleiotropy of variants within the fatty acid desaturase 1 (FADS1) locus between the significant metabolite traits and the risk of asthma. Cis-eQTL-MR and colocalization analysis were also performed to determine the association between RNA expression of FADS1 and asthma.

RESULTS

Genetically instrumented higher average number of methylene groups was causally associated with a lower risk of asthma in primary MR analysis, while inversely, the higher ratio of bis-allylic groups to double bonds and the higher ratio of bis-allylic groups to total fatty acids, were associated with higher probabilities of asthma. Consistent results were obtained in multivariable MR when adjusted for potential confounders. However, these effects were completely eliminated after SNPs correlated with the FADS1 gene were excluded. The reverse MR also found no causal association. The colocalization analysis suggested that the three candidate metabolite traits and asthma likely share causal variants within the FADS1 locus. In addition, the cis-eQTL-MR and colocalization analyses demonstrated a causal association and shared causal variants between FADS1 expression and asthma.

CONCLUSIONS

Our study supports a negative association between several PUFA traits and the risk of asthma. However, this association is largely attributed to the influence of FADS1 polymorphisms. The results of this MR study should be carefully interpreted given the pleiotropy of SNPs associated with FADS1.

Physical activity mediates the effect of education on mental health trajectories in older age

OBJECTIVE

Why people with lower levels of educational attainment have poorer mental health than people with higher levels can partly be explained by financial circumstances. However, whether behavioral factors can further explain this association remains unclear. Here, we examined the extent to which physical activity mediates the effect of education on mental health trajectories in later life.

METHODS

Data from 54,818 adults 50 years of age or older (55 % women) included in the Survey of Health, Aging and Retirement in Europe (SHARE) were analyzed using longitudinal mediation and growth curve models to estimate the mediating role of physical activity (baseline and change) in the association between education and mental health trajectories. Education and physical activity were self-reported. Mental health was derived from depressive symptoms and well-being, which were measured by validated scales.

RESULTS

Lower education was associated with lower levels and steeper declines in physical activity over time, which predicted greater increases in depressive symptoms and greater decreases in well-being. In other words, education affected mental health through both levels and trajectories of physical activity. Physical activity explained 26.8 % of the variance in depressive symptoms and 24.4 % in well-being, controlling for the socioeconomic path (i.e., wealth and occupation).

CONCLUSIONS

These results suggest that physical activity is an important factor in explaining the association between low educational attainment and poor mental health trajectories in adults aged 50 years and older.

The Association Between Regular Physical Activity and Depressive Symptoms Among Patients in Treatment of Alcohol and Substance Use Disorders

Background

Alcohol and other substance use disorders and major depression often co-occur. A sedentary lifestyle is related to major depression and even moderate exercise may prevent and contribute to the treatment of depression. Studies have found an effect of physical activity on depression in alcohol and other substance use disorder patients even in clinical settings.

Aim

To investigate the relationship between level of physical activity and depressive symptoms over time in alcohol and substance use disorder inpatients.

Methods

Eighty-nine substance use disorder inpatients were followed for 6 months during treatment. The International Physical Activity Questionnaire was used to categorize 3 groups of low, moderate, or high level of physical activity. In addition to background variables and alcohol and drug use measures, data on biometric measures and on sleep were gathered. Becks Depression Inventory version II (BDI-II) measured depressive symptoms. A multilevel logistic regression was used to analyze the longitudinal relationship between physical activity and depressive symptoms.

Results

Most patients (57%) reported low activity, while 24% reported moderate and 19% high activity. Few changed their activity level during treatment. Moderate physical activity was related to lower score on BDI-II (P = .029). Level of physical activity was closely related to insomnia (P = .024). In the multivariate analysis the relationship between depressive symptoms and physical activity did not withstand the adjustment for insomnia. However, in the multilevel logistic regression higher physical activity was related to lower BDI-II score in a dose dependent manner.

Conclusions

Among these alcohol and other substance use disorders patients in treatment, there was a relationship between depressive symptoms and physical activity. The low level of physical activity identified among these patients was related to a high level of depressive symptoms. The level of depressive symptoms declined over time; but this change was not related to an increase in physical activity.

Nutrient Inadequacy in Korean Young Adults with Depression: A Case Control Study

The role of diet is gaining attention among the modifiable factors associated with depression; thus, this case-control study examined the association between nutrition and depression in young Korean adults. Dietary surveys in individuals with depression (n = 39) and age- and gender-matched controls (n = 76) were conducted using food records and food frequency questionnaires. Men with depression consumed less mushrooms and meat, while women consumed significantly less grains (p < 0.05). Overall, the depression group consumed less energy and nutrients, and the difference was more pronounced in men. The male depression group had lower nutrient adequacy ratio (NAR) for energy, protein, vitamin A, thiamine, niacin, folate, and phosphorus, whereas the female depression group had lower NARs for energy, protein, niacin, and vitamin B₁₂. The depression group had a significantly lower mean adequacy ratio in both genders. Furthermore, the proportion of inappropriate nutrient intake was higher in both genders of the depression group, exhibiting significant differences in energy, protein, niacin, folate, and zinc in men and energy, riboflavin, folate, and vitamin C in women. Hence, both men and women in the depression group had poor nutrient intake and high rates of nutrient inadequacy and improper consumption. This suggests that the quantity and quality of meals should be improved for individuals with depressive symptoms.

Neurobiological, Psychosocial, and Behavioral Mechanisms Mediating Associations Between Physical Activity and Psychiatric Symptoms in Youth in the Netherlands

Importance

Understanding the mechanisms by which physical activity is associated with a lower risk of psychiatric symptoms may stimulate the identification of cost-efficient strategies for preventing and treating mental illness at early life stages.

Objective

To examine neurobiological, psychosocial, and behavioral mechanisms that mediate associations of physical activity with psychiatric symptoms in youth by testing an integrated model.

Design, setting, and participants

Generation R is an ongoing prospective population-based cohort study collecting data from fetal life until young adulthood in a multiethnic urban population in the Netherlands. Pregnant women living in Rotterdam with an expected delivery date between April 2002 and January 2006 were eligible for participation along with their children born during this time. Data were collected at a single research center in the Erasmus Medical Center Sophia Children's Hospital. For the current study, data were analyzed from 4216 children with complete data on both exposure and outcome at ages 6, 10, and 13 years. Data were analyzed from January 2021 to November 2022.

Exposures

Physical activity was ascertained at age 6 years (visit 1) via parent report and included weekly frequency and duration of walking or cycling to or from school, physical education at school, outdoor play, swimming, and sports participation.

Main Outcomes and Measures

Psychiatric symptoms (internalizing and externalizing symptoms) were assessed at age 6 years (visit 1) and at age 13 years (visit 3) using the Child Behavior Checklist. Several mechanisms were explored as mediators, measured at age 10 years (visit 2). Neurobiological mechanisms included total brain volume, white matter microstructure, and resting-state connectivity assessed using a 3-T magnetic resonance imaging scanner. Psychosocial mechanisms included self-esteem, body image, and friendship. Behavioral mechanisms included sleep quality, diet quality, and recreational screen time. Pearson correlations between physical activity measures and psychiatric symptoms were calculated, with false discovery rate correction applied to account for the number of tests performed. Mediation analyses were performed when a correlation (defined as false discovery rate P < .05) between exposure and outcome was observed and were adjusted for confounders.

Results

Among the 4216 children included in this study, the mean (SD) age was 6.0 (0.4) years at visit 1, and 2115 participants (50.2%) were girls. More sports participation was associated with fewer internalizing symptoms (β for direct effect, -0.025; SE, 0.078; P = .03) but not externalizing symptoms. Self-esteem mediated the association between sports participation and internalizing symptoms (β for indirect effect, -0.009; SE, 0.018; P = .002). No evidence was found for associations between any other neurobiological, psychosocial, or behavioral variables. No association was found between other types of physical activity and psychiatric symptoms at these ages.

Conclusions and Relevance

The integrated model presented in this cohort study evaluated potential mechanisms mediating associations between physical activity and psychiatric symptoms in youth. Self-esteem mediated an association between sports participation in childhood and internalizing symptoms in adolescence; other significant mediations were not observed. Further studies might explore whether larger effects are present in certain subgroups (eg, children at high risk of developing psychiatric symptoms), different ages, or structured sport-based physical activity interventions.

Efficacy of an mHealth Behavior Change Intervention for Promoting Physical Activity in the Workplace: Randomized Controlled Trial

BACKGROUND

Insufficient physical activity (PA) is a well-established risk factor for several noncommunicable diseases such as cardiovascular diseases, cancer, diabetes, depression, and dementia. The World Health Organization (WHO) advises that individuals engage in 150 minutes of moderate PA per week or 75 minutes of intense PA per week. According to the WHO's latest report, 23% of adults fail to meet the minimum recommended level of PA. The percentage was even higher in a recent global study that showed 27% of adults were insufficiently active and reported a 5% increase in the prevalence trend of insufficient PA between 2001 and 2016. The study also showed the rate of insufficient PA among countries varied significantly. For instance, it was estimated that 40% were insufficiently active in the United States, and the percentage was even higher in Saudi Arabia (more than 50%). Governments are actively developing policies and methods to successfully establish a PA-inducing environment that encourages a healthy lifestyle in order to address the global steady decline in PA.

OBJECTIVE

The purpose of this study was to determine the effectiveness of mobile health (mHealth) interventions, particularly SMS text messaging interventions, to improve PA and decrease BMI in healthy adults in the workplace.

METHODS

In this parallel, 2-arm randomized controlled trial, healthy adults (N=327) were randomized to receive an mHealth intervention (tailored text messages combined with self-monitoring (intervention; n=166) or no intervention (control; n=161). Adults who were fully employed in an academic institution and had limited PA during working hours were recruited for the study. Outcomes, such as PA and BMI, were assessed at baseline and 3 months later.

RESULTS

Results showed significant improvement in PA levels (weekly step counts) in the intervention group (β=1097, 95% CI 922-1272, P<.001). There was also a significant reduction in BMI (β=0.60, 95% CI 0.50-0.69, P<.001).

CONCLUSIONS

Combining tailored text messages and self-monitoring interventions to improve PA and lower BMI was significantly effective and has the potential to leverage current methods to improve wellness among the public.

The associations of physical activity and lifetime depression with all-cause and cause-specific mortality: evidence from a prospective cohort study

This study aims to explore the joint associations of physical activity and lifetime depression with all-cause and cause-specific mortality. The present study using data from UK Biobank, included 316568 participants aged 37 to 73 years recruited from 22 centers between 2006 and 2010. Total physical activity (TPA), moderate-to-vigorous physical activity (MVPA) and vigorous physical activity (VPA), assessed by metabolic equivalent task (MET) were used and Cox-proportional hazard models were performed in this study. The incidence rate of all-cause, CVD, and cancer mortality was 4.35(95%CI: 4.29-4.42), 0.69 (95%CI: 0.67-0.72), and 2.23 (95%CI: 2.19-2.28) per 1000 person-years after an average follow-up time of 12.49 years. Lower levels of TPA, MVPA, and VPA were all independently associated with elevated risk of all-cause and cancer mortality. Lifetime depression was significantly associated with increased risk of all-cause (HR=1.46, 95%CI: 1.40-1.52), CVD (HR=1.48, 95%CI: 1.33-1.64), and cancer mortality (HR=1.13, 95%CI: 1.06-1.21). Significant interactive effect of low levels of TPA, MVPA, and VPA and lifetime depression on all-cause mortality were found in this study. The risk of all-cause mortality associated with lifetime depression was deteriorated with low levels of physical activity. Relevant interventions for regular PA should be performed among depressed population.

Multiomic approach and Mendelian randomization analysis identify causal associations between blood biomarkers and subcortical brain structure volumes

Alterations in subcortical brain structure volumes have been found to be associated with several neurodegenerative and psychiatric disorders. At the same time, genome-wide association studies (GWAS) have identified numerous common variants associated with brain structure. In this study, we integrate these findings, aiming to identify proteins, metabolites, or microbes that have a putative causal association with subcortical brain structure volumes via a two-sample Mendelian randomization approach. This method uses genetic variants as instrument variables to identify potentially causal associations between an exposure and an outcome. The exposure data that we analyzed comprised genetic associations for 2,994 plasma proteins, 237 metabolites, and 103 microbial genera. The outcome data included GWAS data for seven subcortical brain structure volumes including accumbens, amygdala, caudate, hippocampus, pallidum, putamen, and thalamus. Eleven proteins and six metabolites were found to have a significant association with subcortical structure volumes. We found causal associations between amygdala volume and granzyme A as well as association between accumbens volume and plasma protease c1 inhibitor. Among metabolites, urate had the strongest association with thalamic volume. No significant associations were detected between the microbial genera and subcortical brain structure volumes. We also observed significant enrichment for biological processes such as proteolysis, regulation of the endoplasmic reticulum apoptotic signaling pathway, and negative regulation of DNA binding. Our findings provide insights to the mechanisms through which brain volumes may be affected in the pathogenesis of neurodevelopmental and psychiatric disorders and point to potential treatment targets for disorders that are associated with subcortical brain structure volumes.

Assessment of bidirectional relationships between depression and rheumatoid arthritis among adults: a two-sample Mendelian randomization study

OBJECTIVE

Increasing evidence shows that depression is associated with rheumatoid arthritis (RA). However, the causality and direction of this association remain unclear, because links between the two diseases might be caused by shared environmental confounding factors. Our study aims to understand a putative causal link between the two diseases.

METHODS

We retrieved summary statistics from meta-analyses of non-overlapping genome-wide association studies (GWASes) for depression (n = 807,553, 246,363 cases and 561,190 controls) and RA (n = 58,284, 14,361 cases and 42,923 controls). We combined Mendelian randomization (MR) estimates from each genetic instrument using inverse-variance weighted (IVW) meta-analysis, with alternate methods (e.g., simple median approach, weighted median approach, and MR-Egger regression) and conducted sensitivity analyses to assess the robustness of MR analyses.

RESULTS

We found no evidence of causal relationships between depression and RA across all MR methods (IVW OR, 1.028 for RA; 95% CI, 0.821-1.287; P = 0.810) or vice versa (IVW OR, 0.999 for depression; 95% CI, 0.984-1.014; P = 0.932), indicating the links between the two diseases might be due to confounders.

CONCLUSION

Despite the results, to optimize treatment outcomes of RA patients, we still emphasize depression should be managed as part of routine clinical care to optimize treatment outcomes of RA.

Genetic support of a causal relationship between cannabis use and educational attainment: a two-sample Mendelian randomization study of European ancestry

BACKGROUND AND AIMS

Excessive cannabis use may lead to lower educational attainment. However, this association may be due to confounders and reverse causality. We tested the potential causal relationship between cannabis use disorder (CUD) or life-time cannabis use (LCU) and educational attainment.

DESIGN

Bidirectional two-sample Mendelian randomization (MR) study was conducted. Our primary method was inverse-variance weighted (IVW) MR, with a series of sensitivity analyses. Multivariable MR (MVMR) was performed to estimate any direct effect independent of intelligence, smoking initiation or attention deficit hyperactivity disorder (ADHD).

SETTING AND PARTICIPANTS

European ancestry individuals. The sample sizes of the genome-wide association study ranged from 55 374 to 632 802 participants.

MEASUREMENTS

Genetic variants of CUD, LCU or educational attainment.

FINDINGS

Using univariable MR, we found evidence of a potential causal effect of genetic liability to CUD on a lower educational attainment [MR, 95% confidence interval (CI)_{inverse variance weighted (IVW)}  = -1.2 month (-1.9 month, -0.5 month); P = 0.0008]. However, we found no evidence of an effect of genetic liability to LCU on educational attainment [MR, 95% CI_IVW  = 0.5 month (-1.5 month, 2.6 month), P = 0.6032]. Reverse direction analysis suggested that genetic liability to higher educational attainment had a potential causal effect on lower risk of CUD [odds ratio (OR), 95% CI_IVW  = 0.39 (0.29, 0.52), P = 1.69 × 10^-10 ]. We also found evidence of potential causal effect from genetic liability to higher educational attainment to higher risk of LCU [OR, 95% CI_IVW  = 1.35 (1.11, 1.66), P = 0.0033].

CONCLUSIONS

Genetic liability to cannabis use disorder may lead to lower educational attainment. Genetic liability to higher educational attainment may also lead to higher life-time cannabis use risk and lower cannabis use disorder risk. However, the bidirectional effect between cannabis use disorder and educational attainment may be due to shared risk factors (e.g. attention-deficit hyperactivity disorder).

Genetic correlation and gene-based pleiotropy analysis for four major neurodegenerative diseases with summary statistics

Recent genome-wide association studies suggested shared genetic components between neurodegenerative diseases. However, pleiotropic association patterns among them remain poorly understood. We here analyzed 4 major neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), and found suggestively positive genetic correlation. We next implemented a gene-centric pleiotropy analysis with a powerful method called PLACO and detected 280 pleiotropic associations (226 unique genes) with these diseases. Functional analyses demonstrated that these genes were enriched in the pancreas, liver, heart, blood, brain, and muscle tissues; and that 42 pleiotropic genes exhibited drug-gene interactions with 341 drugs. Using Mendelian randomization, we discovered that AD and PD can increase the risk of developing ALS, and that AD and ALS can also increase the risk of developing FTD, respectively. Overall, this study provides in-depth insights into shared genetic components and causal relationship among the 4 major neurodegenerative diseases, indicating genetic overlap and causality commonly drive their co-occurrence. It also has important implications on the etiology understanding, drug development and therapeutic targets for neurodegenerative diseases.

Genetic insights into the causal relationship between physical activity and cognitive functioning

Physical activity and cognitive functioning are strongly intertwined. However, the causal relationships underlying this association are still unclear. Physical activity can enhance brain functions, but healthy cognition may also promote engagement in physical activity. Here, we assessed the bidirectional relationships between physical activity and general cognitive functioning using Latent Heritable Confounder Mendelian Randomization (LHC-MR). Association data were drawn from two large-scale genome-wide association studies (UK Biobank and COGENT) on accelerometer-measured moderate, vigorous, and average physical activity (N = 91,084) and cognitive functioning (N = 257,841). After Bonferroni correction, we observed significant LHC-MR associations suggesting that increased fraction of both moderate (b = 0.32, CI95% = [0.17,0.47], P = 2.89e - 05) and vigorous physical activity (b = 0.22, CI95% = [0.06,0.37], P = 0.007) lead to increased cognitive functioning. In contrast, we found no evidence of a causal effect of average physical activity on cognitive functioning, and no evidence of a reverse causal effect (cognitive functioning on any physical activity measures). These findings provide new evidence supporting a beneficial role of moderate and vigorous physical activity (MVPA) on cognitive functioning.

The Association between Physical Activity and Intrinsic Capacity in Chinese Older Adults and Its Connection to Primary Care: China Health and Retirement Longitudinal Study (CHARLS)

BACKGROUND

In 2015, intrinsic capacity (IC) was proposed by the WHO as a new measure for healthy aging. Evidence has shown that physical activity (PA) benefits the physical and mental health of older adults. However, the association between PA and IC among older adults was not well evaluated or reported. This study aims to investigate the association between PA and general and specific IC among Chinese older adults.

METHOD

The study included individuals aged 60 and above from the China Health and Retirement Longitudinal Study in 2015. The IC scores were constructed based on the WHO concept of five domains: psychological capacity, cognition, locomotion, vitality, and sensory abilities. Total PA and leisure PA were measured based on different activity purposes. Linear mixed-effects models and generalized linear mixed-effects models were developed to assess the associations between PA and IC.

RESULTS

A total of 3359 participants were included in this study. Older adults who reported some PA were associated with a higher composite IC score, with a mean difference of 0.14 (95% CI: 0.09-0.18, p < 0.001) compared to those who reported no PA. In terms of leisure PA, physically active adults had a higher composite IC score with a mean difference of 0.06 (95% CI: 0.03-0.09, p < 0.001). Older adults with a high level of leisure PA also had a significantly higher composite IC score (diff. in mean = 0.07, 95% CI: 0.01-0.13, p < 0.05) compared to those with low-level leisure PA. In addition, PA was positively and significantly associated with three specific IC domains: locomotion, cognition, and vitality.

CONCLUSIONS

Improving both general and leisure PA can be an effective way to prevent the decline in IC among older adults, thus reducing the personal and public load of primary healthcare for aging countries such as China.

Mediating Effects of Trait Anxiety and State Anxiety on the Effects of Physical Activity on Depressive Symptoms

BACKGROUND

Previous studies have reported that physical activity can prevent the onset of depression and reduces anxiety. In the present study, the hypothesis that total physical activity time influences depressive symptoms via state and trait anxiety was tested by a path analysis.

METHODS

Self-administered questionnaires were used to survey 526 general adult volunteers from April 2017 to April 2018. Demographic information, physical activity, and state and trait anxiety were investigated.

RESULTS

The association between physical activity time and depressive symptoms was expressed as a U-shape curve. The results of the covariance structure analysis showed that differences from the optimal physical activity time (DOT) had direct positive effects on state and trait anxiety. DOT affected depressive symptoms only via trait anxiety, and this was a complete mediation model.

CONCLUSION

The present study suggests that an optimal physical activity time exists for depressive symptoms. The path model demonstrated an association between the three factors of optimal physical activity time, trait anxiety, and depressive symptoms, and the effect was fully mediated by trait anxiety.

The relationship between physical activity pre COVID-19 pandemic with mental health, depression, and anxiety in COVID-19 patients: a cross-sectional study

Purpose

Covid-19 pandemic has gained a growing trend and affected mental health in several aspects. Physical activity guidelines was strongly associated with a reduced risk for severe COVID-19 outcomes among infected adults. The purpose of this study was to evaluate the association between physical activity pre COVID-19 pandemic with mental health, depression, and anxiety in COVID-19 patients.

Methods

206 hospitalized patients diagnosed with covid-19 (140 male and 66 female, aged 34.5 ± 12) were selected and completed physical activity questionnaire (IPAQ) and hospital anxiety and depression questionnaire (HADS). For physical activity status assessment, a self-completed IPAQ questionnaire was taken and patients were divided into: (1) low active, (2) moderate active and (3) high active groups according to their physical activity experience. One-way ANOVA test was recruited and Tukey post hoc test was taken to assess difference among means. Pearson correlation was used to evaluate the association between physical activity level and mental health status (p < 0.05).

Results

The results from this study showed that anxiety and depression was significantly higher in low active patients (p = 0.001) and there was a negative correlation between physical activity level and HADS (p = 0.001). However, patients with high physical activity pre COVID-19 pandemic have a lowest levels of anxiety and depression compare to other groups (p < 0.001).

Conclusion

It seems that adequate physical activity as a part of a healthy lifestyle may have a beneficial effect on mental health during the current outbreak of covid-19. Therefore, it is suggested that we perform exercise training every day to preconditioning effects.

Disentangling the relationship between depression and chronic widespread pain: A Mendelian randomisation study

OBJECTIVE

Depression and chronic widespread pain (CWP) frequently coexist, but whether depression is an independent causal risk factor for CWP, and/or vice versa, remains unclear. We investigated the bidirectional causal relationship between depression and CWP.

METHODS

We performed a two-sample Mendelian randomisation (MR) study to estimate the causal relationship between genetically predicted depression (170,756 cases, 329,443 controls) and risk of CWP (6,914 cases, 242,929 controls), and the effect of CWP on depression susceptibility, using large population-level genetic data. We used a new MR method, Causal Analysis Using Summary Effect estimates (CAUSE), which allows for sample overlap, in addition to traditional MR and sensitivity analyses.

RESULTS

For each doubling in odds of genetic liability to depression, the risk of chronic widespread pain was increased (OR 1.004, 95% credible interval 1.003-1.005; p = 7.3 × 10^-5 that the causal model is a better fit than non-causal model). There was bidirectional evidence of causality, with genetic liability to chronic widespread pain increasing depression susceptibility (OR 2.31; 95%CrI 1.57, 3.40; p = 0.0026 that the causal model is a better fit). Other MR methods produced concordant results.

CONCLUSIONS

This study provides evidence in support of a bidirectional causal relationship between depression and increased risk of chronic widespread pain, whilst overcoming the major limitations of previous epidemiological studies. Interventions for depression may be an effective strategy to prevent or reduce the burden of chronic widespread pain and vice versa.

Causal relationship between human blood omega-3 fatty acids and the risk of epilepsy: A two-sample Mendelian randomization study

Background

Though omega-3 fatty acids reduce seizures in several animal models, considerable controversy exists regarding the association between omega-3 fatty acids and epilepsy in human.

Objective

To assess whether genetically determined human blood omega-3 fatty acids are causally associated with the risk of epilepsy outcomes.

Methods

We conducted a two-sample Mendelian randomization (MR) analysis by applying summary statistics of genome-wide association study datasets of both exposure and outcomes. Single nucleotide polymorphisms significantly associated with blood omega-3 fatty acids levels were selected as instrumental variables to estimate the causal effects on epilepsy. Five MR analysis methods were conducted to analyze the final results. The inverse-variance weighted (IVW) method was used as the primary outcome. The other MR analysis methods (MR-Egger, weighted median, simple mode, and weighted mode) were conducted as the complement to IVW. Sensitivity analyses were also conducted to evaluate heterogeneity and pleiotropy.

Results

Genetically predicted the increase of human blood omega-3 fatty acids levels was associated with a higher risk of epilepsy (OR = 1.160, 95%CI = 1.051–1.279, P = 0.003).

Conclusions

This study revealed a causal relationship between blood omega-3 fatty acids and the risk of epilepsy, thus providing novel insights into the development mechanism of epilepsy.

Internet addiction and depressive symptoms: a dose-response effect mediated by levels of physical activity

INTRODUCTION

There are several negative impacts on the physical and mental health of people presenting internet addiction, including development of mood disorders, such as depression.

OBJECTIVE

The aim of the study was to evaluate the association between internet addiction and depressive symptoms, as well as to test the mediating role of physical activity in this association.

METHODS

A cross-sectional study was conducted with undergraduate students from three universities (one private and two public institutions) in southern Brazil. Depressive symptoms were measured with the Beck Depression Inventory (BDI-21), internet addiction with the Internet Addiction Test (IAT-20), and physical activity with the International Physical Activity Questionnaire (IPAQ - short version). Poisson regression and the Karlson-Holm-Breen mediation method were used for statistical analyses.

RESULTS

We observed a dose-response relationship between internet addiction and depressive symptoms. Levels of physical activity mediated the association between moderate internet addiction and depressive symptoms, accounting for 10.7% of the effect observed.

CONCLUSION

Internet addiction can be detrimental to individuals' health, contributing to development of depressive symptoms. Along with psychological and pharmacological therapies, prescription of physical activities is recommended.

Association of urinary heavy metals co-exposure and adult depression: Modification of physical activity

OBJECTIVE

This study aimed to evaluate the association between urinary heavy metal mixture exposure and depression, and the modifying role of physical activity in the effects of heavy metal mixture on depression risk was also considered.

METHODS

Data of this study were derived from the National Health and Nutrition Examination Survey 2011-2016. Depression was measured by the Patient Health Questionnaire. We first selected 6 (cadmium, cobalt, tin, antimony, thallium, and mercury) from 14 heavy metals through elastic net regression for further analysis. Then binomial logistic regression, generalized additive model, environment risk score (ERS), and weighted quantile sum (WQS) regression were adopted to assess the effects of six metals individual and cumulative exposure on depression risk. Finally, we also examined whether physical activity could mitigate the effects of heavy metal co-exposure on depression risk.

RESULTS

Totally, 4212 participants were included and 7.40% of subjects were with depression. We found urinary tin and antimony were separately associated with increased odds of depression (Sb: OR = 1.285, 95% CI: 1.064-1.553; Sn: OR = 1.281, 95% CI: 1.097-1.495), and a linear dose-response relationship between tin and depression was also noticed (P < 0.05). Meanwhile, urinary heavy metals co-exposure was positively related to depression risk (ERS_Q4: OR = 2.691, 95% CI: 1.399-5.174; WQS_positive: OR = 1.465, 95% CI: 1.063-2.021), in which tin, antimony, and cadmium were identified with greater contributions to the overall mixture effect. In both ERS and WQS models, the significant positive association between the metal mixture and depression risk remained only in those who were inactive in physical activity.

CONCLUSION

Our study concluded the detrimental effect of heavy metals in combined exposure on the risk of depression, which might be attenuated by physical activity.

Genetic susceptibility and lifestyle modify the association of long-term air pollution exposure on major depressive disorder: a prospective study in UK Biobank

BACKGROUND

Evidence linking air pollution to major depressive disorder (MDD) remains sparse and results are heterogeneous. In addition, the evidence about the interaction and joint associations of genetic risk and lifestyle with air pollution on incident MDD risk remains unclear. We aimed to examine the association of various air pollutants with the risk of incident MDD and assessed whether genetic susceptibility and lifestyle influence the associations.

METHODS

This population-based prospective cohort study analyzed data collected between March 2006 and October 2010 from 354,897 participants aged 37 to 73 years from the UK Biobank. Annual average concentrations of PM_2.5, PM₁₀, NO₂, and NO_x were estimated using a Land Use Regression model. A lifestyle score was determined based on a combination of smoking, alcohol drinking, physical activity, television viewing time, sleep duration, and diet. A polygenic risk score (PRS) was defined using 17 MDD-associated genetic loci.

RESULTS

During a median follow-up of 9.7 years (3,427,084 person-years), 14,710 incident MDD events were ascertained. PM_2.5 (HR: 1.16, 95% CI: 1.07-1.26; per 5 μg/m³) and NO_x (HR: 1.02, 95% CI: 1.01-1.05; per 20 μg/m³) were associated with increased risk of MDD. There was a significant interaction between the genetic susceptibility and air pollution for MDD (P-interaction < 0.05). Compared with participants with low genetic risk and low air pollution, those with high genetic risk and high PM_2.5 exposure had the highest risk of incident MDD (PM_2.5: HR: 1.34, 95% CI: 1.23-1.46). We also observed an interaction between PM_2.5 exposure and unhealthy lifestyle (P-interaction < 0.05). Participants with the least healthy lifestyle and high air pollution exposures had the highest MDD risk when compared to those with the most healthy lifestyle and low air pollution (PM_2.5: HR: 2.22, 95% CI: 1.92-2.58; PM₁₀: HR: 2.09, 95% CI: 1.78-2.45; NO₂: HR: 2.11, 95% CI: 1.82-2.46; NO_x: HR: 2.28, 95% CI: 1.97-2.64).

CONCLUSIONS

Long-term exposure to air pollution is associated with MDD risk. Identifying individuals with high genetic risk and developing healthy lifestyle for reducing the harm of air pollution to public mental health.