Relationship between psychological stress and metabolism in morbidly obese individuals

Despite evidence for a bidirectional relationship between obesity and stress-related mental disorders, the general relationship between psychological stress and metabolism is still controversial. Only few studies have addressed this relationship in morbidly obese individuals. The present study investigated the relationship between psychological distress, health-related quality of life (HRQL), eating behavior, negative emotions and body mass index (BMI), body composition and biomedical parameters of metabolism in an adult sample of 123 (94 females) morbidly obese individuals. No significant relationship was found between psychological distress and BMI, body composition or any of the parameters of metabolism; however, there was a strong and robust association between HRQL in the physical domain and BMI, body composition and several biomedical parameters of sugar and fat metabolism. The results also showed an interesting dissociation in the relationship between BMI and HRQL in the physical and psychology domains. Only little evidence was found for a relationship between eating behavior (e.g. restraint) or negative emotions (e.g. anger) and BMI, body composition and parameters of metabolism. There was, however, a significant gender difference in restraint eating. Other commonly reported gender differences in BMI, body composition, fat metabolism and liver values were also observed in this sample of morbidly obese individuals. Results from the present study highlight the relationship between HRQL in the physical domain and metabolism. Implications of these findings for weight loss treatment are discussed, emphasizing HRQL as an important treatment goal and the need for long-term psychological monitoring.