Pathways linking physical and mental health: The role of brain structure and lifestyle factors
Poster No:
517
Submission Type:
Abstract Submission
Authors:
Ye Tian1, Andrew Zalesky2
Institutions:
1University of Melbourne, Carlton South, Victoria, 2The University of Melbourne, Melbourne, Victoria
First Author:
Co-Author:
Introduction:
Depression and anxiety are common mental health problems. They are not only highly comorbid with each other; the prevalence of depression and anxiety is also high in individuals with a chronic physical health condition. Multiple putative biological and psychosocial pathways have been proposed, attempting to explain the link between physical and mental health problems. However, the brain is rarely considered in these models, albeit that depression and anxiety are commonly associated with alterations in brain structure and function. We sought to understand mechanisms of neurobiology in the concurrent manifestation of physical and mental health.
Methods:
Multimodal brain imaging (structural and diffusion-weighted MRI), physiological, blood- and urine-derived markers from 18, 128 individuals (7,455 males) participating in the UK Biobank were used in this study. Physical health was assessed for each body organ (cardiovascular, pulmonary, musculoskeletal, immune, renal, hepatic and metabolic) using organ-specific phenotypes (40-70 years, mean 53.7 ± 7.3). Brain imaging was acquired at 4-14 years follow-up (45-83 years, mean 62.7 ± 7.5). Normative models were used to assess the extent to which each individual's organ health and function deviated from an age- and sex-specific normative references ranges (mean and centiles). Structural equation modeling was used to test the significance of pathways from physical health to mental health via structural alterations in brain gray and white matter. Lifestyles factors that can influence symptoms of depression, anxiety and neuroticism via influencing organ health and brain structure were identified.
·Overview of study design
Results:
We found multiple significant pathways through which poor organ health may lead to poor brain health, which in turns lead to poor mental health. In general, the brain showed strong mediating effect on organs that had strong direct effect on mental health outcome, which is mostly exemplified by the musculoskeletal and immune systems. However, specific pathways were observed linking specific organ systems and mental health, exemplified by pulmonary and cardiovascular systems. Specifically, we found that GM showed significant mediating effect on pulmonary-depression and pulmonary-neuroticism but not pulmonary-anxiety associations, whereas WM showed significant mediating effect on associations of cardiovascular-anxiety and cardiovascular-neuroticism, but not cardiovascular-depression.
We found that lifestyle exposure had impact on depression and neuroticism via influencing organ health and brain structure. However, the mediation effects were not significant for anxiety. Significant pathways were identified for all 7 organ systems for depression via GM, but not via WM. In contrast, significant pathways leading to neuroticism were mainly through WM and were evident for 5 organ systems including immune, musculoskeletal, metabolic, hepatic and pulmonary system. Notably, we found that while some lifestyle factors, including physical activity, sedentary behavior, diet, sleep quality, degree of education and socioeconomic inequality, influenced mental health via influencing multiple body and brain systems, some other lifestyle factors, particularly of smoking and alcohol intake, had more specific path affecting mental health through metabolic and pulmonary system, and musculoskeletal and hepatic system, respectively.
We found that lifestyle exposure had impact on depression and neuroticism via influencing organ health and brain structure. However, the mediation effects were not significant for anxiety. Significant pathways were identified for all 7 organ systems for depression via GM, but not via WM. In contrast, significant pathways leading to neuroticism were mainly through WM and were evident for 5 organ systems including immune, musculoskeletal, metabolic, hepatic and pulmonary system. Notably, we found that while some lifestyle factors, including physical activity, sedentary behavior, diet, sleep quality, degree of education and socioeconomic inequality, influenced mental health via influencing multiple body and brain systems, some other lifestyle factors, particularly of smoking and alcohol intake, had more specific path affecting mental health through metabolic and pulmonary system, and musculoskeletal and hepatic system, respectively.
Conclusions:
In conclusion, our work provides an integrated model linking physical health, neurobiology and mental health outcome. Our findings suggest a crucial role of the brain in mediating the relationship between physical and mental health, which is an important step toward bridging the mind-body dualism. The modifiable lifestyle factors identified from this study can potentially inform the development of targeted interventions to improve both physical and mental health synergistically.
Disorders of the Nervous System:
Psychiatric (eg. Depression, Anxiety, Schizophrenia) 1
Modeling and Analysis Methods:
Multivariate Approaches 2
Keywords:
Anxiety
MRI
Other - Depression; Normative modelling; Brain-Body
1|2Indicates the priority used for review
Provide references using author date format
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