Depression and Obesity: Integrating the Role of Stress, Neuroendocrine Dysfunction and Inflammatory Pathways

Is Interleukin 17 (IL-17) Expression A Common Point in the Pathogenesis of Depression and Obesity?

(1) Background: Activated immune-inflammatory pathways play an important role in the pathogenesis of depression and pathological obesity. Obesity might promote production of cytokine interleukin 17, which plays a significant role in neuro-immune reactions. The study aimed at assessing the relationship between Body Mass Index (BMI) and IL-17 expression, taking into account the clinical psychiatric variables in patients with depression. (2) Methods: A total of 125 participants took part in the study (95 depressed patients, 30 healthy controls). Data concerning the course of depressive disorders and BMI were collected. The severity of depressive symptoms was assessed using the Hamilton Depression Rating Scale (HDRS). Reverse transcription polymerase chain reaction (RT-PCR) was used to assess IL-17 gene expression at the mRNA levels, while enzyme-linked immunosorbent assay (ELISA) was used to assess IL-17 expression at the protein level. (3) Results: Patients with more hospitalizations showed significantly higher IL-17 mRNA expression levels and higher BMI. However, no correlation between BMI and IL-17 expression was found in depressed patients. (4) Conclusions: Our study revealed that BMI does not affect IL-17 expression in patients with depression. However, further studies should be conducted to evaluate the effects of IL-17 inhibition on adipose tissue and vice versa.

The cafeteria diet: A standardized protocol and its effects on behavior

Obesity is a major health risk, with junk food consumption playing a central role in weight gain, because of its high palatability and high-energy nutrients. The Cafeteria (CAF) diet model for animal experiments consists of the same tasty but unhealthy food products that people eat (e.g. hot dogs and muffins), and considers variety, novelty and secondary food features, such as smell and texture. This model, therefore, mimics human eating patterns better than other models. In this paper, we systematically review studies that have used a CAF diet in behavioral experiments and propose a standardized CAF diet protocol. The proposed diet is ad libitum and voluntary; combines different textures, nutrients and tastes, including salty and sweet products; and it is rotated and varied. Our summary of the behavioral effects of CAF diet show that it alters meal patterns, reduces the hedonic value of other rewards, and tends to reduce stress and spatial memory. So far, no clear effects of CAF diet were found on locomotor activity, impulsivity, coping and social behavior.

Protective effect of the hydroalcoholic extract from Lampaya medicinalis Phil. (Verbenaceae) on palmitic acid- impaired insulin signaling in 3T3-L1 adipocytes

BACKGROUND

Obesity is strongly associated with insulin resistance (IR). IR at the molecular level may be defined as a diminished activation of insulin signaling-related molecules (IRS-1/Akt/AS160) as well as reduced glucose uptake. Subject with obesity have elevated plasma levels of saturated fatty acids, such as palmitic acid (PA), which triggers insulin signaling disruption in vivo and in vitro. Infusions of Lampaya medicinalis Phil. (Verbenaceae) are used in folk medicine of Northern Chile to counteract inflammatory diseases. Hydroethanolic extracts of lampaya (HEL) contain considerable amounts of flavonoids that may explain the biological activity of the plant. The aim of this study was to assess whether HEL exposure protects against PA-disrupted insulin signaling and glucose uptake in adipocytes.

METHODS

Cytotoxicity of a range of HEL concentrations (0.01-10 μg/mL) was evaluated in 3T3-L1 adipocytes. Cells were exposed or not to 0.1 μg/mL of HEL before adding 0.65 mM PA or vehicle and incubated with 100 nM insulin (or vehicle) for 15 min. Phosphorylation of Tyr-IRS-1, Ser-Akt, Thr-AS160 was evaluated by Western blot. Glucose uptake was assessed using the 2-NBDG analogue.

RESULTS

HEL was not cytotoxic at any concentration assessed. PA-induced reduction in insulin-stimulated phosphorylation of IRS-1, Akt and AS160 and glucose uptake were abolished by co-treatment with HEL.

CONCLUSION

These findings give new insights about the effect of HEL ameliorating PA- impaired IRS-1/Akt/AS160 pathway and glucose uptake in adipocytes. More studies should focus on lampaya, since might represent a preventive approach in individuals whose circulating PA levels contribute to IR.

The impact of sexual harassment on obesity in female adolescents: An update and perspective to control

BACKGROUND AND AIMS

Sexual victimization, happened during childhood and beyond, is known to be a substantial contributing factor for obesity development later in life. This work aims to bring about updated information on the relationship between sexual harassment and obesity.

METHODS

Based on an intensive scientific literature review in Google Scholar, Pubmed databases, the total of 106 studies (N = 141,199) were assessed including 52 studies on the connection between negative lifetime impacts and obesity, 11 studies on post-traumatic stress disorder (PTSD) symptoms with proposed biological mechanisms related to obesity, 15 studies on the relationship between major depressive disorder (MDD) symptoms and obesity, 11 studies on the body dismorphic disorder (BDD) and 17 studies on the binge eating disorder (BED) were also examined to evaluate the association of obesity and traumatic life experiences.

RESULTS

Although 40-70% of all cases related to obesity have been considered to be hereditary, many experts argue that deviations in the environment contribute to excessive food intake and depressed physical activity in numerous Western countries. Several studies have identified that childhood sexual abuse (CSA) may be nearly as common as obesity. However, just a few researchers have taken notice of the possible connection between these two.

CONCLUSIONS

By mentioning some possible obesity-related psychological disorders in response to CSA, we present updated information on the relationship between sexual harassment and obesity.

The relationship between multimorbidity and suicidal ideation: A meta-analysis

OBJECTIVE

Multimorbidity refers to the individual has two or more medical conditions, which include physical multimorbidity (two or more physical conditions), mental multimorbidity (two or more mental conditions) and physical and mental multimorbidity (one or more mental and one or more physical conditions). This study is to assess the relationship between multimorbidity and suicidal ideation (SI) by conducting a meta-analysis.

METHODS

Through using subject word and random word, Web of Science, Cochrane Library and PubMed were searched for related records up to March 2020. The Newcastle-Ottawa scale and the Agency for Healthcare Research and Quality were used to evaluate the quality of included studies. Subgroup and sensitivity analysis were performed. The publication bias was evaluated by the funnel plots, Begg's test and Egger's test.

RESULTS

A total of 19 studies were included for analysis. The pooled odd ratio (OR) for the association between multimorbidity and SI was 2.90 (95%CI 2.29-3.67, P < .001). Subgroup analysis based on nature of study, category of multimorbidity, country, whether adjusted the covariates, and quality ratings was performed. The result of sensitivity analysis indicated that no individual studies had a substantial impact on the pooled OR. There was no publication bias in the studies.

CONCLUSIONS

Multimorbidity is one important factor in increased risk of SI. It is critical to assessing SI among patients with multimorbidity in primary care and specialty medical practices, particularly among physical and mental multimorbidity patients who may have higher risk of SI.

Study of decreased serum levels of retinol binding protein 4 in major depressive disorder

BACKGROUND

Studies in western populations find that obesity and depression are positively correlated. Adipokines secreted by adipose tissue may serve as the crosstalk link between peripheral tissue and central nervous system, which mediates the relationship between obesity and depression.

OBJECTIVE

This study aimed to investigate serum retinol-binding protein 4 (RBP4) concentration in patients with major depressive depression (MDD) and clarify its possible association with depression.

METHODS

Major depressive disorder patients (n = 237), healthy controls (n = 48) were collected from June 2017 to October 2019. The measurement of RBP4 levels was performed by Advia 2400 automatic biochemistry analyzer. Depressive symptoms of patients were assessed using the 24-item Hamilton Depression Scale (HAMD-24).

RESULTS

(1) Serum RBP4 levels of MDD patients were significantly lower than that of the control group [(34.25 ± 8.82) mg/L vs (37.56 ± 8.83) mg/L] (P < 0.05) which was independent from obesity; (2) The level of RBP4 [(31.13 ± 9.16) mg/L] in suicide attempt (SA) group was significantly lower than that in the control group and non-suicide attempt (non-SA) group [(35.55 ± 8.37)mg/L](P < 0.05); (3) There was no significant correlation between serum RBP4 concentration and HAMD-24 score (P > 0.05); serum RBP4 concentrations were positively associated with age, age of onset and duration of disease (r = 0.325, 0.298, 0.135; P < 0.001, P < 0.001, P = 0.038) in depressive patients. (4) The level of serum RBP4 was positively correlated with TC, TG, and LDL-C (r = 0.350, 0.207, 0.268; P < 0.001, P = 0.001, P < 0.001), but not with other blood lipid indexes. ROC curve of RBP4 for MDD revealed an area under the curve of 0.603 and a sensitivity of 81.3%, specificity of 80%.

CONCLUSION

The level of RBP4 in patients with MDD was lower than that in the normal control group, which might be related to the prognosis of patients with depression.

Obesity and Depression: Its Prevalence and Influence as a Prognostic Factor: A Systematic Review

OBJECTIVE

Depression and obesity are two conditions with great impact over global health. This is mainly due to their high prevalence and the morbidity and mortality associated to both. The main aim of the present systematic review is to study the association between obesity and depression and the prognostic implications derived from it.

METHODS

A literature review was performed in the PUBMED database. 18 articles were found (9 cross-sectional studies, 6 longitudinal studies and 3 clinical trials), which were reviewed by critical reading after which a summary of the main conclusions was written.

RESULTS

These selected articles confirmed that there is indeed a link between depression and obesity, although there are doubts as to the significance of this relationship. Depression is a risk factor for obesity, especially atypical depression and in African-American adolescent males. Obesity is a risk factor for depression, especially in women and for recurrent depressive disorder. The comorbidity between obesity and depression is a risk factor for a bad prognosis illness.

CONCLUSION

The relationship between both disorders has been analysed in scientific literature, obtaining significant associations but also contradictory results. The most current data demonstrates that there is a relationship between both entities, although there is no unanimity when it comes to establishing the meaning of this association.

Depression and Obesity: Analysis of Common Biomarkers

Depression and obesity are very common pathologies. Both cause significant problems of both morbidity and mortality and have decisive impacts not only on the health and well-being of patients, but also on socioeconomic and health expenditure aspects. Many epidemiological studies, clinical studies and meta-analyses support the association between mood disorders and obesity in relationships to different conditions such as the severity of depression, the severity of obesity, gender, socioeconomic status, genetic susceptibility, environmental influences and adverse experiences of childhood. Currently, both depression and obesity are considered pathologies with a high-inflammatory impact; it is believed that several overlapping factors, such as the activation of the cortico-adrenal axis, the exaggerated and prolonged response of the innate immune system and proinflammatory cytokines to stress factors and pathogens-as well as alterations of the intestinal microbiota which promote intestinal permeability-can favor the expression of an increasingly proinflammatory phenotype that can be considered a key and common phenomenon between these two widespread pathologies. The purpose of this literature review is to evaluate the common and interacting mechanisms between depression and obesity.

Less Animal-Based Food, Better Weight Status: Associations of the Restriction of Animal-Based Product Intake with Body-Mass-Index, Depressive Symptoms and Personality in the General Population

Restricting animal-based products from diet may exert beneficial effects on weight status; however, less is known about such a diet and emotional health. Moreover, personality traits, for example high neuroticism, may contribute to restrictive eating habits and potentially confound diet-health associations. We aim to systematically assess if restrictive dietary intake of animal-based products relates to lower weight and higher depressive symptoms, and if differences in personality traits play a significant role. Cross-sectional data from the baseline LIFE-Adult study were collected from 2011–2014 in Leipzig, Germany (n = 8943). Main outcomes of interest were dietary frequency of animal-derived products in the last year measured using a Food Frequency Questionnaire (FFQ), body-mass-index (BMI) (kg/m²), and the Center of Epidemiological Studies Depression Scale (CES-D). Personality traits were assessed in a subsample of n = 7906 using the Five Factor Inventory (NEO-FFI). Higher restriction of animal-based product intake was associated with a lower BMI, but not with depression scores. Personality, i.e., lower extraversion, was related to higher frequency of animal product intake. Moreover, personality traits were significantly associated with depressive symptoms, i.e., higher neuroticism, lower extraversion, lower agreeableness, lower conscientiousness, and with higher BMI. These findings encourage future longitudinal studies to test the efficacy of restricting animal-based products as a preventive and therapeutic strategy for overweight and obesity.

Hydroethanolic Extract of Lampaya Medicinalis Phil. (Verbenaceae) Decreases Proinflammatory Marker Expression in Palmitic Acid-exposed Macrophages

BACKGROUND

Obesity is a major health problem associated with increased comorbidities, which are partially triggered by inflammation. Proinflammatory macrophage infiltration in adipose tissue of individuals with obesity increases chronic inflammation. Obesity is associated with elevated plasma levels of saturated fatty acids, such as palmitic acid (PA), which promotes inflammation in vivo and in vitro. Infusions of Lampaya medicinalis Phil. (Verbenaceae) are used in the folk medicine of Northern Chile to counteract inflammation of rheumatic diseases. Hydroethanolic extract of lampaya (HEL) contains spectrophotometrically defined compounds that may contribute to the observed effect on inflammation.

METHODS

We evaluated the phytochemical composition of HEL by high-performance liquid chromatography coupled to diode array detection (HPLC-DAD) and liquid chromatography-electrospray ionization- tandem mass spectrometry (LC-ESI-MS/MS). We assessed whether the exposure to HEL affects PA-induced expression of proinflammatory factors in THP-1 macrophages.

RESULTS

HPLC-DAD and LC-ESI-MS/MS analyses showed the presence of considerable amounts of flavonoids in HEL. The PA-induced phosphorylation of the inflammatory pathway mediators IKK and NF-κB, as well as the elevated expression and secretion of proinflammatory cytokines (IL-6, TNF-α), were reduced in cells pre-exposed to HEL.

CONCLUSION

These findings give new insights about the effect of HEL reducing IKK/NF-κB proinflammatory pathway, likely explained by the number of flavonoids contained in the extract. More studies would be needed to define the possible role of Lampaya as a preventive approach in subjects with obesity whose circulating PA might contribute to chronic inflammation.

The effects of stress on cardiovascular disease and Alzheimer's disease: Physical exercise as a counteract measure

AD is a complicated multi-systemic neurological disorder that involves different biological pathways. Several risk factors have been identified, including chronic stress. Chronic stress produces an alteration in the activity of the hypothalamic pituitary adrenal (HPA) system, and the autonomic nervous system (ANS), which over time increase the risk of AD and also the incidence of cardiovascular disease (CVD) and risk factors, such as hypertension, obesity and type 2 diabetes, associated with cognitive impairment and AD. Considering the multi-factorial etiology of AD, understanding the complex interrelationships between different risk factors is of potential interest for designing adequate strategies for preventing, delaying the onset or slowing down the progression of this devastating disease. Thus, in this review we will explore the general mechanisms and evidence linking stress, cardiovascular disease and AD, and discuss the potential benefits of physical activity for AD by counteracting the negative effects of chronic stress, CVD and risk factors.

Reported and Recorded Sleepiness in Obesity and Depression

BACKGROUND

Obesity and depression are both associated with changes in sleep/wake regulation, with potential implications for individualized treatment especially in comorbid individuals suffering from both. However, the associations between obesity, depression, and subjective, questionnaire-based and objective, EEG-based measurements of sleepiness used to assess disturbed sleep/wake regulation in clinical practice are not well known.

OBJECTIVES

The study investigates associations between sleep/wake regulation measures based on self-reported subjective questionnaires and EEG-derived measurements of sleep/wake regulation patterns with depression and obesity and how/whether depression and/or obesity affect associations between such self-reported subjective questionnaires and EEG-derived measurements.

METHODS

Healthy controls (HC, N_HC = 66), normal-weighted depressed (DEP, N_DEP = 16), non-depressed obese (OB, N_OB = 68), and obese depressed patients (OBDEP, N_OBDEP = 43) were included from the OBDEP (Obesity and Depression, University Leipzig, Germany) study. All subjects completed standardized questionnaires related to daytime sleepiness (ESS), sleep quality and sleep duration once as well as questionnaires related to situational sleepiness (KSS, SSS, VAS) before and after a 20 min resting state EEG in eyes-closed condition. EEG-based measurements of objective sleepiness were extracted by the VIGALL algorithm. Associations of subjective sleepiness with objective sleepiness and moderating effects of obesity, depression, and additional confounders were investigated by correlation analyses and regression analyses.

RESULTS

Depressed and non-depressed subgroups differed significantly in most subjective sleepiness measures, while obese and non-obese subgroups only differed significantly in few. Objective sleepiness measures did not differ significantly between the subgroups. Moderating effects of obesity and/or depression on the associations between subjective and objective measures of sleepiness were rarely significant, but associations between subjective and objective measures of sleepiness in the depressed subgroup were systematically weaker when patients comorbidly suffered from obesity than when they did not.

CONCLUSION

This study provides some evidence that both depression and obesity can affect the association between objective and subjective sleepiness. If confirmed, this insight may have implications for individualized diagnosis and treatment approaches in comorbid depression and obesity.

The moderating role of race/ethnicity and nativity in the relationship between perceived discrimination and overweight and obesity: results from the National Epidemiologic Survey on Alcohol and Related Conditions

BACKGROUND

The overweight/obesity epidemic is a public health issue in the United States (US), that disproportionately affect certain racial/ethnic minority groups. Perceived discrimination has been implicated as a health risk factor. However, research on race/ethnicity, perceived discrimination, and obesity has been mixed. Researchers suggest that perceptions of discrimination may be dependent upon nativity status. This study evaluated the role that nativity status and race/ethnicity play in the relationship between perceived discrimination and overweight/obesity.

METHODS

We used Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (2004-2005) [N = 33,319]). Multinomial logistic regression assessed a three-way interaction (perceived discrimination × race/ethnicity × nativity) on overweight and obesity, adjusting for sociodemographic factors and health-related behaviors.

RESULTS

The three-way interaction was significant for overweight [F (17, 49) = 3.35; p < 0.001] and obesity [F (17, 49) = 5.05; p < 0.001]. Among US-born individuals, US-born non-Hispanic Blacks had a decreased risk of being obese compared to US-born non-Hispanic Whites at mean levels of perceived discrimination [aRRR = 0.71; 95% CI (0.51-0.98); p = 0.04). Among foreign-born individuals, foreign-born South Americans had an increased risk of being overweight at mean levels of perceived discrimination compared to foreign-born non-Hispanic Whites [aRRR = 8.07; 95% CI (1.68-38.77); p = 0.01], whereas foreign-born Dominicans had a decreased risk of being obese compared to foreign-born non-Hispanic Whites [aRRR = 0.05; 95% CI (0.01-0.20); p < 0.001].

CONCLUSION

Perceived racial discrimination is a risk factor for overweight/obesity for certain groups. Race/ethnicity and nativity may play important roles in the relationship between perceived discrimination and overweight/obesity. Future research is needed to identify the behavioral and psychological pathways that link perceived discrimination and overweight/obesity.

Psychosocial Stress and Overweight and Obesity: Findings From the Chicago Community Adult Health Study

BACKGROUND

Psychosocial stress has been implicated as a risk factor for overweight and obesity. However, research on psychosocial stressors and overweight and obesity has typically focused on single stressors in isolation, which may overestimate the impact of a specific stressor and fail to describe the role of cumulative stress on overweight and obesity risk.

PURPOSE

This study explores the association between overweight/obesity and cumulative exposure to a wide range of psychosocial stressors, among a multiracial/ethnic sample of adults.

METHODS

Using secondary data from the Chicago Community Adult Health Study (n = 2,983), we conducted multinomial logistic regression analyses to quantify associations between eight psychosocial stressors, individually and in combination, and measured overweight and obesity, adjusted for sociodemographic factors, alcohol use and smoking.

RESULTS

In separated covariate-adjusted models, childhood adversities (odds ratio [OR] = 1.16; confidence interval [CI] = [1.03, 1.30]), acute life events (OR = 1.18; CI = [1.04, 1.34]), financial strain (OR = 1.30; CI = [1.15, 1.47]), and relationship stressors (OR = 1.18; CI = [1.04, 1.35]) were associated with increased odds of obesity. In a model adjusted for all stressors simultaneously, financial strain was the only stressor independently associated with overweight (OR = 1.17; CI = [1.00, 1.36]) and obesity (OR = 1.21; CI = [1.05, 1.39]). Participants with stress exposure in the highest quintile across 2, 3, or ≥4 (compared to no) types of stressors had significantly higher odds of obesity.

CONCLUSIONS

Multiple types of stressors may be risk factors for obesity, and cumulative exposure to these stressors may increase the odds of obesity. Reducing exposure to stressors at the population level may have the potential to contribute to reducing the burden of obesity.

Physical exercise and body mass index as correlates of major depressive disorder in community-dwelling adults: Results from the PISMA-ep study

BACKGROUND

Major Depressive Disorder (MDD) is one of the most prevalent and disabling mental disorders. Sedentarism and obesity are recognized risk factors for MDD. Physical exercise has shown beneficial effects on mental health and there is an increasing awareness of its potential as a therapeutic and preventive tool for depression. No epidemiological studies have explored the role of physical activity and obesity as potential correlates of MDD in the Spanish population. The aim of this study was to explore whether MDD was associated with two strongly linked variables: physical exercise and body mass index.

METHODS

The PISMA-ep is a cross-sectional community-based study carried out in Andalusia, southern Spain. Main outcome was current prevalence of MDD, measured through face-to-face interviews using the Mini-International Neuropsychiatric Interview (MINI). Independent variables explored were physical exercise and its intensity, Body Mass Index (BMI), BMI categories (underweight, normal weight, overweight and obesity), hip and waist circumferences, general health status measured with the SF12 questionnaire, and sociodemographic factors.

RESULTS

Physical exercise was inversely associated with MDD, acting as a protective factor. Higher intensity of exercise strengthened this association. Four variables were independently associated with MDD in the multivariate association model: female sex, physical exercise, general health status and BMI.

CONCLUSION

MDD was associated with poorer health status, higher BMI and reduced physical activity. Physical exercise should be considered as a potential intervention for the treatment and prevention of MDD in clinical and public health settings.

Genetic variation in CADM2 as a link between psychological traits and obesity

CADM2 has been associated with a range of behavioural and metabolic traits, including physical activity, risk-taking, educational attainment, alcohol and cannabis use and obesity. Here, we set out to determine whether CADM2 contributes to mechanisms shared between mental and physical health disorders. We assessed genetic variants in the CADM2 locus for association with phenotypes in the UK Biobank, IMPROVE, PROCARDIS and SCARFSHEEP studies, before performing meta-analyses. A wide range of metabolic phenotypes were meta-analysed. Psychological phenotypes analysed in UK Biobank only were major depressive disorder, generalised anxiety disorder, bipolar disorder, neuroticism, mood instability and risk-taking behaviour. In UK Biobank, four, 88 and 172 genetic variants were significantly (p < 1 × 10⁻⁵) associated with neuroticism, mood instability and risk-taking respectively. In meta-analyses of 4 cohorts, we identified 362, 63 and 11 genetic variants significantly (p < 1 × 10⁻⁵) associated with BMI, SBP and CRP respectively. Genetic effects on BMI, CRP and risk-taking were all positively correlated, and were consistently inversely correlated with genetic effects on SBP, mood instability and neuroticism. Conditional analyses suggested an overlap in the signals for physical and psychological traits. Many significant variants had genotype-specific effects on CADM2 expression levels in adult brain and adipose tissues. CADM2 variants influence a wide range of both psychological and metabolic traits, suggesting common biological mechanisms across phenotypes via regulation of CADM2 expression levels in adipose tissue. Functional studies of CADM2 are required to fully understand mechanisms connecting mental and physical health conditions.

Race and income moderate the association between depressive symptoms and obesity

Complex interrelationships between race, sex, obesity and depression have been well-documented. Because of differences in associations between socioeconomic status (SES) and health by race, determining the role of SES may help to further explicate these relationships. The aim of this study was to determine how race and income interact with obesity on depression. Combining data from the 2007-2014 National Health and Nutrition Examination Survey, depressive symptoms was measured with the Patient Health Questionnaire-9 and obesity was assessed as body mass index ≥30 kg/m2. Three-way interactions between race, income and obesity on depressive symptoms were determined using ordered regression models. Significant interactions between race, middle income and obesity (OR = 0.66, 95% CI = 0.22-1.96) suggested that, among white women, obesity is positively associated with depressive symptoms across income levels, while obesity was not associated with depression for African American women at any income level. Obesity was only associated with depressive symptoms among middle-income white men (OR = 1.44, 95% CI = 1.02-2.03) and among high-income African American men (OR = 4.65, 95% CI = 1.48-14.59). The associations between obesity and depressive symptoms vary greatly by race and income. Findings from this study underscore the importance of addressing obesity and depression among higher income African American men.

Depression and obesity, data from a national administrative database study: Geographic evidence for an epidemiological overlap

Background

Depression and obesity are two major conditions with both psychological and somatic burdens. Some data suggest strong connections between depression and obesity and more particularly associated prevalence of both disorders. However, little is known about the geographical distribution of these two diseases. This study aimed to determine if there is spatial overlap between obesity and depression using data from the entire French territory.

Methods

Data for 5,627 geographic codes for metropolitan France were collected from the two national hospital databases (PMSI-MCO and RIM-P) for the year 2016. We identified people who were depressed, obese or both registered in the two public medico-administrative databases, and we assessed their location. In addition, a multivariable analysis was performed in order to determine geographic interactions between obesity and depression after controlling for age, sex, environmental and socio-economic factors (social/material deprivation, urbanicity/rurality).

Results

1,045,682 people aged 18 years and older were identified. The mapping analysis showed several cold and hot regional clusters of coinciding obesity and depression. The multivariable analysis demonstrated significant geographic interactions, with an increasing probability of finding a high prevalence of obesity in regions with major depression (OR 1.29 95% CI 1.13–1.49, p = 0.0002) and an increased probability of finding a high prevalence of depression in regions with a high ration of obesity (OR 1.32, 95% CI 1.15–1.52, p<0.0001).

Conclusion

Our study confirms the significant bidirectional relationships between obesity and depression at a group level. French geographic patterns reveal a partial overlap between obesity and depression, suggesting these two diseases can be included in a common approach. Further studies should be done to increase the understanding of this complex comorbidity.