Discussion
guilt, HAMD, cognitive distortions, depressive, depressive symptoms, MDD, depression, AD
DTS, REMISSION
This study investigated whether dysfunctional thoughts mediated depressive symptoms. The study found that dysfunctional thoughts were not only correlated with depressive symptoms but also, moderated some results. The major finding indicated that the perception of self and future (F1) and the perception of the world and others (F2) in W8 mediated the relationships between the perception of depression symptoms (BDI-II) and severity of depression symptoms (MADRS and HAMD) in W12, i.e., those with dysfunctional interpretations of themselves, the world, and others in W8 have a more negative symptomatology response in W12.This way, patients who had more dysfunctional interpretations of themselves, the world, and others in the second month of treatment tended to have a more negative symptomatologic response in the fourth month. These findings support the tripartite model proposed by Beck, indicating that thoughts can mediate depression severity [Since these results differ from the longitudinal study by Quigley et al. [Although depressive symptoms were in remission by week 8 and patients were characterized as having “limited” distortions by the DTS manual at week 12, their scores when compared to a non-clinical group are labeled as “very distorted,” i.e., they continue to display important dysfunctional thinking when compared to healthy controls. Results were different from Quigley et al. [Neither the perception about themselves or the future (DTS-F1) nor their relationships (DTS- F2) in 2 months mediated the depression severity measured by the HAMD or MADRS scales at the end of the 6 months. On the other side, for BDI-II, results indicated that dysfunctional thoughts mediate the severity of depression during the treatment. An important implication of the current findings is related to the scales; once symptoms have been operationalized, they vary considerably.The differences between DTS and the rating scales (HAMD and MADRS) were expected, considering that only two HAMD items (feelings of guilt and suicide) and two MADRS items (pessimistic thoughts and suicidal thoughts) can be considered relevant to cognitive distortions. On the other hand, the BDI-II contains eight relevant items, i.e., 1/3 of the inventory items (pessimism, past failure, guilty feelings, punishment feelings, self-dislike, self-criticalness, suicidal thoughts or wishes, and worthlessness), and was developed by Beck, which could explain the mediation effects.As symptoms decrease, thoughts become more prominent, demonstrating the distinction between symptomatic remission and full recovery, an important aspect when treating depression, as discussed in previous studies [In fact, negative self- and future perceptions have been proven to be linked with depressive symptoms. This finding is consistent with Wang et. [Research has already found that cognitive distortions persist not only in remitted people but are also considered predictors of depression chronicity [This study has strengths and weaknesses. Regarding strengths, this is one of the first studies to use a specific scale based on Beck’s Cognitive Triad Theory with a sample of MDD patients without comorbidities over a 6-month period. The study also has important implications for depression, suggesting that future treatments should look for cognitive distortions as an important feature for early detection of MDD. Once results show that when AD is used to treat depression, distorted thoughts do get less, but not as much as was needed, maybe distorted thinking responses should be viewed in a new light: as more than a state, as a trait.The current study had limitations, including the small sample and the sample dropout rates, which were significant (around 80%). Although those rates are not expected in North America or Europe longitudinal studies (around 30-40%), they could be found in other recently published Brazilian studies. As discussed, one of the highest reasons for poor adherence was related to a drug-related factor (tolerance, and monotherapy), followed by patient-related variables (economic status) and physician-related factors (communication and lack of psychoeducation to promote treatment adherence).Another limitation was the absence of control groups, which would have allowed us to determine if another treatment, such as CBT or psychoeducation, could impact a better DTS score response and adherence to the study. To keep the study as close to understanding and evaluating the assumptions of the cognitive model as possible, we excluded patients undergoing psychotherapy, but one of the possible reasons for dropout could be attributed to a lack of psychoeducation, a variable that we did not control.