عوامل پیش بینی و گرداننده گان نتایج عصبی شدید و بی اشتهایی پایدار

Few of the limited randomized controlled trials (RCTs) for adults with anorexia nervosa (AN) have explored predictors and moderators of outcome. This study aimed to identify predictors and moderators of outcome at end of treatment (EOT) and 6- and 12-month follow-up for adults with AN (N = 63). All participants met criteria for severe and enduring AN (duration of illness ≥ 7 years) and participated in an RCT of cognitive-behavioral therapy (CBT-AN) and specialist supportive clinical management (SSCM). General linear models were utilized and included all available outcome data at all time points. Outcome was assessed across three domains: eating disorder quality of life (EDQOL), mental health (MCS), and depressive symptoms (BDI). Predictors of better outcome included: lower age, shorter duration of illness, having AN-R, being employed, not taking psychotropic medication, and better social adjustment. Four moderators of treatment outcome emerged: eating disorder psychopathology (EDE Global), depression (BDI), age, and AN subtype. Participants with higher baseline scores on these measures, older age, or binge eating/purging subtype benefited more from CBT-AN than SSCM. Older patients with more severe eating-related psychopathology and depression have better outcomes in a behaviorally targeted treatment such as CBT-AN rather than a supportive treatment such as SSCM.

Few randomized controlled trials (RCTs) examining different psychosocial treatments for adults with anorexia nervosa (AN) have been conducted (e.g., Dare et al., 2001, Lock et al., 2013a, McIntosh et al., 2005, Pike et al., 2003 and Russell et al., 1987). Most of these studies are compromised through lack of statistical power, and findings are generally inconclusive. The most recent published RCT for this patient population compared the relative efficacy of cognitive-behavioral therapy (CBT-AN) to specialist supportive clinical management (SSCM) in 63 women with severe and enduring anorexia nervosa (SE-AN). While this study was also compromised due to a modest sample size, satisfactory retention in treatment and follow-up was achieved (85% of patients remained in treatment and follow-up). This study demonstrated that patients with SE-AN could make significant and meaningful improvements with both therapies. Both CBT-AN and SSCM contributed to improvements over time in several outcome domains: health-related quality of life, body weight, depression, and motivation to change (Touyz et al., 2013). Kraemer, Wilson, Fairburn, and Agras (2002) remind us that while the evaluation of the relative efficacy of two or more treatments in an RCT is helpful, our understanding for whom a specific treatment may be best suited for (moderators of outcome), or the mechanisms through which a treatment might achieve its aims (mediators on outcome), has significant clinical relevance. Few, if any, of the published RCTs for adults with AN have examined moderators and mediators on outcome. Some of the RCTs for adults with AN have examined predictors of treatment outcome. In a study of 33 females with AN treated with CBT or nutritional counseling, Pike et al. (2003) found no significant effect of medication status on outcome for those treated with nutritional counseling. They did find a medication effect for CBT in that seven out of eight patients who met criteria for a good outcome were receiving medication compared to four of ten who did not meet criteria for good outcome. McIntosh et al. (2005) randomized 56 females with AN to CBT, SSCM or interpersonal therapy (IPT). These authors found that differences in outcome among the treatment groups were not explained by any difference among treatment groups at baseline. Outside of RCTs, moderators on treatment outcome have also received some attention. Lockwood, Serpell, and Waller (2012) examined moderators of weight gain in the early stages of treatment for 40 females with AN receiving CBT. They found that neither age nor body mass index (BMI) at the start of therapy predicted degree of weight change during the first 10 sessions of CBT. However, participants with elevated anxiety or phobic anxiety were slower to gain weight in the first 10 sessions (or even lost weight), and more severe levels of dietary restraint and shape concern were associated with lower levels of weight change from sessions 6–10. In a study of 218 adults with either BN or BED receiving CBT, Castellini et al. (2011), showed that eating psychopathology, psychiatric comorbidity, impulsivity and emotional eating differ in their association with both objective and subjective binge eating across BN and BED patients. Most recently, Lock, Agras, Le Grange, et al. (2013) demonstrated that for adults with AN, the most efficient predictor of weight recovery at follow-up (BMI > 19 kg/m2) was weight gain to greater than 85.8% of expected body weight at the end of treatment. In addition, the most efficient predictor of psychological recovery was achievement of a low score on the Eating Disorder Examination (EDE) Weight Concern subscale (<1.8). Exploring mediators and moderators of outcome for adolescents with AN has been equally limited (Eisler et al., 2000, Le Grange et al., 1992, Lock et al., 2005 and Lock et al., 2006). In the largest such study to date, Le Grange et al. (2012), were able to identify at least two moderators at end-of-treatment: eating-related obsessionality (Yale–Brown–Cornell Eating Disorder Total Scale) and eating disorder specific psychopathology (EDE Global). In an RCT of family-based treatment (FBT) and adolescent focused therapy (AFT), participants with higher baseline scores on these measures benefited more from FBT than AFT. No mediators of treatment outcome were identified. Taken together, it is clear that the treatment of AN is not only hampered by a limited number of RCTs, but also by the lack of studies exploring for whom treatments work best, or how one treatment versus another brings about therapeutic change. In the present study we examine predictors and moderators of outcome (i.e., eating disorder-related quality of life, mental health, depressive symptoms) for participants in the RCT of CBT-AN and SSCM briefly described above. Given the scarcity of prior work in this domain, we did not advance any specific hypotheses. Rather, we chose to investigate several variables as possible predictors and moderators, and our procedure was therefore an exploratory analysis. Findings should thus be regarded as hypothesis generating as opposed to hypothesis testing.

This study identified four moderators of treatment outcome: EDE Global scores, BDI scores, age, and AN subtype. For each moderator, whether it is higher eating disorder psychopathology, poorer mood, older age, or a binge/purge profile, patients did better if they received CBT-AN rather than SSCM. While it is helpful to have identified a subset of patients for whom CBT-AN would be advantageous, it was disappointing that no such patient group was identified for SSCM. Larger samples and interviewer-based outcome measures may strengthen future studies and will increase power and provide a better opportunity to detect such moderation. Findings from this study are exploratory in nature but nevertheless provide an important rationale for testing specific moderation and mediation effect hypotheses in future studies. If such studies are feasible, heterogeneous treatment effects on outcome for patients in different treatments and with different levels of psychopathology can be examined.