Johannes Hebebrand – obesity and mental disorders

ESCAP 2015 Madrid State of the Art lecture

Potential mechanisms underlying the association between obesity and mental disorders and therapeutic implications

Johannes Hebebrand, Yvonne Mühlig, Özgyür Albayrak, Anke Hinney, Jochen Antel
University of Duisburg-Essen.

T3-01 – State of the Art Lecture, Tuesday June 23rd 2015.

Abstract

Mental disorders have been shown to be associated with obesity. The initial evidence stemmed from clinical studies that assessed the body mass index of patients with specific psychiatric disorders. Associations were also picked up by probing for mental disorders such as mood disorders or attention deficit/hyperactivity disorder (ADHD) in patients with obesity. These initial clinical associations led to population based studies, which were mostly able to confirm such associations. Furthermore, longitudinal studies have provided evidence to support bidirectionality: Probands with elevated depression scale scores gained on average more weight than non-depressed children, adolescents or adults. Vice versa, probands with obesity have been shown to have an elevated risk for the development of major depression. However, the data is not totally consistent. Gender differences have been observed; moderator effects such as socio-economic status also need to be considered. Furthermore, some studies also found evidence for a predictive value of underweight for the development of depression. Finally, large scaled adult studies have reported a protective effect of obesity for suicide.
Potential biological mechanisms can be classified according to 1) an overlapping genetic predisposition between obesity and the respective mental disorder, 2) inflammation, which has been shown to be associated with obesity and major depression, and 3) overlapping pathways involved in both mental function and body weight regulation. A lower socio-economic status is associated with both obesity and several mental disorders.
Obesity rates have increased substantially in many countries during the last decades of the 20th century leading to the term `obesity pandemic´. Increments were particularly pronounced for children and adolescents in both industrialized and emerging countries. For mental disorders there is some evidence to indicate that rates have also increased during this time period; the increase in help-seeking behavior has been documented unequivocally. Potentially environmental and societal factors that have entailed the obesity pandemic are also relevant for secular trends observed for some mental disorders. In particular, a reduction of physical activity is well documented in children and adolescents. This decreased physical activity level may predispose to the development of both overweight and specific mental disorders. Finally, nutrition has changed dramatically during this time period; the increase in consumption of processed foods is particularly relevant. Accordingly, dietary interventions have been proposed as a strategy for the treatment of depression.
Our presentation will focus on major depression and ADHD; we provide an overview of this research field and discuss potential therapeutic implications.

View or download the original presentation by Johannes Hebebrand (pdf, 91 slides).

View or download Johannes Hebebrand's presentation 'Bridging the gap between research and clinical practice – examples from anorexia nervosa' (pdf, 43 slides).