Commentary on the paper "Is alexithymia a risk factor for major depression, personality disorder, or alcohol use disorders? A prospective population-based study"

[Alexithymia in Multiple Sclerosis - Narrative Review]

Alexithymia is a multidimensional construct of personality implicating difficulties in identifying and describing another's feelings, and externally oriented thinking. It is broadly reported in psychiatric patients but has gained little attention regarding its occurrence and pathophysiology in multiple sclerosis (MS). This narrative review aims to address prevalence, etiology, neurobiological, and clinical findings of alexithymia. The prevalence of alexithymia in MS ranges from 10 to 53%. There seems to be an association with anxiety, depression, fatigue, and some aspects of social cognition, while the relationship with clinical and classical cognitive variables was rarely evaluated. Only a few studies referred to its pathophysiology assuming an aberrant interhemispheric transfer or regional cerebral abnormalities. The prevalence of alexithymia in MS and the potential negative impact on quality of life and interpersonal communication could severely impact clinical MS management and a screnning for these factors should be mandatory. Thus, further evaluation is needed concerning its relationship with clinical, emotional, and cognitive confounders. Large-scale studies employing neuroimaging techniques are needed for a better understanding of the neural underpinnings of this MS feature.

Associations between socioemotional alterations, quality of life, and social functioning in multiple sclerosis: A scoping review

The main aim of the present scoping review is to systematically review the available studies that investigated the associations between socioemotional alterations (i.e., social cognition impairments/alexithymia/difficulties in emotion regulation) and both reduced QoL and social functioning in patients with Multiple Sclerosis (MS). The articles were selected from the PubMed, PsycINFO, and Scopus databases. The main exclusion criteria were qualitative studies, articles that did not use validated instruments, and studies that did not investigate the association between socioemotional skills and QoL/social functioning in MS. Of the eight studies fulfilling the inclusion criteria, six found significant associations between social cognitive and emotion regulation abilities and QoL/social functioning in patients with MS, while two found no significant relationships particularly between the performance on social cognition tasks and QoL measures. Overall, the majority of findings seem to highlight that socioemotional alterations contribute to impaired QoL and social functioning in MS. However, given the still limited evidence, future studies are needed to replicate and confirm the available results, paying attention to two principal aspects: the use of standardized and ecological tasks for the assessment of social cognition skills and the recruitment of samples involving patients with different types of MS.

Impaired cognitive self-awareness mediates the association between alexithymia and excitation/inhibition balance in the pgACC

BACKGROUND

Previous research showed that automatic emotion regulation is associated with activation of subcortical areas and subsequent feedforward processes to cortical areas. In contrast, cognitive awareness of emotions is mediated by negative feedback from cortical to subcortical areas. Pregenual anterior cingulate cortex (pgACC) is essential in the modulation of both affect and alexithymia. We considered the interplay between these two mechanisms in the pgACC and their relationship with alexithymia.

METHOD

In 68 healthy participants (30 women, age = 26.15 ± 4.22) we tested associations of emotion processing and alexithymia with excitation/inhibition (E/I) balance represented as glutamate (Glu)/GABA in the pgACC measured via magnetic resonance spectroscopy in 7 T.

RESULTS

Alexithymia was positively correlated with the Glu/GABA ratio (N = 41, p = 0.0393). Further, cognitive self-awareness showed an association with Glu/GABA (N = 52, p = 0.003), which was driven by a correlation with GABA. In contrast, emotion regulation was only correlated with glutamate levels in the pgACC (N = 49, p = 0.008).

CONCLUSION

Our results corroborate the importance of the pgACC as a mediating region of alexithymia, reflected in an altered E/I balance. Furthermore, we could specify that this altered balance is linked to a GABA-related modulation of cognitive self-awareness of emotions.

Predicting symptoms in major depression after inpatient treatment: the role of alexithymia

Alexithymia has been considered to have a negative influence on the course of symptoms in various psychiatric disorders. Only a few studies of depressed patients have examined whether alexithymia predicts the outcome of therapeutic interventions or the course of symptoms in naturalistic settings. This prospective study investigated whether alexithymia is associated with depressive symptoms after a multimodal inpatient treatment. Forty-five inpatients suffering from acute major depression were examined in the initial phase of treatment and then again after seven weeks. Patients took part in a multimodal treatment programme comprising psychodynamic-interactional oriented individual and group therapy. The majority of patients were taking antidepressants during study participation. To assess alexithymia and depressive symptoms, the 20-item Toronto Alexithymia Scale (TAS-20), the Beck Depression Inventory II (BDI-II) and the Hamilton Depression Scale (HAMD) were administered at baseline and follow-up. When controlling for baseline depressive symptoms along with trait anxiety, high scores in the externally oriented thinking (EOT) facet of alexithymia at baseline predicted high severity of depressive symptoms at follow-up (for self-reported as well as interviewer-based scores). Inpatients suffering from major depression with a more pronounced external cognitive style might benefit less from a routine multimodal treatment approach (including psychodynamic interactional therapy, antidepressant medication, and complementary therapies). Intervention programmes might modify or account for alexithymic characteristics to improve the course of depressive symptoms in these patients.

Is alexithymia associated with metabolic syndrome? A study in a healthy adult population

Metabolic syndrome (MetS) is a constellation of risk factors for, in particular, cardiovascular diseases and increased mortality, and it constitutes a major clinical challenge affecting millions of lives. Alexithymia is a condition that has been linked with several mental diseases and symptoms, as well as somatic illnesses, including essential hypertension and diabetes mellitus. However, there is limited research on the association of alexithymia and MetS. The aim of the present study was to comprehensively explore this association in a large (n=1648) non-clinical sample of adults. Logistic regression analyses were applied to the five separate MetS components as well as the MetS diagnosis, and the analyses included a number of sociodemographic variables and depressive symptoms as covariates. The results confirmed the previous finding of alexithymic features being independently and significantly associated with hypertension. As a new finding, this association appears to be related to two particular dimensions of alexithymia, namely difficulty describing feelings and externally oriented thinking. Interestingly, alexithymic features were also separately significantly associated with waist circumference and triglycerides as well as the MetS diagnosis. Depressive symptoms did not have any significant effect on the relations of alexithymia and MetS.

The role of alexithymia in predicting incident depression in patients at first acute coronary syndrome

OBJECTIVE

Alexithymia has been considered both to predispose to depression and to worsen cardiac prognosis after an acute coronary syndrome. Nonetheless, no studies have evaluated its role as a risk factor for incident depression, in patients with acute coronary syndrome.

METHODS

In 251 consecutive patients, the presence of a first-ever depressive episode was evaluated with the Primary Care Evaluation of Mental Disorders at baseline and 1, 2, 4, 6, 9, 12 and 24 months after their first acute coronary syndrome. At baseline, patients completed the Toronto Alexithymia Scale (TAS-20) and the Hospital Anxiety and Depression Scale.

RESULTS

Out of 251 subjects (80.9% males), a first-ever depressive episode was diagnosed in 66 patients. Depressed and never-depressed patients differed in female gender, living status, alexithymic scores at TAS-20 and depressive symptoms. Nonetheless, nor the TAS-20 factors nor its total score were predictive of developing a depressive episode in a Cox regression. Moreover, baseline differences in TAS-20 scores between the two groups, disappeared after controlling for anhedonic symptoms.

CONCLUSION

Our results do not support the hypothesis that alexithymia at TAS-20 is a risk factor for incident depression after acute coronary syndrome.

Does alexithymia expose to mental disorder symptoms in late adolescence? A 4-year follow-up study

OBJECTIVE

To investigate the possible causal link between alexithymia and the emergence of anxiety and depression symptoms, as well as alcohol consumption in a sample of late adolescents.

METHOD

The nonclinical sample comprised late adolescents (n = 315), including both females (n = 256) and males (n = 59). The follow-up period was 4 years, and at baseline, the mean age of the subjects was 19 years (range 17-21 years). Alexithymia was measured with the 20-item Toronto Alexithymia Scale (TAS-20), depression symptoms with the short form of the Beck Depression Inventory (RBDI), anxiety with the State-Trait Anxiety Inventory (STAI) and alcohol consumption with the Alcohol Use Disorders Identification Test (AUDIT). The three TAS-20 subscales were assessed separately. Linear and cumulative logistic regression analyses were used for the evaluation of associations, and the analyses were adjusted with the corresponding baseline scores.

RESULTS

The TAS-20 total and subscale scores did not predict the RBDI or AUDIT scores at follow-up. However, the TAS-20 subscale "difficulty identifying feelings" was significantly associated with both STAI-State (P = .007) and STAI-Trait (P = .004) scores at follow-up.

CONCLUSIONS

Alexithymic features may be individual predictors of later anxiety symptoms. The significant differences between the various dimensions of alexithymia should be considered in future studies.

Music in depression: Neural correlates of emotional experience in remitted depression

AIM: To investigate neural and behavioral correlates of emotional experiences as potential vulnerability markers in remitted depression.

METHODS: Fourteen remitted participants with a history of major depression and fourteen closely matched healthy control participants took part in the study. We used two psychiatric interviews (Hamilton Depression Rating Scale, Montgomery-Asberg Depression Rating Scale) and one self-report scale (Beck Depression Inventory) to assess remission. Healthy control participants were interviewed by an experienced psychiatrist to exclude those who showed any current or lifetime psychiatric or neurological disorders. To explore psychosocial and cognitive-interpersonal underpinnings of potential vulnerability markers of depression, early life stress, coping styles and alexithymia were also assessed. We induced pleasant and unpleasant emotional states using congruent combinations of music and human emotional faces to investigate neural and behavioral correlates of emotional experiences; neutral stimuli were used as a control condition. Brain responses were recorded using functional magnetic resonance imaging. Behavioral responses of pleasantness, arousal, joy and fear were measured via button-press inside the resonance imaging scanner.

RESULTS: The mean age of the sample was 54.9 (± 11.3) years. There were no differences between remitted depressed (RD) (n = 14; 9 females and 5 males) and healthy participants (n = 14; 8 females and 6 males) regarding age, current degree of depression, early life stress, coping styles and alexithymia. On a neural level, RD participants showed reduced activations in the pregenual anterior cingulate cortex (pgACC) in response to pleasant [parameter estimates: -0.78 vs 0.32; t(26) = -3.41, P < 0.05] and unpleasant [parameter estimates: -0.88 vs 0.56; t(26)= -4.02, P < 0.05] emotional stimuli. Linear regression analysis revealed that pgACC activity was modulated by early life stress [β = -0.48; R² = 0.23, F(1,27) = 7.83, P < 0.01] and task-oriented coping style [β = 0.63; R² = 0.37, F(1,27) = 16.91, P < 0.001]. Trait anxiety modulated hippocampal responses to unpleasant stimuli [β = 0.62; R² = 0.38, F(1,27) = 15.95, P < 0.001]. Interestingly, in their reported experiences of pleasantness, arousal, happiness and fear in response to pleasant, unpleasant and neutral stimuli, RD participants did not differ significantly from healthy control participants. Adding trait anxiety or alexithymia as a covariate did not change the results.

CONCLUSION: The present study indicates that, in euthymic individuals, depression history alters neural correlates, but not the subjective dimension of pleasant and unpleasant emotional experiences.

How emotional abilities modulate the influence of early life stress on hippocampal functioning

Early life stress (ELS) is known to have considerable influence on brain development, mental health and affective functioning. Previous investigations have shown that alexithymia, a prevalent personality trait associated with difficulties experiencing and verbalizing emotions, is particularly related to ELS. The aim of the present study was to investigate how neural correlates of emotional experiences in alexithymia are altered in the presence and absence of ELS. Therefore, 50 healthy individuals with different levels of alexithymia were matched regarding ELS and investigated with respect to neural correlates of audio-visually induced emotional experiences via functional magnetic resonance imaging. The main finding was that ELS modulated hippocampal responses to pleasant (>neutral) stimuli in high-alexithymic individuals, whereas there was no such modulation in low-alexithymic individuals matched for ELS. Behavioral and psychophysiological results followed a similar pattern. When considered independent of ELS, alexithymia was associated with decreased responses in insula (pleasant > neutral) and temporal pole (unpleasant > neutral). Our results show that the influence of ELS on emotional brain responses seems to be modulated by an individual's degree of alexithymia. Potentially, protective and adverse effects of emotional abilities on brain responses to emotional experiences are discussed.

The association of interoceptive awareness and alexithymia with neurotransmitter concentrations in insula and anterior cingulate

Alexithymia and increased interoceptive awareness have been associated with affective disorders as well as with altered insula and anterior cingulate cortex (ACC) function. Brain imaging studies have demonstrated an association between neurotransmitter function and affective disorders as well as personality traits. Here, we first examined the relationship between alexithymic facets as assessed with the Toronto Alexithymia Scale (TAS-20) and interoceptive awareness (assessed with the Body Perception Questionnaire) in 18 healthy subjects. Second, we investigated their association with glutamate and gamma-aminobutyric acid (GABA) concentrations in the left insula and the ACC using 3-Tesla proton magnetic resonance spectroscopy. Behaviorally, we found a close association between alexithymia and interoceptive awareness. Furthermore, glutamate levels in the left insula were positively associated with both alexithymia and awareness of autonomic nervous system reactivity, while GABA concentrations in ACC were selectively associated with alexithymia. Although preliminary, our results suggest that increased glutamate-mediated excitatory transmission-related to enhanced insula activity-reflects increased interoceptive awareness in alexithymia. Suppression of the unspecific emotional arousal evoked by increased awareness of bodily responses in alexithymics might thus be reflected in decreased neuronal activity mediated by increased GABA concentration in ACC.