Ian Wickramasekera developed the High Risk Model of Threat Perception (HRMTP), which provides us with a solid model to explain the effects of chronic stress, somatization, and eventual organic disease. The factors that are the greatest contributors to death and physical disease are chronic stress-related disorders, including eating disorders.
Many studies indicate that stressful events are among the prime causes of eating disorders. At Mirasol, we believe that stress precipitates, reinforces, and motivates much of disordered eating and that relieving that stress allows treatment to be more effective. Some of the sources of chronic stress that may precipitate and/or maintain an eating disorder are sexual, physical, or emotional abuse, difficulty in relationships with family and peers, personal illness that requires hospitalization, alcohol or drug abuse, difficulty in school, serious illness of parent, and leaving home for the first time. Some research has shown that the overall magnitude of life stress for bulimics is 2½ times greater than that for normal young women. Patients with more severe disordered eating behaviors reported an increased desire to binge and/or restrict in response to stressors, along with more global stress, lower self-esteem, and lower mastery (a person's ability to be in control of their environment). Thus, if life stressors remain present or reside in the patient's subconscious, the eating disorder is perpetuated.
Chronic stress may be expressed emotionally (anxiety, anger, depression), physiologically (physical decline and illness) and behaviorally resulting in impaired social functioning and maladaptive behaviors, and may result not only in the development of an eating disorder but in its maintenance as well.
The theory behind the HRMTP proposes that the interaction between a set of predisposers (such as high and low hypnotic ability, neuroticism, and catastrophizing), triggers (such as major life changes and microstressors), and buffers (such as a support system and coping skills) can predispose a person to developing chronic stress related disease. Another way Wickramasekera states this concept is that the HRMTP is a multidimensional model that "identifies three predisposing factors (hypnotic ability, catastrophizing, and negative affectivity) that amplify the probability that two triggering variables (major life change and minor hassles) will generate psychological or somatic symptoms unless the impact of the triggers and predisposers are buffered (by social support and coping skills)."
The HRMTP is a model that is made up of a variety of risk factors that, in combination, can amplify or reduce the symptoms of chronic stress. Many individuals adopt disordered eating behaviors as a way of coping with severe, often chronic, stress in their lives.
Hypnotizability in eating disordered populations is a risk factor that can be viewed as a personality trait as well as an ability. In eating disordered populations, bulimics are significantly more hypnotizable than anorexics; anorexics of the purging subtype generally are more hypnotizable than restricting anorexics. High hypnotizables are hypersensitive to psychological and physiological changes. They generally have superior sensory memory and have a superior ability to transfer information from sensory memory to short term memory.
Some researchers report that having the ability to experience dissociation may be a relevant factor in regards to the high hypnotizability found in bulimic patients. Clinicians have compared the acts of binge eating and purging to dissociative experiences. Other researchers found that in a group of 30 bulimics, 75% had experienced dissociation. Dissociation can also be present in binge eating disorder. Dissociation has not been found to be a feature of anorexia nervosa of the restricting type. Still other researchers report that hypnotizability and dissociation can be related to body image distortion which is common in both anorexia and bulimia nervosa. An individual who is highly hypnotizable can easily absorb or internalize the messages from society that promote a slim body shape as the ideal. This is the factor that is known as suggestibility. Internalization of the thin body ideal leads to body dissatisfaction. Both anorexics and bulimics have been found to have equivalent body image disturbances in regards to overestimation of body size. This population utilizes restrained eating as a strategy to meet society's ideal and also to reduce negative affect.
Many anorexics (as well as the morbidly obese) are of low hypnotic ability and as a result they frequently demonstrate a hyposensitivity to psychological and physiological changes, a tendency to deny psychological causation of behavior, and a propensity to remain in denial of the severity of their illness. The anorexic who is low in hypnotic ability is subject to stress disorders because he or she is relatively insensitive to or deficient in attention to relationships between psychological states and physiological states. They have a psychological insensitivity to changes in mood and feelings. They have a lack of proprioceptive or interoceptive awareness which means they lack the ability to discriminate between different feeling states in the body, such as being hungry and being full. Many anorexics are alexithymic, meaning they have no words for moods.
Neuroticism or negative affectivity (NA) is distinguished by the ability to remember unpleasant or aversive events that happened in the past. High NA individuals will feel increased discomfort at all times even without the presence of stress and will react more dramatically to difficult situations. They report more unpleasant feelings in times of stress and well as times of no stress. When individuals are high in negative affectivity, they tend to have more negative emotions, such as anxiety.
It is interesting to note that negative affectivity is a significant predictor of restrained eating in women. It is estimated that as many as 30% of American women may be restrained eaters. Restrained eaters depend on dieting rules rather than interoceptive awareness to dictate how they choose to eat. When individuals have a lack on interoceptive awareness, they lack the ability to tell when they are hungry or full. This population is more likely to experience weight cycling and has a greater likelihood for developing an eating disorder than unrestrained eaters.
Major hassles and minor stressors are both factors that can precipitate as well as promote the maintenance of an eating disorder. In 76% of cases, stressful life events or major hassles/minor stressors precede the onset of anorexia nervosa (AN) and bulimia nervosa (BN).
Coping is important as a way of mediating the stressors that can lead to psychological disorders, including eating disorders. Generally active coping strategies, such as taking action and problem solving, are associated with lower levels of stress, anxiety, and depression, and avoidant coping strategies are associated with increased psychological distress. Researchers found that anorexics and bulimics used more avoidance coping than did control subjects. Depression scores on the Beck Depression Inventory were related to avoidant coping so that the more depression patients exhibited, the more often they used avoidant coping methods.
Social support goes hand in hand with coping strategies and in some ways, it can be considered a type of coping strategy. If an individual is experiencing negative life stress, a way of coping with that stress could be reaching out to friends or family for emotional or financial support. One researcher has suggested that the presence of strong social support systems was a major factor in determining an individual's adjustment to stressful life events.
Of interest in which researchers found that "received social support does not have a direct or stress-buffering effect on psychological disorder." However, perceived social support can have a direct positive effect on stressful life events. They found that bulimics typically have impaired relationships with friends and family, reporting less perceived social support, more conflict in their relationships, and a reduced ability to be effective socially. More frequent bingeing and purging was associated with a higher level of social impairment. Eating disordered patients are more dissatisfied with their social support and feel more anxious and alienated from family and friends. Their lack of strong social support systems can be a factor in the maintenance of the disorder.