Bariatric surgery is an effective method in most of the obesity patients, however it is known that a substantial amount of the individuals fail to lose weight or regain a significant amount of the lost weight in a few years after the surgery .
There has been efforts to identify the possible factors for the failure to lose weight and sustain the weight loss in people with obesity. An important research area has been the problematic eating behaviors such as binge eating, and psychopathology, especially depression and impulsivity in obese patients. Although obesity is not classified as an eating disorder, various problematic eating behaviors including emotional eating, binge eating, and night eating syndrome have been documented in the obese individuals .
Considering the substantial portion of the bariatric patients had regained weight in the post-operative period, eating behaviors in bariatric candidates has been an area of interest in the last years, and bariatric surgery candidates have been found to have higher rates of eating problems compared to obese individuals seeking the traditional methods of weight loss .
Emotional eating is defined as the eating behavior emerging as a response to the negative emotions such as anxiety and irritability . Few studies have examined the prevalence of emotional eating in large general populations, on the other hand the prevalence of this behavior was found to be between 25% and 38% in some bariatric candidate groups indicating that emotional eating is very common in this group .
Some other studies yet reported similar emotional eating rates between obese individuals who seek traditional weight-loss programs and bariatric surgery candidates .
The prevalence rates of binge eating disorder in the individuals with obesity varied substantially due to different methods to evaluate this behavior, but generally reported to be between 10 to 30% .
Some studies have shown that the binge eating behavior is related to the severity of obesity and also psychopathology . Bariatric candidates were found to have more severe binge eating behaviors than obese individuals seeking non-surgical weight loss methods in many studies [3;9]. Patients with binge eating disorder were found to have other eating problems as well as depressive and anxiety disorders [10;11].
In addition to eating disorders, studies have revealed a relationship between obesity and other mental health problems. Depression is the most studied and most prevalent mental health problem in obese individuals . The exact mechanisms linking obesity and depression were not understood clearly, but there have been many hypotheses on the issue. Depressed individuals could develop obesity through dysregulated stress systems or through unhealthy lifestyles and maladaptive eating behaviors such as emotional eating, on the other hand obesity could lead to the development of depression through its negative effects on self-image and self-esteem. One meta-analysis reported that obesity increased the risk of depression while depression was also a predictor of the obesity .
Much of the work about the relationship of obesity and psychopathology has focused on discrete psychiatric diagnoses such as depression and bipolar disorder, however shared features across diagnoses such as impulsivity, and trait psychological characteristics such as emotion dysregulation and the use of pathological coping mechanisms, might be contributing to the maladaptive eating behaviors and obesity as a result .
Lack of impulse control over food may contribute to the weight gain and obesity; impulsivity and disinhibited behavior are known to be common for mood disorders, binge eating and substance use disorders; this common construct may explain the relationship between obesity and mental health problems like eating disorders and mood disorders. Whether these psychological constructs were playing a role in bariatric surgery outcome was also investigated in a few studies. One of these studies has worked on subtyping bariatric candidates based on regulative temperament, emotion dysregulation and disinhibited eating and investigated the effect of these subtypes on bariatric outcome . In this study, patients with pre-bariatric deficits in self and emotional control were found to have an increased risk for showing these deficits in post-operative period; however it was also found that neither pre- nor post-bariatric subtypes predicted the post-surgery weight loss. The conflicting evidence on the relationship of pre-operative psychopathology and post-surgery success has also been revealed in a meta-analysis .
Psychological stress has been suggested to be associated with disordered eating in many studies . But some of the researchers have proposed that instead of stress alone, the maladaptive coping strategies used to deal with stress are among the factors contributing to the development of maladaptive eating behaviors .
Coping mechanisms are defined as the behavioral and cognitive strategies used to manage stressing conditions and crises. Coping skills are not considered inherently adaptive or maladaptive, as it depends in which context they are used. However, problem-focused coping is generally associated with better adjustment whereas emotion-focused and avoidant coping are generally conceptualized as maladaptive styles and associated with psychopathology, including eating disorders .
Generally it was found there was a difference between people with or without an eating disorder regarding the coping strategies used: individuals with eating disorders demonstrate more emotion-focused and avoidant coping responses than the individuals without problematic eating behavior, actually disordered eating may be viewed as an avoidant coping strategy . Avoidant coping has also been proposed as a predictor of various eating disorders; the relationship between these maladaptive coping strategies and substance and eating disorders might be moderated by reward sensitivity, individuals using these strategies who also have higher reward sensitivity may be more likely to use substances or engage in maladaptive eating behavior to decrease their distress .
In sum, the pathological eating behaviors are common in bariatric candidates, and the pathological eating patterns could be related to some psychological constructs (trait characteristics) as well as discrete psychiatric diagnoses (state characteristics). Despite the rich literature on the relationship between eating disorders and those state and trait characteristics, the findings were mostly obtained from either adolescents from community or the individuals with obesity; the studies on bariatric candidates were very limited in this area. The aim of this study was to investigate the problematic eating patterns, and understand their relationship to some psychological constructs including impulsivity, stress coping mechanism and tolerance to emotional strain as well as psychiatric symptoms such as depression and anxiety among a group of bariatric surgery candidates. We hypothesized that depression and maladaptive coping behaviors, stress intolerance and impulsivity would be positively related to disordered eating behaviors in bariatric candidates.