Gene-environment interplay in depressive symptoms: moderation by age, sex, and physical illness

Age and Sex Differences in the Genetic Architecture of Measures of Subjective Health: Relationships With Physical Health, Depressive Symptoms, and Episodic Memory

OBJECTIVES

Subjective health (SH) is not just an indicator of physical health, but also reflects active cognitive processing of information about one's own health and has been associated with emotional health measures, such as neuroticism and depression. Behavior genetic approaches investigate the genetic architecture of SH, that is, genetic and environmental influences on individual differences in SH and associations with potential components such as physical, cognitive, and emotional health. Previous twin analyses have been limited by sex, sample size, age range, and focus on single covariates.

METHODS

The current analysis used data from 24,173 adults ranging in age from 40 to 90 years from the international Interplay of Genes and Environment across Multiple Studies consortium to investigate the genetic architecture of 3 measures of SH: self-rated health, health compared to others, and impact of health on activities. Independent pathways model of SH included physical health, depressive symptoms, and episodic memory, with age, sex, and country included as covariates.

RESULTS

Most or all of the genetic variance for SH measures were shared with physical health, depressive symptoms, and episodic memory. Genetic architecture of SH differed across measures, age groups (40-65, 66-90), and sexes. Age comparisons indicated stronger correlations with all 3 covariates in older adults, often resulting from greater shared genetic variance.

DISCUSSION

The predictive value of SH has been amply demonstrated. The higher genetic contributions to associations between SH and its components in older adults support the increasing conceptualization with age of SH as an intuitive summation of one's vital reserve.

The Relationship Between Quality of Life and Depressive Symptoms Among Jordanian Community-Dwelling Older Adults

OBJECTIVE

The current study aimed to examine the relationship between depressive symptoms and quality of life among Jordanian community-dwelling older adults.

METHODS

A cross-sectional, descriptive correlational design was used. A convenience sample (N = 602) was selected to recruit the participants in the Amman governorate during the period from August to November 2021.

RESULTS

Findings demonstrated that the mean (SD) age of older adults was 67.5 (7.0) years and 51.5% of participants were females. Also, 54.1% of the participants experienced moderate to severe depressive symptoms with a total mean (SD) score was 8.57 on a scale of 0 to 15, while the mean (SD) for the quality of life scale was 12.12 (3.85) on a scale of 4 to 20. Significant differences existed in quality of life and depressive symptoms based on marital status (p < .001), educational level (p < .001), working status (p < .01), income (p < .001), and chronic disease (p < .01). Quality of life and its domains were negatively associated with depressive symptoms (B= - 0.596, p < .001). Also, marital status, working, educational level, income, and chronic disease were associated with depressive symptoms.

CONCLUSION

Strategies to improve quality of life should be promoted to minimize depressive symptoms among older adults and consider significant demographic factors.

Biological, Psychological, and Social Determinants of Depression: A Review of Recent Literature

Depression is one of the leading causes of disability, and, if left unmanaged, it can increase the risk for suicide. The evidence base on the determinants of depression is fragmented, which makes the interpretation of the results across studies difficult. The objective of this study is to conduct a thorough synthesis of the literature assessing the biological, psychological, and social determinants of depression in order to piece together the puzzle of the key factors that are related to this condition. Titles and abstracts published between 2017 and 2020 were identified in PubMed, as well as Medline, Scopus, and PsycInfo. Key words relating to biological, social, and psychological determinants as well as depression were applied to the databases, and the screening and data charting of the documents took place. We included 470 documents in this literature review. The findings showed that there are a plethora of risk and protective factors (relating to biological, psychological, and social determinants) that are related to depression; these determinants are interlinked and influence depression outcomes through a web of causation. In this paper, we describe and present the vast, fragmented, and complex literature related to this topic. This review may be used to guide practice, public health efforts, policy, and research related to mental health and, specifically, depression.

Air Pollution and the Dynamic Association Between Depressive Symptoms and Memory in Oldest-Old Women

BACKGROUND/OBJECTIVES

Exposure to air pollution may contribute to both increasing depressive symptoms and decreasing episodic memory in older adulthood, but few studies have examined this hypothesis in a longitudinal context. Accordingly, we examined the association between air pollution and changes in depressive symptoms (DS) and episodic memory (EM) and their interrelationship in oldest-old (aged 80 and older) women.

DESIGN

Prospective cohort data from the Women's Health Initiative Memory Study-Epidemiology of Cognitive Health Outcomes.

SETTING

Geographically diverse community-dwelling population.

PARTICIPANTS

A total of 1,583 dementia-free women aged 80 and older.

MEASUREMENTS

Women completed up to six annual memory assessments (latent composite of East Boston Memory Test and Telephone Interview for Cognitive Status) and the 15-item Geriatric Depression Scale (GDS-15). We estimated 3-year average exposures to regional particulate matter with aerodynamic diameter below 2.5 μm (PM_2.5 ) (interquartile range [IQR] = 3.35 μg/m³ ) and gaseous nitrogen dioxide (NO₂ ) (IQR = 9.55 ppb) at baseline and during a remote period 10 years earlier, using regionalized national universal kriging.

RESULTS

Latent change structural equation models examined whether residing in areas with higher pollutant levels was associated with annual changes in standardized EM and DS while adjusting for potential confounders. Remote NO₂ (β = .287 per IQR; P = .002) and PM_2.5 (β = .170 per IQR; P = .019) exposure was significantly associated with larger increases in standardized DS, although the magnitude of the difference, less than 1 point on the GDS-15, is of questionable clinical significance. Higher DS were associated with accelerated EM declines (β = -.372; P = .001), with a significant indirect effect of remote NO₂ and PM_2.5 exposure on EM declines mediated by DS. There were no other significant indirect exposure effects.

CONCLUSION

These findings in oldest-old women point to potential adverse effects of late-life exposure to air pollution on subsequent interplay between DS and EM, highlighting air pollution as an environmental health risk factor for older women.

RDoC and Psychopathology among Youth: Misplaced Assumptions and an Agenda for Future Research

Now over 10 years old, the Research Domain Criteria (RDoC) has gained impressive traction in the adult psychopathology literature, but enthusiasm among child and adolescent psychopathologists lags somewhat behind. We consider possible reasons why RDoC has not been embraced fully in the child and adolescent literatures. We emphasize common, interrelated, and sometimes outdated assumptions that impede scientific progress that RDoC could facilitate. Traditionally, child and adolescent psychopathologists have used behavioral syndromes as gold standards against which biological markers are validated, even though behavioral syndromes are often measured with less precision; sought to identify large main effects of single biological functions on single behavioral syndromes, thereby ignoring (even if implicitly) the overwhelming etiological complexity of psychopathology; expected 1:1 correspondencies between biological functions and behaviors, despite evidence that core biological systems subserving behavior are functionally interdependent (i.e., modulate one another); and failed to consider neurobiological mechanisms of homotypic and heterotypic comorbidity and continuity. Using examples from our work, we show how a developmental, RDoC-informed approach to externalizing behavior enriches our understanding of psychopathology. We also provide an agenda for future research, which includes calls to (1) adopt neural-systems-first approaches over disorder-first approaches when studying psychopathology, (2) eschew biological reductionism by integrating environmental risk mediators into our etiopathophysiological models, (3) integrate neural vulnerabilities into the empirical latent structure of psychopathology, and (4) replace null hypothesis significance testing with computational approaches that accommodate etiological complexity by evaluating functional dependencies among RDoC constructs, including positive valence systems (approach), negative valence systems (avoidance), and arousal/regulatory systems (self-regulation).

Associations Among Monoamine Neurotransmitter Pathways, Personality Traits, and Major Depressive Disorder

Major depressive disorder (MDD) is a complex psychiatric disease requiring multidisciplinary approaches to identify specific risk factors and establish more efficacious treatment strategies. Although the etiology and pathophysiology of MDD are not clear until these days, it is acknowledged that they are almost certainly multifactorial and comprehensive. Monoamine neurotransmitter system dysfunction and specific personality traits are independent risk factors for depression and suicide. These factors also demonstrate complex interactions that influence MDD pathogenesis and symptom expression. In this review, we assess these relationships with the aim of providing a reference for the development of precision medicine.

IGEMS: The Consortium on Interplay of Genes and Environment Across Multiple Studies - An Update

The Interplay of Genes and Environment across Multiple Studies (IGEMS) is a consortium of 18 twin studies from 5 different countries (Sweden, Denmark, Finland, United States, and Australia) established to explore the nature of gene-environment (GE) interplay in functioning across the adult lifespan. Fifteen of the studies are longitudinal, with follow-up as long as 59 years after baseline. The combined data from over 76,000 participants aged 14-103 at intake (including over 10,000 monozygotic and over 17,000 dizygotic twin pairs) support two primary research emphases: (1) investigation of models of GE interplay of early life adversity, and social factors at micro and macro environmental levels and with diverse outcomes, including mortality, physical functioning and psychological functioning; and (2) improved understanding of risk and protective factors for dementia by incorporating unmeasured and measured genetic factors with a wide range of exposures measured in young adulthood, midlife and later life.

Particulate Air Pollutants and Trajectories of Depressive Symptoms in Older Women

OBJECTIVES

Although several environmental factors contribute to the etiology of late-life depressive symptoms, the role of ambient air pollution has been understudied. Experimental data support the neurotoxicity of airborne particulate matter with aerodynamic diameter of ≤2.5 μm (PM_2.5), but it remains unclear whether long-term exposure is associated with late-life depressive symptoms. Our secondary aim was to explore whether the observed associations between exposure and depressive symptoms are explained by dementia risk.

DESIGN, SETTING, AND PARTICIPANTS

Prospective community-dwelling cohort study from the Women's Health Initiative Study of Cognitive Aging (1999-2010). Our analyses included 1,989 older women (baseline age 73.3 ± 3.75) with no prior depression or cognitive impairment.

MEASUREMENTS

Participants completed annual assessments of depressive symptoms (15-item Geriatric Depression Scale). Average ambient PM_2.5 exposure at the residential location was estimated by spatiotemporal modeling for the 3-years preceding each neuropsychological assessment. Participants underwent separate annual examinations for incident dementia defined by DSM-IV. Latent-class mixture models examined the association between PM_2.5 and identified trajectories of symptoms.

RESULTS

Six trajectories of depressive symptoms were identified. Across all women, PM_2.5 exposure was positively associated with depressive symptoms. The effect was especially strong in two clusters with sustained depressive symptoms (n = 625 sustained-mild [31%]; n = 125 sustained-moderate; [6%]). Among those with sustained-moderate symptoms, the estimated adverse effect of PM_2.5 exposure was greater than that of hypertension. Among women without dementia, associations were modestly attenuated.

CONCLUSION

Long-term exposure to ambient fine particles was associated with increased depressive symptoms among older women without prior depression or cognitive impairment.