Alexithymia and Somatosensory Amplification Link Perceived Psychosocial Stress and Somatic Symptoms in Outpatients with Psychosomatic Illness

Somatosensory Amplification Scale-Chinese version: psychometric properties and its mediating role in the relationship between alexithymia and somatization

The Somatosensory Amplification Scale (SSAS) was designed to measure individual's tendency to experience visceral and somatic sensations as unusually intense, disturbing and alarming. In this study, we aimed to investigate the reliability and validity of the SSAS in the Chinese general population, as well as the mediating effect of somatosensory amplification in the relationship between alexithymia and somatization. A total of 386 healthy adults were enrolled in this study. Participants completed the Chinese versions of the Somatosensory Amplification Scale (SSAS-C), the somatization subscale of the Symptom Check List 90 (SCL-90 som), the Toronto Alexithymia Scale (TAS-20), and the Short form Health Anxiety Inventory (SHAI). One hundred and thirty-three participants were randomly selected to complete the SSAS-C again two weeks after the initial assessment. The reliability and validity of the SSAS-C were analyzed. Confirmatory factor analysis showed that the one-factor model achieved adequate model fits; one item was deleted due to low factor loading. The revised SSAS-C showed good internal consistency and test-retest reliability. The SSAS-C scores correlated positively with the scores of SCL-90 som, TAS-20 and the SHAI, showing good convergent validity. In addition, somatosensory amplification mediated the association between alexithymia and somatization. The Chinese version of SSAS has acceptable reliability and validity for the general population. In addition, alexithymia may increase somatization through higher somatosensory amplification.

Alexithymia is associated with insomnia in Chinese patients with schizophrenia

Background

Sleep disorders are prevalent among patients with schizophrenia and are associated with several negative consequences. Although, researchers have recently suggested that sleep disorders have a close correlation with alexithymia, and schizophrenia also has a strong correlation with alexithymia, there have been few studies on the relationships between schizophrenia, sleep disorders and alexithymia. Therefore, this study aimed to explore the relationships between psychiatric symptoms, alexithymia and sleep problems in patients with schizophrenia so as to provide a reference for the clinical treatment of this comorbidity.

Methods

In total, 977 patients with schizophrenia were recruited for this study. The Insomnia Severity Index (ISI) was used to assess sleep disorders, and the Positive and Negative Syndrome Scale (PANSS), Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Toronto Alexithymia Scale (TAS) were used to evaluate clinical symptoms, cognitive functions and the ability to express emotion, respectively.

Results

The results indicated that the PANSS subscales (G-subscore) and TAS group were risk factors for insomnia in schizophrenia patients (all p < 0.05). The mediation model showed the standardized path coefficients from schizophrenia to alexithymia (β = 0.104, p < 0.001) and from alexithymia to insomnia (β = 0.038, p < 0.001) were statistically significant.

Conclusion

The results of this study indicated that alexithymia is associated with sleep disturbance in patients with schizophrenia. These findings may provide a new avenue for the treatment of schizophrenia patients with sleep disorders.

Alexithymia, Burnout, and Hopelessness in a Large Sample of Healthcare Workers during the Third Wave of COVID-19 in Italy

In the present study, we aimed to assess the frequency of and the relationships between alexithymia, burnout, and hopelessness in a large sample of healthcare workers (HCWs) during the third wave of COVID-19 in Italy. Alexithymia was evaluated by the Italian version of the 20-item Toronto Alexithymia Scale (TAS-20) and its subscales Difficulty in Identifying Feelings (DIF), Difficulty in Describing Feelings (DDF), and Externally Oriented Thinking (EOT), burnout was measured with the scales emotional exhaustion (EE), depersonalisation (DP), and personal accomplishment (PA) of the Maslach Burnout Test (MBI), hopelessness was measured using the Beck Hopelessness Scale (BHS), and irritability (IRR), depression (DEP), and anxiety (ANX) were evaluated with the Italian version of the Irritability' Depression' Anxiety Scale (IDA). This cross-sectional study recruited a sample of 1445 HCWs from a large urban healthcare facility in Italy from 1 May to 31 June 2021. The comparison between individuals that were positive (n = 214, 14.8%) or not for alexithymia (n = 1231, 85.2%), controlling for age, gender, and working seniority, revealed that positive subjects showed higher scores on BHS, EE, DP IRR, DEP, ANX, DIF, DDF, and EOT and lower on PA than the not positive ones (p < 0.001). In the linear regression model, higher working seniority as well as higher EE, IRR, DEP, ANX, and DDF scores and lower PA were associated with higher hopelessness. In conclusion, increased hopelessness was associated with higher burnout and alexithymia. Comprehensive strategies should be implemented to support HCWs' mental health and mitigate the negative consequences of alexithymia, burnout, and hopelessness.

Alexithymia and asthma: a systematic review

Growing evidence from scientific research elucidates the important role of alexithymia in chronic immune diseases. This Review aims to explore the presence of alexithymia in patients affected by asthma and clarify its associations with other involved psychological and physical factors. In January 2023, according to PRISMA guidelines, a systematic search using PubMed and Scopus was conducted. Twenty-six studies were eligible based on inclusion criteria. Alexithymia was significantly present in asthma patients, with most studies reporting a higher prevalence (from 9 to 62.8%) than in control groups (approximately 10%). The coexistence of asthma and alexithymia was associated with a worse quality of life, psychiatric comorbidity, poor symptom control, and difficulty in recognizing exacerbations of the disease. These results suggest that alexithymia can negatively impact the management of asthma. For this reason, we recommend an accuracy assessment in clinical settings and the implementation of psychological interventions to promote the emotional and physical wellbeing of asthmatic patients.

The relationship between alexithymia, depression, anxiety, and stress in elderly with multiple chronic conditions in China: a network analysis

Objective

This study aimed to construct a network structure to investigate the connections between alexithymia, depression, anxiety, and stress in Chinese older adults with multiple chronic conditions (MCC), identifying core and bridge symptoms, and comparing the network structure across different levels of alexithymia.

Methods

This study used a cross-sectional survey design and convenience sampling to recruit participants from six cities in Jiangsu Province. The study assessed the levels of alexithymia, depression, anxiety, and stress in older adults with MCC using the Toronto Alexithymia Scale (TAS-20) and the Depression Anxiety and Stress Scale-21 (DASS-21). Network analysis was performed using R language to identify core and bridge symptoms in the network and compare the network structure across different levels of alexithymia.

Results

A total of 662 participants were included in the analysis, including 395 men and 267 women. The mean age was 70.37 ± 6.92 years. The finding revealed that the "Difficulty Identifying Feelings" (DIF) node had the highest strength centrality (strength = 2.49) and predictability (rp = 0.76) in the network. The next highest strength centrality was observed for "Meaningless" (strength = 1.50), "Agitated" (strength = 1.47), "Scared" (strength = 1.42), and "No look forward" (strength = 0.75). They were identified as core symptoms. The bridge strength analysis identified "Panic," "Scared," "No wind down," "No initiative," and "No positive" as the bridge symptoms. There were notable differences in the overall network structure and specific connections between the groups with and without alexithymia (p < 0.05).

Conclusion

"DIF" is a core node in the network of older adults with MCC, indicating its significance as a potential target for psychological interventions in clinical practice. Preventing and mitigating bridge symptoms such as "panic," "Scared," "No wind down," "No initiative," and "No positive" can effectively impede the spread of symptom activation, thereby interrupting or severing the connections among comorbidities in older adults. Additionally, compared to non-alexithymia individuals, the psychological issues of older adults with alexithymia require prioritized intervention from healthcare professionals.

Do alexithymia and negative affect predict poor sleep quality? The moderating role of interoceptive sensibility

OBJECTIVES

Emotion-related hyperarousal is an important core pathology of poor sleep. Studies investigating the interplay of alexithymia and affective experiences in determining sleep quality have yielded mixed results. To disentangle the inconsistency, this study examined the concurrent predictive power of alexithymia, and negative and positive affect, while incorporating interoceptive sensibility (IS) as a possible moderator.

METHODS

A sample of 224 (70.10% were female) participants completed the Toronto Alexithymia Scale, Positive and Negative Affect Schedule, Pittsburgh Sleep Quality Index, Multidimensional Assessment of Interoceptive Awareness (MAIA), and Marlowe-Crowne Social Desirability Scale (for controlling response bias) using paper and pencil. A two-stage cluster analysis of the MAIA was used to capture IS characteristics. Stepwise regression was conducted separately for each IS cluster.

RESULTS

A three-group structure for IS characteristics was found. Higher alexithymia was predictive of poor sleep quality in the low IS group, while higher negative affect predicted poor sleep quality in the moderate and high IS groups. Additionally, alexithymia and positive affect were significantly different in the three IS groups, while negative affect and sleep quality were not.

CONCLUSIONS

Emotion and cognitive arousal may impact sleep quality differently in individuals with different levels of internal focusing ability, depending on physiological versus emotional self-conceptualization. The implications on pathological research, clinical intervention, study limitations and future directions are discussed.

Emotional intelligence, alexithymia and suicidal ideation among depressive patients

BACKGROUND

Depression is more than just sentiment sad or passing a rough patch. It is a serious psychological wellbeing disorder that needs curative care and maintenance. Emotional Intelligence (EI) is a comprehensive personality construct denoting the capability to perceive and control affects within the self. Alexithymia is another personality construct that refers to the difficulty of recognizing and expressing feelings, with an outside oriented thinking style. Suicidal ideation is defined as thinking of appealing in conduct intentional to end one's life.

AIM

The current study aimed to examine the relationship between emotional intelligence, alexithymia and suicidal ideation among depressive patients.

DESIGN

A descriptive correlation design was utilized.

SETTING

This study was conducted at the Psychiatric Outpatient Clinic in El Ahrar Hospital, Alsharkia Governorate, Egypt.

SUBJECTS

A purposeful sample of 65 depressed patients was recruited for this study.

TOOLS

Data were collected by using four tools: Socio-demographic Data Sheet, Emotional Intelligence Scales, Toronto Alexithymia Scale (TAS-20) and Suicidal Ideation Scale.

RESULTS

The majority of depressed patients were having alexithymia and having low emotional intelligence. Emotional intelligence was statistically significantly negatively correlated with alexithymia and suicidal ideation. Nevertheless, alexithymia was statistically significantly positively correlated with suicidal ideation. It was statistically significantly positively predictor of suicidal ideation and alexithymia, while it was statistically significantly negatively predictor of suicidal ideation and emotional intelligence.

CONCLUSION

Lower emotional intelligence led to higher suicidal ideation in depressive patients. Increasing alexithymia in patients with depressive disorders caused an increase in their suicidal ideation. Therefore, it is recommended implementing a training program such as mindfulness and emotional intelligence skills for patients to enhance their emotional intelligence.

Differences of medically unexplained symptoms among patients of different ages and sexes in the psychological clinic of a general hospital and the influencing factors of MUS: A cross-sectional study

OBJECTIVE

To analyse differences in sex, age, depression, insomnia, psychological stress, resilience, and perceived social support among patients with medically unexplained symptoms (MUS) in a psychological clinic of a general hospital, and to explore the influencing factors of MUS.

METHODS

This is a cross-sectional study. Seven hundred forty-six first-time patients were assessed with the integrated psychosomatic comprehensive evaluation system (IPS) to evaluate their MUS, depression, insomnia, psychological stress, resilience, and perceived social support. The psychological characteristics were compared with regard to sex and age group (<25 years, low age group; 26-44 years, middle age group; >45 years, high age group). The relationships between age and MUS were explored, and how psychological stress affects MUS was analyzed using the mediator effect model.

RESULTS

Different age groups had significant differences in sex, MUS, depression, psychological stress, resilience, and perceived social support. In further pairwise comparison, no significant difference existed in depression, psychological stress, resilience and perceived social support in the middle and low age groups, depression and psychological stress were higher than those in the high age group, resilience and perceived social support were lower than those of the high age group. MUS were higher in the middle age group than in the low age group. No significant difference existed between the two groups and the high age group. Age, severity of MUS, and perceived social support were significantly different between the sexes. Differences in MUS between men and women in different age groups were analyzed using two-factor analysis of variance. It revealed no interaction between sex and different age groups on MUS. The main effect analysis showed that the effects of different age groups on MUS were statistically significant. Based on pairwise comparative analysis, the MUS score in the low age group was lower than that in the middle age group. To clarify a nonlinear relationship between age and MUS, threshold effect analysis was conducted. The results indicated that the piecewise linear regression model could better depict the relationship between age and MUS. The inflection point was at the age of 60 years. Before the age of 60 years, MUS increased with age. No significant correlation existed between age and MUS after the age of 60 years. To understand the influencing factors of MUS, the intermediary effect model was analyzed using MUS as the dependent variable, psychological stress as the independent variable, resilience as mediator variable M1, perceived social support as mediator variable M2, and depression as mediator variable M3. Resilience, perceived social support, and depression had significant mediator effects on the effects of psychological stress on MUS with a total indirect effect of 69.81%.

CONCLUSION

The middle age group had greater MUS than the low age group. Before the age of 60 years, MUS increased with increasing age. Women had more severe MUS than men. Resilience, perceived social support, and depression had significant mediating effects on the effects of perceived stress on MUS. These findings suggest that clinicians should make more comprehensive and detailed evaluations and timely intervention for middle-aged and female patients. Improving psychological resilience and social support can reduce the impact of psychological stress on MUS. Therefore, psychotherapy and multidisciplinary comprehensive treatment are very important for patients is very important for patients.

Assessing Differential Effects of Somatic Amplification to Positive Affect in Midlife and Late Adulthood-A Regression Mixture Approach

This study aims to provide an empirical demonstration of a novel method, regression mixture model, by examining differential effects of somatic amplification to positive affect and identifying the predictors that contribute to the differential effects. Data derived from the second wave of Midlife in the United States. The analytic sample consisted of 1,766 adults aged from 33 to 84 years. Regression mixture models were fitted using Mplus 7.4, and a two-step model-building approach was adopted. Three latent groups were identified consisting of a maladaptive (32.1%), a vulnerable (62.5%), and a resilient (5.4%) group. Six covariates (i.e., age, education level, positive relations with others, purpose in life, depressive symptoms, and physical health) significantly predicted the latent class membership in the regression mixture model. The study demonstrated the regression mixture model to be a flexible and efficient statistical tool in assessing individual differences in response to adversity and identifying resilience factors, which contributes to aging research.

Comparison of brain activity within the sensorimotor network between sports players and patients with somatic symptom disorder

OBJECTIVE

We aimed to identify differences in brain functional connectivity (FC) and characteristics of body sensation between sports players and patients with somatic symptom disorder (SSD), in order to investigate the neurobiological basis of SSD.

METHODS

Thirty-five sports players (SPORTS group), 36 patients with SSD (SOM group), and 33 healthy control participants (HC group) underwent resting-state functional magnetic resonance imaging. We used a seed-based FC analysis.

RESULTS

Both groups showed increased brain activity in the left precuneus. The level of body intelligence in the SPORTS group and the level of somatosensory amplification in the SOM group were positively correlated with brain activity in the left precuneus. The SPORTS group showed increased FC between the left precuneus and the right/left insula compared to the HC group. The SOM group showed increased FC between the left precuneus and the right parahippocampal gyrus compared to the HC group. The SPORTS group showed increased FC between the left precuneus and left posterior cingulate gyrus compared to the SOM group.

CONCLUSION

Increased FC between the precuneus within the default mode network (DMN) and the insula connected to the sensorimotor network in sports players may be related to better somatosensory functions. In contrast, increased FC between the precuneus of the DMN and the parahippocampal gyrus of the affective network in SSD may be associated with dysfunctional processing and misconception of information. Future studies should examine whether treatments for improving affective processing normalize the affective network, and if this is correlated with somatic symptom improvement.

The relationships between cognitive control and psychological symptoms in patients with somatic symptom disorder: a pilot longitudinal study

INTRODUCTION

The present study explored how neurocognitive function correlated with the clinical symptoms of somatic symptom disorder (SSD) by evaluating changes in cognitive abilities according to differences in relevant factors.

METHODS

A total of 44 patients with SSD and 30 healthy controls completed tests assessing various neurocognitive domains, including verbal memory, psychomotor speed, executive function, working memory, and sustained and divided attention. They also completed questionnaires for psychological assessment. The same tests and questionnaires were completed by 26 SSD patients 6 months later.

RESULTS

The SSD patients had significantly lower scores on the attentional and verbal memory tests than did the healthy controls. Performance on the attentional test was significantly associated with the level of somatic symptoms and anxiety. The follow-up assessment results of the SSD patients revealed improved performance on the verbal learning and fluency tests as well as improvements in somatic symptoms, anxiety, and depression. It was also observed that changes in verbal learning and attentional functions were significantly associated with improvements in somatic symptoms.

CONCLUSIONS

The present study suggests that neurocognitive dysfunctions are subtle and not specific to SSD, but certain cognitive functions may be related to the clinical symptoms and improvements of patients with SSD.

The relationship of cortical activity induced by pain stimulation with clinical and cognitive features of somatic symptom disorder: A controlled functional near infrared spectroscopy study

OBJECTIVE

The neurobiological correlates of Somatic Symptom Disorder (SSD) introduced in the DSM-5 has been the focus of a limited investigation. We aimed to examine the cortical response to painful stimuli and its relationship to symptom severity as well as cognitive and psychological characteristics in proposed models of somatoform disorders.

METHODS

We measured hemodynamic responses by 52-channel functional near-infrared spectroscopy. We compared the cortical response to painful stimuli in index patients with SSD (N = 21) versus age, and gender matched healthy control subjects (N = 21). We used brush stimulation as the control condition. We analyzed the relationship of cortical activity with SSD symptom severity as well as somatosensory amplification (SSA), alexithymia, dysfunctional illness behaviour, worry, and neuroticism.

RESULTS

Patients with SSD had higher somatic symptom severity, SSA, alexithymia, neuroticism, illness-related worry, and behaviour. Somatic symptom severity was predicted by a model including SSA and subjective feeling of pain in the index patients. Activity in the left-angular and right-middle temporal gyri was higher in the SSD subjects than the controls during pain stimulation. Positive correlations were detected between mean pain threshold levels and left middle occipital gyrus activity, as well as between SSA-scores and right-angular gyrus activity during pain condition in the index patients with SSD.

CONCLUSION

We present the first evidence that representation of pain in terms of cortical activity is different in subjects with SSD than healthy controls. SSA has functional neuroanatomic correlates and predicts symptom severity in SSD and therefore is involved as a valid intermediate phenotype in SSD pathophysiology.

A retrospective observational study comparing somatosensory amplification in fibromyalgia, chronic pain, psychiatric disorders and healthy subjects

OBJECTIVES

Somatosensory amplification (SA) has been described as an important feature of somatoform disorders, and an "amplifying somatic style" has been reported as a negative connotation of body perception. As widespread pain (WSP) in fibromyalgia (FM) is due to a central sensitization (CS) rather than organic alterations, there has been discussion as to whether FM is equivalent to or distinct from somatization disorder (SD). Assuming SD and FM are two distinct entities, an increase in somatic amplification should be expected only in subjects who have SD, regardless of the type of pain they experience. Purpose of the study was to explore the magnitude of SA in FM, and whether this depends on the association with SD.

METHODS

FM (n=159) other forms of chronic pain (OCP, n=582), psychiatric (Psy, n=53) and healthy (H, n=55) subjects were investigated using the Somatosensory Amplification Scale (SSAS), Illness Behavior Questionnaire, (IBQ), Italian Pain Questionnaire (IPQ), and Cold Pressor Test (CPT) in a retrospective observational study.

RESULTS

FM subjects displayed higher SSAS scores than the other groups. High SSAS score was associated with FM (OR=8.39; 95%CI: 5.43-12.46) but not OCP. Although FM has the highest prevalence of SD (x²=14.07; p=.007), high SSAS scores were associated with SD in OCP but not in FM.

CONCLUSIONS

Unlike in OCP, in FM high SSAS scores were independent of the presence of SD. From a biopsychosocial perspective, SSAS may be a factor associated with the onset of FM.

A comparison of patients with somatic symptom disorder attending psychiatric services and those unwilling to attend psychiatric services

The present study aimed to compare the symptom profile, psychological correlates, public stigma, quality of life and disability of patients with somatic symptom disorder attending the psychiatric outpatient services and those who refuse to attend the psychiatry outpatient services. For this, patients were recruited from both Psychiatry outpatient services (N = 62) and Rheumatology outpatient services (N = 41). Participants were assessed on Screening for Somatoform Disorders Instrument, Beck's Depression Inventory, Somatosensory Amplification Scale, Whitley Index, Twenty-item Toronto Alexithymia Scale-Hindi version, Community Attitudes toward the Mentally Ill Scale, World Health Organization-Quality of Life Scale-BREF version (Hindi) and Indian Disability Evaluation and Assessment Scale. Both the groups were comparable on socio-demography and symptom profile. Compared to the patients attending the psychiatry outpatient services, patients attending the rheumatology outpatient services had higher level of somatosensory amplification, hypochondriasis, alexithymia (in the subscales of difficulty in identifying and describing feelings), higher stigmatizing attitude towards mental illness, poorer quality of life and higher disability. To conclude, present study suggests that, patients of somatic symptom disorder, who refuse to attend the psychiatry outpatient services differ from those attending the psychiatry outpatient services in terms of somatosensory amplification, alexithymia, hypochondriasis, public stigma held towards mental illnesses, disability and quality of life. There is a need to develop a treatment model to address these issues in the medical setting to improve the outcome of patients with somatic symptom disorders attending the medical outpatient setting.

Mentalizing self and others: A controlled study investigating the relationship between alexithymia and theory of mind in major depressive disorder

BACKGROUND

Theory of mind (ToM) and alexithymia have been reported to relate with depression in recent studies. However, data regarding the role of alexithymia and ToM in depression remain uncertain.

AIM

The aim of the current study was to determine the levels of alexithymia and ToM abilities as well as their relationship with each other and clinical features in major depressive disorder (MDD).

MATERIALS AND METHODS

Patients diagnosed with MDD and healthy controls were undergone sociodemographic data, Beck Depression Inventory, Beck Anxiety Inventory, Toronto Alexithymia Scale (TAS-20), and reading the mind in the eyes test (RMET) to determine the depression, anxiety, alexithymia, and ToM abilities.

RESULTS

Depression, anxiety, and alexithymia levels were higher, while ToM abilities were found to be decreased in MDD patients relative to controls. A positive correlation was observed between depression levels and alexithymia levels in terms of difficulty in identifying feelings subscale and total scores of TAS-20 (P = 0.006, P = 0.036, respectively), while a positive correlation was also observed between anxiety levels and alexithymia levels in terms of difficulty in describing feelings subscale scores of TAS-20 (P = 0.02) in depressed group. No correlation was found between depression, anxiety levels, and RMET accuracy scores.

CONCLUSION

Our results suggest alexithymia and impaired ToM abilities might be prominent but prone to be distinct clinical constructs in MDD patients.

Impact of symptom focusing and somatosensory amplification on persistent physical symptoms: A three-year follow-up study

OBJECTIVE

The somatosensory amplification theory considers symptom focusing and somatosensory amplification as important perpetuating factors of persistent physical symptoms. We investigated whether symptom focusing and somatosensory amplification were associated with symptom severity and mental and physical functioning over a three-year period in patients with persistent physical symptoms (PPS).

METHODS

Baseline, 6-, 12-, 24- and 36-months follow-up data from the PROSPECTS study, a prospective cohort consisting of 325 patients with PPS, were used. We applied longitudinal mixed model analyses to investigate if symptom focusing (CBRQ Symptom Focusing Subscale) and somatosensory amplification (Somatosensory Amplification Scale) at baseline were associated with symptom severity (PHQ-15), mental and physical functioning (RAND-36 MCS and PCS) over three years, using all measurements.

RESULTS

Symptom focusing was associated with increased symptom severity and lower mental and physical functioning over time. Somatosensory amplification at baseline was associated with increased symptom severity and lower mental and physical functioning over time. Effect sizes were small. Associations with baseline symptom focusing decreased over time, associations with baseline somatosensory amplification were more stable. There was no interaction effect of both constructs, but they partly overlapped.

CONCLUSION

This is the first study to show that over an extended period, symptom focusing and somatosensory amplification are associated with symptom severity and lower mental and physical functioning in patients with PPS. These results support the impact of both symptom focusing and somatosensory amplification on the perpetuation of symptoms and lowered mental and physical functioning in individuals with PPS.

Insula Activity to Visceral Stimulation and Endocrine Stress Responses as Associated With Alexithymia in Patients With Irritable Bowel Syndrome

OBJECTIVE

Few studies have investigated associations between alexithymia and physiological mechanisms in psychosomatic diseases. We examined associations between alexithymia and 1) perception and brain processing of visceral stimulation and 2) the endocrine responses to corticotrophin-releasing hormone (CRH) in healthy individuals and patients with irritable bowel syndrome (IBS).

METHODS

The study included 29 patients with IBS and 35 age- and sex-matched healthy controls (HCs). Alexithymia was measured using the 20-item Toronto Alexithymia Scale (TAS-20). Brain responses to rectal distention and its anticipation were measured by functional magnetic resonance imaging and analyzed at a voxel-level threshold of puncorrected < .001 combined with a cluster-level threshold of pFWE-corrected < .05. On a different day, plasma adrenocorticotropic hormone and cortisol responses after intravenous CRH administration were measured.

RESULTS

TAS-20 scores did not differ significantly between patients with IBS and HCs (p = .18). TAS-20 scores correlated positively with the individual rectal discomfort thresholds (βrobust = 0.49, p = .03) and negatively with the rating of fear before rectal distention (βrobust = -1.63, p = .04) in patients with IBS but not in HCs. Brain responses to rectal distention in the right insula and other brain regions were positively associated with TAS-20 scores to a greater extent in patients with IBS than in HCs. Individuals with higher TAS-20 scores (both patients with IBS and HCs) demonstrated stronger adrenocorticotropic hormone responses to CRH administration (F(4,224) = 3.54, p = .008).

CONCLUSION

Higher alexithymia scores are associated with stronger physiological responses, but lower anticipatory fear ratings and higher discomfort thresholds, particularly in patients with IBS.