BRAIN MECHANISMS UNDERLYING NEGATIVE AFFECT INDUCED SOMATIC SYMPTOM REPORTING IN FUNCTIONAL SOMATIC SYNDROME PATIENTS

Abstract

Background. Obesity may increase the risk of depression, but symptom-specific associations that could potentially inform more targeted treatments remain uncertain. We explored the cross-sectional and longitudinal associations between excess body weight and an array of depression-related symptoms. Method. This random-effects pooled analysis included 57,532 individuals from 15 population-based cohorts aged >18 years. Height and weight were measured at baseline and body mass index (BMI) was computed. Using validated self-report measures, 24 symptoms of depression were assessed once in 15 cross-sectional, and twice in 7 prospective cohort studies (mean follow-up 3.2 years). Results. At baseline, 38.3% of participants were overweight (BMI between 25 and 29.9), 20.9% class I obese (BMI between 30 and 34.9), and 13.0% class II-III obese (BMI>35). A total of 12.3% were classified as depressed. The proportion of depressive symptoms ranged between 1·1% (suicidal ideation) and 21.4% (sleep problems). After adjustment for demographic and illness-related factors, obesity class I was associated cross-sectionally with 1.11-fold (95% confidence interval 1.01-1.22) and obesity class II-III with 1.31-fold (1.16-1.49) higher odds of depression. In symptom-specific analyses, equally strong or stronger associations were observed for five distinct symptoms: everything was an effort, lack of energy, little interest in doing things, felt bad about myself, and felt depressed. The odds of having three or more versus none, one, or two of the identified symptoms were 1.26 (1.04-1.53) for obesity class I and 1.64 (1.35-2.00) for obesity class II-III. Symptom-specific associations were confirmed in longitudinal analyses; among individuals with depression; in age-stratified analyses; and were stronger in women compared with men. In contrast, we found robust evidence against an association between obesity and four symptoms: felt fearful, hopeless, life had been a failure, and talked less than usual. Conclusions. Individuals with obesity, particularly women, are prone to a distinct set of depression-related symptoms not well characterized by existing depression subtypes, such as atypical or melancholic depression. Awareness of this specific obesity-related symptom profile may inform future research and the design of personalized treatments for depression and obesity. Background: Characterized by persistent abdominal pain and altered bowel habits, irritable bowel syndrome (IBS) is a chronic visceral pain disorder with prevalence rates of 8-12% of the population. The aim of this study was to explore brain changes underpinning IBS symptom improvement in response to mindfulness-based treatment. Therefore, single arm interventional design was employed to determine the effects of mindfulness-based stress reduction (MBSR), on brain resting state functional connectivity (RSFC) in IBS.