Physical frailty and the risk of major depressive disorder: The Irish Longitudinal Study on Ageing

Exploring the shared genetic basis of major depressive disorder and frailty

BACKGROUND

Major depressive disorder (MDD) and frailty impose substantial health and economic burdens. MDD is recognized as a significant risk factor for frailty, but the genetic associations between these conditions remain unclear. This study investigates the genetic correlation, shared pleiotropic loci, causal relationships, and comorbid genes between MDD and frailty.

METHODS

The genetic correlation between MDD and frailty was assessed using linkage disequilibrium score regression (LDSC) based on data from genome-wide association studies (GWAS). A detailed analysis was performed to identify shared pleiotropic loci and causal relationships through cross-phenotype association tests and Mendelian randomization. Additionally, tissue enrichment analysis was conducted using stratified LDSC, gene-based associations with both conditions were assessed using Multimarker Analysis of Genomic Annotation (MAGMA), and pathway analysis of comorbid genes was performed using the g: GOSt tool.

RESULTS

Our findings revealed a significant positive genetic correlation between MDD and frailty (rg = 0.65, P = 1.49E-219). We identified 57 shared risk SNPs between the two conditions, including 6 novel SNPs. Mendelian randomization analyses indicated robust causal effects of MDD on frailty and vice versa. Furthermore, we observed tissue-specific heritability enrichment in 9 brain tissues. By combining MAGMA and CPASSOC analyses, we identified 10 comorbid genes associated with both MDD and frailty, primarily involved in synapse formation, modulation, plasticity, and desaturase activity.

CONCLUSION

This study provides strong evidence for a shared genetic basis between MDD and frailty. The identification of comorbid genes offers new insights into the mechanisms underlying the relationship between these conditions.

Effects of Social Support Provided by Disabled Older Adults to Others on Their Own Depressive Symptoms: A Moderated Mediation Model

Purpose

While previous studies have extensively examined the impact of receiving positive social support during social support interactions on depressive symptoms among older adults, adverse effects experienced, such as being rejected or ignored, are often overlooked. Moreover, there has been limited discussion on the effects of giving social support to others. Thus, this study investigates the impacts of social support given by disabled older adults to others on their own depressive symptoms, as well as the mediating role of receiving social support (both positive and negative aspects) and the moderating effect of the activity of daily living (ADL).

Patients and Methods

This cross-sectional, community-based study was conducted in Wenzhou and Jiaxing City, China, from September 2021 to September 2022, with a total of 255 disabled older adults meeting the inclusion and exclusion criteria. The data were collected face-to-face using a structured questionnaire. The participants were asked to complete the Barthel Index Scale, the Chinese version of the Positive and Negative Social Exchange Scale, the Giving Social Support questionnaire, and the Short Form Chinese Geriatric Depression Scale to measure disability, receiving positive and negative social support, giving social support, and depressive symptoms, respectively. Descriptive statistical analysis, correlation analysis, mediation effect tests, and moderation effect tests were used to analyse the questionnaire data.

Results

The social support provided by disabled older adults to others primarily involved companionship and care. The positive aspect of social support received was largely emotional support, while the negative aspect was mainly characterised by failure to obtain help and unsympathetic behaviour. Providing social support was found to be associated with a potential beneficial effect on depressive symptoms, linked to lower severity, with this effect fully mediated by receiving social support. Specifically, receiving emotional support accounted for 56.63% of the effect size, while failure to obtain help and unsympathetic behaviour contributed 21.55%, and rejection and neglect collectively accounted for 21.83%. Additionally, the effect was partially moderated by ADL, with older adults exhibiting lower ADL scores showing a greater benefit from both giving and receiving social support compared to those with higher ADL scores.

Conclusion

It is imperative to recognise and encourage disabled older adults to provide social support to others, especially emotional support, while reducing negative feedback, such as neglect and unnecessary blame. This could alleviate their depressive symptoms and promote psycho-social well-being.

Bidirectional causal associations between aging and major mental disorders: A population-based study using the two-sample mendelian randomization method from the UK biobank (AM-SRNMA 002)

AIMS

While observational studies have suggested associations linking aging and mental disorders, the question of causality has remained unclear. This study aimed to explore the causal relationship between aging level and major mental disorders.

METHODS

We utilized Two-Sample Mendelian randomization (2SMR) with mental disorders data and aging indicators information from an extensive genome-wide association study (GWAS) database. The GWAS database is a comprehensive resource that compiles genetic association data, encompassing a sample size of over 450,000 individuals. We employed five methods for 2SMR and single nucleotide polymorphisms were chosen as instrumental variables.

RESULTS

Our analyses consistently supported a bidirectional causal association between the Frailty Index (FI) and Major Depressive Disorder (MDD). Furthermore, our findings indicated potential influences, such as Attention-Deficit/Hyperactivity Disorder (ADHD) and Bipolar Disorder (BD) affecting GrimAge, and Anxiety Disorder (AD) impacting Left Hand Grip Strength (LHGS). In contrast, we observed no significant correlations for other mental disorders on FI, Telomere Length (TL), GrimAge, Appendicular Lean Mass (ALM), and LHGS. In the reverse direction, FI showed a significant impact on the risk of MDD, AD, and ADHD, while LHGS affected the risk of MDD. Importantly, no significant associations were found between other factors and the risk of MDD, BD, AD, Schizophrenia (SZ), and ADHD.

CONCLUSIONS

This 2SMR analysis has presented evidence for a bidirectional causal relationship between FI and MDD, while the relationship between ADHD, BD, and GrimAge should be more considered. Our study provides genetic evidence supporting a causal link between aging indicators and several mental illnesses.

Frailty and psychiatric disorders: A bidirectional Mendelian randomization study

BACKGROUND

The association between frailty and psychiatric disorders has been reported in observational studies. However, it is unclear whether frailty facilitates the appearance of psychiatric disorders or vice versa. Therefore, we conducted a bidirectional Mendelian randomization (MR) study to evaluate the causality.

METHODS

Independent genetic variants associated with frailty index (FI) and psychiatric disorders were obtained from large genome-wide association studies (GWAS). The inverse variance weighted method was utilized as the primary method to estimate causal effects, followed by various sensitivity analyses. Multivariable analyses were performed to further adjust for potential confounders.

RESULTS

The present MR study revealed that genetically predicted FI was significantly and positively associated with the risk of major depressive disorder (MDD) (odds ratio [OR] 1.79, 95 % confidence interval [CI] 1.48-2.15, P = 1.06 × 10-9), anxiety disorder (OR 1.61, 95 % CI 1.19-2.18, P = 0.002) and neuroticism (OR 1.38, 95 % CI 1.18-1.61, P = 3.73 × 10-5). In the reverse MR test, genetic liability to MDD (beta 0.232, 95 % CI 0.189-0.274, P = 1.00 × 10-26) and neuroticism (beta 0.128, 95 % CI 0.081-0.175, P = 8.61 × 10-8) were significantly associated with higher FI. Multivariable analyses results supported the causal association between FI and MDD and neuroticism.

LIMITATIONS

Restriction to European populations, and sample selection bias.

CONCLUSIONS

Our study suggested a bidirectional causal association between frailty and MDD neuroticism, and a positive correlation of genetically predicted frailty on the risk of anxiety disorder. Developing a deeper understanding of these associations is essential to effectively manage frailty and optimize mental health in older adults.

Reduced grip strength potentially indicates depression: Investigating multicontinental databases

BACKGROUND

Multi-national studies in the association between handgrip strength and depression in middle and older aged adults are limited. Hence, Brazil, China, Europe, Korea, United Kingdom (UK) and United States (US) datasets were utilized to investigate this association.

METHODS

A cross-sectional study was conducted with 51,285 participants aged >45 years. Handgrip strength scores were divided into quartiles, groups 1 (highest) to 4 (lowest) in each database, and depression measures converted to binary scores.

RESULTS

Males in China and UK reported higher adjusted odds ratios (aORs) of depression for groups 2, 3, and 4 than for group 1. Brazil, US, and Korea reported greater aORs in groups 3 and 4 whereas Europe demonstrated increased aORs for group 4 only. Among females, China, Brazil, US, and Korea showed high aORs across all groups, while UK and Europe reported increased aORs for group 4 only. Highest ORs were reported from Korea in group 4 for males (aOR: 3·09; 95 % CI: 2·15-4·43; p < 0·001) and females (aOR: 3·74; 95 % CI: 2·78-5·03; p < 0·001). When removing the regional factor, aORs were higher in lower groups, with the highest reported from group 4 for males (aOR: 2·32; 95 % CI: 2·09-2·58; p < 0·001) and females (aOR: 2·11; 95 % CI: 1·95-2·29; p < 0·001).

LIMITATIONS

Being a cross-sectional study, the results were not able to establish the causal direction between handgrip strength and depression.

CONCLUSION

Lower handgrip strength was associated with an increased likelihood of depression. Early assessment of handgrip strength may identify populations at-risk for depression among middle and older aged adults.

The effect of perceived social support on frailty and depression: A multicategorical multiple mediation analysis

The mediating effects of three sources of perceived social support on frailty severity and depression were examined. Conducted in rural China, data on 570 frail older women were studied. Results showed that significant others' support (mainly daughters) (β = 0.177 for frailty score = 3) mediated the relationship between frailty severity and depression, and the 95 % bias-corrected bootstrap confidence intervals did not straddle zero (0.013-0.419), while the mediating effects of family support (mainly sons) and friends support were not observed. Support from daughters contributes to frail mothers' mental health.

Association Between Frailty-Related Factors and Depression among Older Adults

OBJECTIVES

We analyzed the association between individual frailty-related factors and depression in older adults.

METHODS

A total of 796 older adults who underwent geriatric assessments were included in this cross-sectional study. The frailty-related factors studied were grip strength, physical activity, walking speed, weight loss, and recurrent falls. Depression was based on the Geriatric Depression Scale.

RESULTS

After adjustment for covariates, recurrent falls were associated with depression in males (OR 3.84, 95% CI 1.30-11.35). Among females, weakest grip strength, slow walking speed, and weight loss were associated with depression (OR 2.61, 95% CI 1.52-4.49; OR 1.78, 95% CI 1.02-3.11; and OR 2.52, 95% CI 1.17-5.44, respectively). Having more frailty-related factors was also associated with higher odds of depression.

CONCLUSIONS

The associations between individual frailty-related factors and depression differed among males and females. Further prospective studies on depression and individual frailty-related factors by sex may help elucidate specific targets to be prioritized for clinical assessment and intervention.

CLINICAL IMPLICATIONS

Older adults affected by depression and frailty may present different clinical manifestations based on sex, and require different treatment approaches. Clinicians should assess both physical and psychological needs for integrated care in frail older adults.

Depression among older adults with gastrointestinal malignancies

BACKGROUND

Depression among older adults with cancer is under recognized and under treated. This study characterizes the burden of depression in older adults with gastrointestinal (GI) malignancies prior to chemotherapy and its relationship with geriatric assessment (GA) domains, health-related quality of life (HRQOL), and self-reported healthcare utilization.

METHODS

Patients ≥60 years in GI oncology clinics at UAB were asked to complete a GA entitled the Cancer & Aging Resilience Evaluation (CARE). We examined depression using the Patient-Reported Outcomes Measurement Information System (PROMIS®) Depression four-item short form; moderate/severe depression was defined by a t-score ≥ 60. Multivariate analysis was used to examine associations between those with and without moderate/severe depression.

RESULTS

Of 355 included patients, 46 had mild depression (13%) and an additional 46 patients had moderate/severe depression (13%). After adjustment for age, sex, education, cancer type, and cancer stage, those who reported moderate/severe depression had a significantly increased odds of reporting falls (adjusted odds ratio [aOR] 4.01, 95% confidence interval [CI] 1.94-8.26), dependence in IADLs (aOR 7.06,CI 2.91-17.1), dependence in ADLs (aOR 6.23, CI 2.89-13.4), malnutrition (aOR 5.86, CI 2.40-14.3), frailty (aOR 13.7, CI 5.80-32.1), and fatigue (aOR 11.2, CI 3.31-37.6). Moderate/severe depression was also significantly associated with worse physical (aOR 7.58, CI 3.30-17.4) and mental (aOR 26.3, CI 10.1-68.8) HRQOL sub-scores, without significant differences in healthcare utilization.

CONCLUSIONS

More than one out of eight older adults with a GI malignancy reported moderate/severe depression prior to chemotherapy, which was associated with impairments in several GA domains and HRQOL.

Frailty and depression: Reciprocal influences or common causes?

BACKGROUND

Previous research demonstrated substantial associations between frailty and depression in late life, but it remains unclear whether this relationship is best explained by reciprocal influences of these variables or by common causes. This study investigated the interdependencies between frailty and depression across time by examining cross-lagged effects within individuals, while accounting for variability in baseline levels and long-term development between individuals.

METHODS

We modeled longitudinal data from six panel waves gathered in the Survey of Health, Ageing and Retirement in Europe, covering a time period of up to 14 years. The total sample size was N = 58,152 individuals aged 50 years or older. Frailty was based on a deficit accumulation frailty index and depressive symptoms were measured with the EURO-D scale. We used a latent curve model with structured residuals for statistical analysis.

RESULTS

The results did not demonstrate relevant cross-lagged effects of frailty and depression at the within-person level. However, within-person increases in frailty were accompanied by within-person increases in depression at the same point in time. At the between-person level, it showed that individuals with higher levels and steeper trajectories in frailty also tend to show higher levels and steeper trajectories in depression.

CONCLUSION

These findings question the notion that frailty and depression reciprocally influence each other over the course of time, but rather indicate that frailty and depression might be both affected by common causes, in both the short and the long term.