This unhealthy behaviour is the cause of several negative physical problems. For instance, bulimic people have a constant feeling of weakness and tiredness due to problems in their muscles and bones. Moreover, possible complications of bulimia include dental problems, caused by the stomach acid, dry skin and hair, swollen glands, fits and muscle spasm. Heart, kidney or bowel problems, including permanent constipation, along with bone problems such as osteoporosis, are other effects of bulimia. Considering these health risks, why would people decide to adopt such a destructive behaviour? Although on the surface, it appears that the main concern of bulimic people is their physical aspect, this worry is simply a symptom, a consequence, of more profound and serious issues. Several can be the causes behind the development of bulimia nervosa. It can be triggered by a genetic component, the social context, the personality of the person or a traumatic event (“Bulimia”, 2017). By analysing the family history of the patients, it seems that quite often members of the family have experienced episodes of depression, alcohol/drug addiction or eating disorders (the genetic component is between 30% -80%). The social context does seem to play a role as well, for instance, some of them might pressure people to be extremely slim (e.g. ballet dancers or models). Moreover, BN could also be caused by several critiques that have been made on the patient regarding her/his eating habits, body shape and weight. When it comes to personality traits instead, bulimic people usually have similar characteristics. For instance, they suffer from anxiety, they have a low-self-esteem, an obsessive personality, they are perfectionists, and want to be in control of every external situation. Lastly, people might engage in this destructive behaviour as a consequence of a traumatic event occurred to them in the past. For instance, some people who have been sexually abused developed bulimia nervosa.
Throughout the years, doctors, psychotherapists and psychiatrists have worked in order to create efficient methods to treat this disorder. Fortunately, people can recover from bulimia nervosa and its main treatments are interpersonal therapy (IPT), family therapy, medication, and cognitive behavioural therapy (CBT). Interpersonal therapy does not focus on reducing the bulimic symptoms, instead, it aims at identifying and work on the interpersonal problem(s) of the patients that appears to be related to the development of their eating disorder. This therapy is helpful for people who do not want clear behavioural directives, but they are looking for a treatment with some structure, focus and containment (Apple, 1999). IPT usually results in changes across all areas of symptoms, the only issue is that, compared to CBT, it takes longer to achieve its effects (Fairburn, 1993). The family therapy treatment (20 weeks long) is often offered to children and adolescents. In this intervention, doctors meet the family members along with the patient and provide them with practical strategies to overcome this eating disorder. There has been a number of positive response to this type of therapy, but mainly in adolescents with a relatively short history of bulimia nervosa (Stewart, Voulgari, Eisler, Hunt & Simic, 2015). Since people with BN also tend to have anxiety, depression, social phobia or obsessive-compulsive disorder, the therapists might decide to provide to the patients, in combination with a psychotherapy treatment, antidepressants such as fluoxetine (Prozac). This essay, however, will focus on the last treatment method previously listed: cognitive behavioural therapy.
CBT is one of the most widely recognised treatments used in several clinical domains. In the case of bulimia nervosa, CBT is chosen when patient age does not mandate family therapy and when their symptoms are moderate to severe. Despite CBT recognises that this disorder is also caused by biological factions, its model bases the intervention on the assumption that BN develops due to cognitive disturbances and behavioural disturbances. The former ones cause people to be overly concern about their eating habits and the shape/weight of their bodies while the latter ones affect the persons’ eating controlling behaviour. As bulimic people internalise these beliefs they develop a dysfunctional schema. This cognitive schema is express through the patients’ external behaviour, as they become extremely focused on their body and they aim to obtain unrealistic levels of thinness and control (Wilson, Fairburn, Agras, Walsh & Kraemer, 2002). Studies have shown that CBT is the intervention with the most evidence-based positive outcomes (e.g., Craske, 2010). This therapy is well-structured, has a time-limit, it is focused on the present, and it is directive which means that the clinician actively offers advice and information to the patient instead of just basing the therapy sessions only on the information supplied by the client. These stylistic features seem to be perfect for bulimic people as they usually experience lack of control in terms of their eating and in other areas of their life, therefore CBT helps them to find a safe, containing structure where they can work on changing their maladaptive behaviours.
Cognitive behaviour therapy program for Bulimia Nervosa involves approximately 20 sessions (one session per week) (Fairburn, Marcus, & Wilson, 1993). These sessions are divided into three phases. In the first one, bulimic patients learn the negative physical and psychological problems caused by binge eating, purging and extreme dieting. Along with this psychoeducation, the therapists teach patients to establish a regular pattern of eating and to learn how and when to monitor their own weight. In the second phase, patients learn how to adjust the cognitive distortions and behavioural dysfunctions related to eating habits and weight. By doing so the patients reduce their concerns regarding their body and the dieting behaviour. Moreover, in this phase, the therapist uses a schema-based approach that analyses and modifies other problems that affect the psychological well-being of the patients. The last phase of the cognitive behavioural therapy for bulimia nervosa focus on maintaining the learnt healthy behaviours and prevent future episodes of binge eating and purging. At the end of the last session, participants are provided with a personalised programme that will help them to prevent the chances of relapse. CBT is usually administrated individually, however, therapists can decide to conduct a group-intervention. Despite these phases are presented in a sequence in the manual, in reality, it is up to the clinician to decide the series of the phases, based on the personality of the patient and the severity of the symptoms. For instance, if at a certain point during the therapy treatment the patient returns to frequently binge eating and purging, then the clinician will shift the focus of the therapy session back to the first or second phase.
Several studies have attempted to assess the efficiency, validity and reliability
of CBT in
treating and preventing bulimia nervosa. In a study that compared the effectiveness of Cognitive-Behavioural Therapy and Interpersonal Psychotherapy (IPT), the researchers found several interesting results. Firstly, according to their finding, only 8%, of the bulimic patients who have been treated with IPT stopped binge eating and purging, compared to the 45% of patients treated with CBT (Agras, Walsh, Fairburn, Wilson & Kraemer, 2000). Moreover, at the end of the treatment sessions, the results suggested that CBT had a stronger effect in reducing self-induced vomiting and dietary restraint. Therefore, while with other mental disorders (e.g. depression) CBT and IPT seem to have similar positive outcome (Elkin et al., 1989), in the case of bulimia nervosa, cognitive behavioural therapy has a superior treatment effect compared to Interpersonal Psychotherapy, especially in reducing the primary behavioural symptoms of BN. These studies are comparable with several other researches that have investigated as well, the efficacy of CBT for BN using similar assessment. The median rate of cessation of binge eating and self-induced vomiting and reduction of weight and body-shape concerns was 45% (ranging between 19%-64%) (Fairburn, 1991; Walsh et al., 1997; Garner et al., 1993; Cooper & Steere, 1995; Wilson, Eldredge, Smith & Niles, 1991).
In 2012, instead, Grilo and colleague examined and compared the long-term efficacy of CBT and of an SSRI antidepressant (fluoxetine) for BN. They continued monitoring the patients for 12-months after completing the treatments. The subjects have been allocated to one of the three treatment conditions: fluoxetine-only, CBT + fluoxetine, and CBT + placebo. The results of their study suggested that CBT + fluoxetine (26.9%) and CBT + placebo (35.7%) had similar positive remission rates, which were significantly superior compared to the fluoxetine-only condition (3.7%). Therefore, based on their findings it appears that when it comes to long-term effectiveness for reducing the binge-eating behaviour, CBT can be considered as a suitable intervention. However, a limitation of this study was that the participants were mainly white, well-educated females; therefore, it might be that with a more diverse group of patients, the results would have been different. Based on the outcomes of these studies, CBT appears to be faster compared to antidepressant drugs in ameliorating the primary symptoms of BN.
As a result of accumulated research, CBT is now believed to be the preferred treatment for BN (e.g. American Psychiatric Association Work Group on Eating Disorders Washington, 2000; Dingemans, Bruna, & van-Furth, 2002; Mizes & Bonifazi, 2000; National Institute for Clinical Excellence, 2004; Wilson & Fairburn, 2002). For instance, Fairburn, in 1995, conducted a research where he looked at the long-term effectiveness of BN (length of follow-up, 5.8 +/- 2.0 years). The results showed that 54% of the patients reported being in remission throughout the whole follow-up period, two other patients relapsed during the first year of follow-up and two patients were remitted in the first 12 months. Indeed, the numbers are really promising, and despite this study has not been replicated, in a similar research, conducted five years later, the researchers found consistent results as 21 patients out of the 32 did not experience a relapse after the first year. Moreover, still in support of the efficiency of CBT, a quite recent study argued that CBT does increase the remission rate from 20% to 32% over a period of 12 months (Le Grange, Lock, Agras, &Bryson, 2015). However, despite this result seems really promising, the study does have some limitations. For instance, the patients’ age ranged from 12 to 18 years old; therefore, perhaps future researchers might attempt to replicate the study using adults as participants. Moreover, 59% of the patients still continued to receive treatment throughout the follow-up period. Consequently, this factor might have influenced the positive results of the research. To conclude, based on the evidences provided in these studies, it can be argued that CBT can be considered as the first-line therapy for bulimia nervosa (Hay, 2013).
It can be noticed, however, that this specific treatment is insufficiently helpful for a significant proportion of patients, as not every patient cease binge eating and purging. This partial inefficiency can be due to some methodological limitations, as they might have influenced the overall results of these studies, and consequently might have negatively affect the way cognitive behavioural therapy is structured. perhaps CBT might not have such greater effect on bulimia patients compared to other treatment methods due to these methodological limitations For instance, if we analyse in more details these studies, it can be argued that it is significantly more challenging for researchers to recruit participants for this type of researches, due to medical complications and the high rate of dropout (Swift and Greenberg, 2014; Zaitsoff et al., 2015). Therefore, calculation of power or effect size is usually quite low. Moreover, the few participants that take part in this type of researches are usually females, since bulimia nervosa is nine times more likely to occur in women (1.5% of women will struggle with bulimia in their lifetime; 3.5% of women will struggle with binge eating) than men (.5% of men will struggle with bulimia; 2% of men will struggle with binge eating disorder) (The National Institute of Mental Health, 2002). Therefore, future studies might look more specifically If women with bulimia nervosa and men who suffer from the same eating disorder do react differently to cognitive behavioural therapy, and if so then new gender-specific treatments can be developed. Another factor in the researches’ samples that might have influenced the effectiveness of the cognitive-behavioural treatment is the age of the participants. As previously argued, adolescents with BN tend to have higher chances of recovery if they are subjected to family therapy (Le Grange, 2010). However, some studies who analysed the effect of CBT on BN used as sample both adolescents and adults. Therefore, as people with bulimia nervosa tend to respond differently to treatments based on their age, future research might investigate to what extent and how in particular adults and adolescents with BN respond differently to CBT. Ethnicity is another factor that could have influenced the results, as most studies on this topic tends to have mainly white/Caucasian participants. Wildes, Emery and Simons (2001) argued that this ethnical prevalence is due to the fact that white people tend to be more prone to develop BN than non-white population (Striegel-Moore, Dohm, Kraemer, Taylor, Daniels et al., 2003; Alegria, et al., 2007). However, it would be interesting to understand the reasons behind this ethnical difference, as its understanding might be useful to comprehend the causes behind its development and consequently how to prevent it. To conclude, another factor that could have influenced the outcome of cognitive behavioural therapy is that researchers, in most cases, did not take into account whether participants have been previously exposed to this or another type of therapy or if they had any knowledge about them. These factors need to be controlled in future studies as it is possible that they might have influenced the reported efficiency of CBT, moreover a deeper knowledge on the matter can result in higher chances of developing an even more effective version of CBT for BN.
Another supposition is that, perhaps, if we make certain considerations, CBT might not have such greater effect on bulimia patients compared to other treatment methods. For instance, studies that have reported measures of statistically significant improvements do not imply that the patients have had a clinically significant change. Perhaps, their bulimic attitudes did change thanks to the CBT intervention, however, they might still engage in binge eating and se
lf-induc
ed vomiting (Openshaw, Waller and Sperlinger, 2004). Moreover, the obtained results suggesting that CBT reduces dramatically the number of times patients engage in these unhealthy behaviours, seem really promising. However, these patients used to engage in binge eating and purging multiple times daily, therefore even if the frequency of these behaviours reduced by 50% their behaviour still remain symptomatic (Braun, 2009). Future researches should take these considerations into account in their next studies, in order to obtain more accurate conclusions.
This critical review had analysed the effectiveness of cognitive behavioural therapy in helping people with bulimia nervosa. The results of several studies seem to suggest the CBT is able to reduce the bulimic symptoms in most cases. Moreover, compared to other treatment methods, CBT has provided the most positive results in terms of relapse rate and reduction of symptoms. It has been argued, however, that not every bulimic person treated with CBT remitted completely, thus its method still needs improvements. This could be due to methodological limitations (e.g. the participants are mainly white, well-educated, young females), that limit the generalisation of the results, and do not allow to verify if CBT needs different variations based on the type of patient (e.g. female vs. male). Therefore, future researches should verify if by adapting the treatment to the different characteristics of the patients (e.g. culture, family background, ethnicity) then the general remittance rate would increase.