Table 2.
Studies investigating the impact of alexithymia on treatment outcome in eating disorders.
| Reference | Objectives | Study design | Sample size | Standardized assessments of alexithymia | Treatment | Assessment tools | Diagnosis | Results |
|---|---|---|---|---|---|---|---|---|
| Schmidt et al. (34) | To investigate alexithymia prevalence among individuals affected by DSM-III defined eating disorders as compared with healthy controls (1), eventual differences in alexithymia prevalence among the included nosological categories (2), alexithymia persistence in these conditions (3), the predicting value of alexithymia for short-term treatment outcome (4) | Combination of cross-sectional study and of a 10-week double blind placebo-controlled trial | (a)173 F cases (93 BN, 55 AN/R, 25 AN/BN); 95 healthy controls (48 F, 47 M). (b)41 F individuals affected by BN |
a. TAS-26 b. TAS-26 |
(b) Fluoxetine vs placebo | a. BITE, BSQ b. BITE, BSQ, HAM-D |
AN/RN, AN/BN, BN | (a)Cases had a significantly higher alexithymia prevalence than controls. TAS did not correlate with BMI, BITE, BSQ. (b)TAS at t0 correlated with TAS at t1 but did not correlate to any other variable. TAS at t1 positively correlated with rater-assessed binge. |
| de Groot et al. (35) | To estimate alexithymia prevalence among women affected by DSM-III defined BN treated in a DH (1), alexithymia relationship with somatic symptoms and depression (2), efficacy of group psychotherapy in reducing alexithymia burden | Prospective study with assessments pre- and post-treatment; case control analysis with a comparison group assessed at 1 point only | 31 cases, 20 controls | TAS-26 | Psychotherapeutic group focusing on body image, nutrition, family interactions and symptoms management (average duration of treatment 9.6 weeks) | BDI, EDE, EDI | BN | A greater proportion of BN affected individuals presented alexithymia as compared with healthy controls before treatment (t0); post-treatment (t1) there was a significant reduction in alexithymia proportion among BN individuals, but it persisted at a higher level than the comparison group |
| Beales et al. (36) | To explore the presence of alexithymic features in a selected group of individuals affected by ED and the potential implications of the said features for the primary care setting | Survey | 79 | TAS-20 | EDI-2, 16-PF5, | AN/R, BN and RV | A higher prevalence of alexithymia was found among AN/R and BN groups as compared with the R group; 16PF5 social skills domain negatively correlated with alexithymia | |
| Becker-Stoll et al. (37) | To investigate the potential efficacy of an intensive 4-month intervention program on alexithymia in ED (DSM-IV defined) and the possible alexithymia role in predicting treatment outcome | Prospective design with assessments performed before (t0) and after treatment (t1) | 47 | TAS-20 | A 4-month psychotherapeutic program employing interpersonal, cognitive-behavioral and psychoeducational methods. | EDI | AN, BN, EDNOS | There was a significant reduction in both EDI-2 and TAS-20 (especially DIF) at T1. TAS-20 score at T1 correlated with EDI2 at T1 and with a worse prognostic outlook; there was no significant correlation between TAS at t1 and the recovery state |
| Shiina et al. (38) | To study the efficacy of a CGCBT for BN affected individuals in the outpatient setting, further exploring the characteristic of individuals failing to respond under such treatment | Prospective design with assessments at the beginning (T0) and at the end of the treatment course (T1) | 25 | TAS-20 | 1-h weekly sessions of CGCBT over a 10-week period, including diet psychoeducation, social skill training, self-esteem enhancement, coping training for interpersonal problems | BITE, CGI-C, CGI-S, EDI-2, GAF, HAM-D, RSES | BNP, ANBP, BNNP, EDNOS | Among the 16 individuals that completed the treatment course, at T1 there was a significant reduction in BITE, GAF, EDI-2, RSES scores as compared with T0; mean TAS-20 scores showed a non-significant reduction (p= 0.06). No significant association was found between TAS-20 and treatment outcome. |
| Speranza et al. (39) | To investigate the influence of alexithymia on treatment outcome in a large sample of ED affected individuals | 3-year longitudinal study | 102 | TAS-20 DIF, DDF, EOT | Due to the naturalistic study design no treatment was specifically recommended; of the total sample 57% was undergoing psychotherapy, 40% was on antidepressants | MINI, BDI-13, CGI-S, PSRS | ED | At the 3-year follow-up assessment 76 patients were judged to have an unfavourable prognosis with DIF being a significant predictor of a negative outcome |
| Tchanturia et al. (40) | To explore the complex interplay between ED, social anhedonia and alexithymia | Observational study | 148 | TAS-20 DIF, DDF, EOT | Due to the observational nature of the study, no specific treatment was recommended | SCID for DSM-IV, DASS, EDE-Q, RSAS | AN, BN | A positive correlation was described between social anhedonia and alexithymia |
| Balestrieri et al. (41) | To explore the efficacy of a 10-week psychoeducational group program among BED and EDNOS affected individuals, and the persistence of its eventual benefits | A 1-year follow-up study with assessments before treatment (T0), after treatment (t1) and at 1-year follow up (T2) | 98 | TAS-20 | 10-week psychoeducational group including nutritional interventions and thoughts related to eating disorder along with assertiveness training. After the first 10-weeks, those individuals still satisfying ED criteria were involved in a further extension protocol comprising 8 additional monthly sessions | EDI-2, EDI-SC, HADS | BED, EDNOS | A lower or absent alexithymia level was associated with a higher likelihood of responding to treatment |
| Ohmann et al. (42) | To explore emotional problems of young individuals affected by AN and undergoing GCBT | A 12-month follow-up study with assessments before treatment (T0), during treatment (at 3 and 6 months, T1 and T2, respectively), and post-treatment (T3) after 12 months | 29 | TAS-26 | GCBT focusing on psychoeducation, schema psychotherapy, communication skill training, problem analysis, therapeutic motivation, hedonistic training, problem solving (5 individuals were concomitantly treated with antidepressants) | ASW, BDI, JTCI, MDI, YSR | AN | Only two patients described themselves as not alexithymic. Alexithymia presented a non-significant trend toward improvement in responding individuals. |
16PF5, Sixteen Personality Factor Questionnaire 5th Edition; AN/RN, Anorexia Nervosa/Restrictive subtype; AN/BN, Anorexia Nervosa/Bulimic subtype; NBP, Anorexia Nervosa Binge-eating/Purging type; ASW, Assessment of Self-Efficacy; BDI-13, Beck Depression Inventory 13 items version; BITE, Bulimic Investigatory Test; BMI, Body Mass Index; BNNP, Bulimia Nervosa Non-Purging type; BNP, Bulimia Nervosa Purging type; BSQ, Body Shape Questionnaire; CGCBT, Combined Group Cognitive Behavioral Therapy; CGI-C, Clinical Global Impression Change; CGI-S, Clinical Global Impression Severity; DIF, TAS-20 factor 1 Difficulty Describing Feelings; DDF, TAS-20 factor 2 Difficulty Identifying Feelings; DSM-III, Diagnostic and Statistical Manual of Mental Disorders III-edition; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders IV-edition; ED, eating disorders; EDE-Q, Eating Disorder Examination Questionnaire; EDI-2, Eating Disorder Inventory-2; EDI-SC, Eating Disorder Inventory-Symptom Checklist; EDNOS, eating disorder not otherwise specified; EOT, TAS-20 factor 3 Externally Oriented Thinking; GCBT, Group Cognitive Behavioral Therapy; HADS, Hospital Anxiety and Depression Scale; HAM-D, Hamilton Depression Rating Scale; HC, healthy control; JTCI, Junior Temperament and Character Inventory; MDI, Marburg Diagnostic Inventory; MINI, Mini International Neuropsychiatric Interview; PSRS, Psychiatric Status Rating Scale; RAN, recovered anorexia nervosa; RSAS, Revised Social Anhedonia Scale; RSES, Rosenberg Self-Esteem Scale; RV, recovered; SPS, Social Phobia Scale; SIAS, Social Interaction Anxiety Scale; TAS-20, Toronto Alexithymia Scale-20; YSR, Youth Self Report.