Psychobiological differences between depression and somatization

Frontal alpha asymmetry is associated with chronic stress and depression, but not with somatoform disorders

Cardinal characteristics of somatoform disorders (SFDs) are worry of illness, and impaired affective processing. We used relative frontal alpha asymmetry (FAA), a method to measure functional lateralization of affective processing, to investigate psychobiological correlates of SFDs. With alpha activity being inversely related to cortical network activity, relative FAA refers to alpha activity on the right frontal lobe minus alpha activity on the left frontal lobe. Less relative left frontal activity, reflected by negative FAA scores, is associated with lower positive and greater negative affectivity, such as observed in depression. Due to its negative affective component (illness anxiety), we expected to find less relative left frontal activity pattern in SFDs, and positive associations with self-reported chronic stress and depression symptoms. We recorded resting-state EEG activity with 64 electrodes, placed in a 10-10 system in 26 patients with a primary SFD, 23 patients with a major depressive disorder and 25 healthy control participants. The groups did not differ in FAA. Nevertheless, across all participants, less relative left frontal activity was associated with chronic stress and depression symptoms. We concluded that FAA may not serve as an indicator of SFDs. As the relationship of FAA and depressive symptoms was fully mediated by chronic stress, future studies have to clarify whether the association between FAA and chronic stress may represent a shared underlying factor for the manifestation of mental health complaints, such as depression.

Adherence to Masculinity Norms and Depression Symptoms Among Israeli Men: The Moderating Role of Psychological Flexibility

Being a man has been recognized as a salient risk factor for suicide. Adopting uncompromised masculine perceptions (i.e., conforming to the masculine gender role norms) may restrict emotional expressiveness in men, which, in turn, may contribute to depression and somatization symptoms. We examined the moderating role of psychological flexibility and alexithymia in the relationship of masculinity with depression and somatization symptoms. A sample of 119 men completed measures of masculinity, alexithymia (difficulty identifying and delivering subjective feelings), psychological flexibility, depression, and somatization symptoms in a cross-sectional design study. Psychological flexibility levels moderated the relationship between masculinity and depression symptoms: Masculinity contributed as positively associated with depression symptoms when psychological flexibility was low, but no such association was found at moderate or high levels of psychological flexibility. As a cognitive factor promoting adaptive emotional regulation, psychological flexibility might reduce depression symptoms among inflexible masculine men. Clinical implications relate to diagnosing at-risk subgroups and their treatment.

A head-to-head comparison of eight unique personality systems in predicting somatization phenomenon

BACKGROUND

If somatization is an independent personality trait, it is not clear whether it is specific to the temperament or maladaptive spectrum of personality. We aimed at the head-to-head comparison of temperament and maladaptive systems and spectra of personality to predict both somatization and somatic symptom and related disorders (SSRD).

METHODS

The samples included 257 cases with SSRD (70.8% female) and 1007 non-SSRD (64.3% female) from Western Iran. The Personality Inventory for DSM-5 (PID-5), Personality Diagnostic Questionnaire-4 (PDQ-4), Temperament and Character Inventory (TCI), Temperament Evaluation of Memphis, Pisa, Paris, and San Diego-Autoquestionnaire (TEMPS-A), Affective and Emotional Composite Temperament Scale (AFECTS), and Positive Affect and Negative Affect Model (PANAS) was used to data collection. A somatization factor plus temperament and maladaptive spectra of personality were extracted using exploratory factor analysis. Several hierarchical linear and logistic regressions were used to test the predictive systems and spectra.

RESULTS

All personality systems jointly predict both somatization and SSRD with a slightly higher contribution for temperament systems. When the temperament and maladaptive spectra were compared, both spectra above each other significantly predicted both somatization (R2 = .407 versus .263) and SSRD (R2 = .280 versus .211). The temperament spectrum explained more variance beyond the maladaptive spectrum when predicting both the somatization factor (change in R2 = .156 versus .012) and SSRD (change in R2 = .079 versus .010).

CONCLUSION

All temperament and maladaptive frameworks of personality are complementary to predicting both somatization and SSRD. However, the somatization is more related to the temperament than the maladaptive spectrum of personality.

The relationship between self-reported chronic stress, physiological stress axis dysregulation and medically-unexplained symptoms

The positive feedback model of medically-unexplained symptoms posits that chronic stress affects the activity of the physiological stress axes, which in turn generates medically-unexplained symptoms. As a first step to empirically test its model assumptions, we investigated potential associations between chronic stress, physiological stress axis activity and medically-unexplained in a cross-sectional study. One hundred-ninety-nine healthy individuals provided self-reports on chronic stress and medically-unexplained symptoms, resting heart rate/variability (HR/HRV; e.g., root mean square of successive differences/RMSSD, low frequency/LF power), cortisol awakening response (CAR) and diurnal cortisol. Significant positive contributors to medically-unexplained symptoms were the chronic stress scales 'lack of social appreciation' and 'chronic worries', as well as CAR and LF HRV; diurnal cortisol was a negative contributor. Mediation analyses showed that the impact of neural indicators associated with physiological stress axis activity (HR/HRV) related to medically-unexplained symptoms, which was mediated by chronic stress, whereas the mediation effect as suggested by the positive feedback model was not significant. These cross-sectional findings do not support the positive feedback model. Longitudinal studies are required to conclude about potential mechanistic and causal relationships in the model. Nevertheless, our mediation analyses give first indication that the constitution of physiological stress axes may play a major role in how stressors are perceived and which kind of health-consequences (e.g., medically-unexplained symptoms) this may have.

Somatic symptom distress and ICD-11 prolonged grief in a large intercultural sample

Background: Grief is a multi-faceted experience including emotional, social, and physical reactions. Research in ICD-11 prolonged grief disorder (PGD) in different cultural contexts has revealed different or potentially missing grief symptoms that may be relevant.Objective: This study thus aimed to explore the prevalence of somatic symptom distress and its associations with grief and negative affect in a culturally diverse sample of bereaved individuals with symptoms of PGD.Methods: Based on cross-sectional survey data from the Measurement and Assessment of Grief (MAGIC) project, this study included 1337 participants (mean age 23.79 yrs, 76.1% female) from three regions (USA: 62.3%, Turkey/Iran: 24.2%, Cyprus/Greece: 13.5%), who experienced a loss of a significant other. Associations between somatic symptom distress (Somatic Symptom Scale, SSS-8), symptoms of PGD (International Prolonged Grief Disorder Scale, IPGDS-33), anxiety (Generalized Anxiety Disorder Questionnaire, GAD-7), depression (Patient Health Questionnaire, PHQ-9) as well as demographic and loss related characteristics were investigated. Three hundred and thirteen participants (23.4%) scored above the proposed cut-off for clinically severe PGD.Results: 'High' or 'very high' levels of somatic symptom distress were more frequent in a possible PGD group (58.2%), than in a non-PGD group (22.4%), p < .001, as divided per cut-off in the IPGDS. In a multiple regression analysis, PGD symptoms were significantly but weakly associated with somatic symptom distress (β = 0.08, p < .001) beyond demographics, loss-related variables, and negative affect. Negative affect (anxiety and depression) mediated the relationship of PGD symptoms with somatic symptom distress and the indirect effect explained 58% of the variance.Conclusions: High levels of somatic symptom distress can be observed in a substantial proportion of bereaved across cultures. Our findings suggest that PGD is related to somatic symptom distress partly and indirectly through facets of negative affect.

Chronic Pain and Depression are Increased in Outpatient Adults with Somatic Symptoms from Secondary Health Care Services

BACKGROUND

Somatic symptom disorder is described as excessive thoughts, feelings, or behaviors related to physical symptoms. The presence of somatic symptoms has been associated with depression, alexithymia, and the presence of chronic pain. Individuals with somatic symptom disorder are frequent attenders of primary health care services.

AIM

We focused on investigating if the presence of psychological symptoms, alexithymia, or pain could be risk factors for somatic symptoms in a secondary health care service.

METHODS

A cross-sectional and observational study. A total of 136 Mexican individuals who regularly attend a secondary health care service were recruited. The Visual Analogue Scale for Pain Assessment, the Symptom Checklist 90, and the Patient Health Questionnaire-15 were applied.

RESULTS

Of all the participants, 45.2% showed somatic symptoms. We observed that these individuals more frequently presented with complaints of pain (χ² = 18.4, p < .001), as well as more severe (t = -4.6, p < .001), and prolonged (χ² = 4.9, p = 0.02). They also exhibited higher severity in all psychological dimensions assessed (p < .001). Finally, cardiovascular disease (t = 2.52, p = .01), pain intensity (t = 2.94, p = .005), and SCL-90 depression (t = 7.58, p < .001) were associated with somatic symptoms.

CONCLUSIONS

In this study, we observed a high frequency of somatic symptoms in outpatients attending secondary health care services. They may be accompanied by comorbid cardiovascular conditions, higher pain intensity, and other mental health-related symptoms, which may aggravate the general clinical picture presented by the patient seeking health care. The presence and severity of somatization should be taken into consideration in the first and second level health care services for an early mental state evaluation and treatment of these outpatients to have a better clinical assessment and health outcome.

Profiles of early family environments and the growth of executive function: Maternal sensitivity as a protective factor

We identified family risk profiles at 6 months using socioeconomic status (SES) and maternal mental health indicators with data from the Family Life Project (N = 1,292). We related profiles to executive function (EF) at 36 months (intercept) and growth in EF between 36 and 60 months. Latent profile analysis revealed five distinct profiles, characterized by different combinations of SES and maternal mental health symptoms. Maternal sensitivity predicted faster growth in EF among children in the profile characterized by deep poverty and the absence of maternal mental health symptoms. Maternal sensitivity also predicted higher EF intercept but slower EF growth among children in the profile characterized by deep poverty and maternal mental health symptoms, and children in the near poor (low SES), mentally healthy profile. Maternal sensitivity also predicted higher EF intercept but had no effect on growth in EF in the near poor, mentally distressed profile. In contrast, maternal sensitivity did not predict the intercept or growth of EF in the privileged SES/mentally healthy profile. Our findings using a person-centered approach provide a more nuanced understanding of the role of maternal sensitivity in the growth of EF, such that maternal sensitivity may differentially affect the growth of EF in various contexts.

Recent developments on psychological factors in medically unexplained symptoms and somatoform disorders

Somatic symptoms which are not fully explained by a medical condition (medically unexplained symptoms) have a high relevance for the public health. They are very common both in the general population and in patients in health care, and may develop into chronic impairing conditions such as somatoform disorders. In recent years, the relevance of specific negative psychological factors for the diagnosis and the stability of somatoform disorders and for the impairment by medically unexplained symptoms gained more and more attention. This resulted-among others- in core changes in the diagnostic classification criteria of somatoform disorders. Against this background, the present "Perspective" will outline recent developments and findings in the area of medically unexplained somatic symptoms and somatoform disorders. Moreover, it will lay a special focus on evidence on specific negative psychological factors that may influence the course of unexplained somatic symptoms and disorders and the impairment caused by these symptoms.

Involvement of Anti-Inflammatory and Stress Oxidative Markers in the Antidepressant-like Activity of Aloysia citriodora and Verbascoside on Mice with Bacterial Lipopolysaccharide- (LPS-) Induced Depression

Aloysia citriodora Palau is popularly used to treat nervous disorders. Experimental evidence has indicated that verbascoside (VBS) isolated from A. citriodora has pharmacological potential. In this study, we evaluated the antidepressant-like effects of a hydroalcoholic extract of A. citriodora (HEAc) and VBS against lipopolysaccharide- (LPS-) induced depressive-like behavior in mice. In the pretreatment protocol (performed to evaluate the preventive potential), mice were pretreated with HEAc (3, 30, or 300 mg/kg) or VBS (30 mg/kg) before the administration of LPS. In the posttreatment protocol (performed to evaluate the therapeutic potential), mice were initially administered LPS and were subsequently given HEAc (3, 30, or 300 mg/kg) or VBS (30 mg/kg). In both treatments, the mice were submitted to an open-field test and tail suspension test (TST) at 6 and 24 h after LPS administration. The posttreatment evaluation revealed that HEAc (30 or 300 mg/kg) and VBS produced an antidepressant-like effect, as indicated by a reduction in the time spent with no movement in the TST. Moreover, HEAc (30 or 300 mg/kg) was found to reduce interleukin-6 (IL-6) levels and N-acetyl-glycosaminidase activity in the hippocampus, increase glutathione (GSH) levels in the hippocampus and cortex, and enhance IL-10 in the cortex and, at a dose of 300 mg/kg, reduced myeloperoxidase activity in the cortex. Contrastingly, no comparable effects were detected in mice subjected to the pretreatment protocol. Administration of VBS similarly reduced the levels of IL-6 in the hippocampus and increased GSH levels in the cortex. Our observations indicate that both HEAc and VBS show promising antidepressant-like potential, which could be attributed to their beneficial effects in reducing neuroinflammatory processes and antioxidant effects in the central nervous system.

Psychosomatic syndromes are associated with IL-6 pro-inflammatory cytokine in heart failure patients

Psychosomatic syndromes have emerged as an important source of comorbidity in cardiac patients and have been associated with increased risk for adverse outcomes in patients with heart failure (HF). Understanding of the mechanisms underlying this connection is limited, however immune activity represents a possible pathway. While there have been numerous studies connecting immune activity to psychosomatic psychopathology, there is a lack of research on patients with HF. We examined forty-one consecutive outpatients affected by HF. We assessed psychosomatic psychopathology using the Diagnostic Criteria for Psychosomatic Research (DCPR) and the Patient Health Questionnaire-15 (PHQ-15). The Psychosocial Index (PSI) was used for assessing stress and psychosocial dimensions. Depression was evaluated with Beck Depression Inventory-II (BDI-II). Circulating levels of proinflammatory cytokines IL-6 and TNF-alpha were ascertained. Univariate and multivariable regression models were used to test for associations between inflammatory cytokines and psychosomatic psychopathology (i.e., DCPR syndromes, PHQ-15) and psychological dimensions (i.e., BDI-II, PSI). A significant positive correlation was found between IL-6 levels and psychosomatic psychopathology even when controlling for any confounding variables (i.e., Body-mass index (BMI), New York Heart Association (NYHA) class, smoking habits, alcohol consumption, statin use, aspirin use, beta blockers use, age, and gender). In contrast, the associations between TNF-alpha levels were non-significant. These findings can contribute to research in support of a psychoneuroimmune connection between psychosomatic psychopathology and HF. Findings also suggest the possibility that elevated IL-6 levels are more relevant for the pathogenesis of psychosomatic syndromes than for depression in patients with HF.

Psychobiological Mechanisms in Somatic Symptom Disorder and Depressive Disorders: An Ecological Momentary Assessment Approach

OBJECTIVE

Persistent somatic symptoms cause strong impairment in persons with somatic symptom disorder (SSD) and depressive disorders (DDs). Specific negative psychological factors (NPFs), such as catastrophizing, negative affectivity, and behavioral avoidance, are assumed to contribute to this impairment and may maintain symptoms via dysregulations of biological stress systems. We examined the associations between NPF and somatic symptoms in the daily life of women with SSD or DD and investigated the mediating role of psychobiological stress responses.

METHODS

Twenty-nine women with SSD and 29 women with DD participated in an ecological momentary assessment study. For 14 days, intensity of and impairment by somatic symptoms, NPF, and stress-related biological measures (cortisol, alpha-amylase) were assessed five times per day using an electronic device and saliva samples. Multilevel models were conducted.

RESULTS

The greater the number of NPF, the higher the concurrent and time-lagged intensity of and impairment by somatic symptoms in both groups (12.0%-38.6% of variance explained; χ2(12) p < .001 for all models). NPFs were associated with higher cortisol levels in women with DD and with lower levels in women with SSD (interaction NPF by group: B = -0.04, p = .042 for concurrent; B = -0.06, p = .019 for time-lagged). In women with SSD, lower cortisol levels were associated with higher intensity at the next measurement time point (group by cortisol: B = -1.71, p = .020). No mediation effects were found.

CONCLUSIONS

NPFs may be considered as transdiagnostic factors in the development and treatment of impairing somatic symptoms. Our findings will allow the development of new treatment strategies that use ecological momentary intervention approaches focusing on NPF.

The effects of music listening on somatic symptoms and stress markers in the everyday life of women with somatic complaints and depression

Despite a growing body of literature documenting the health-beneficial effects of music, empirical research on the effects of music listening in individuals with psychosomatic disorders is scarce. Using an ambulatory assessment design, we tested whether music listening predicts changes in somatic symptoms, subjective, and biological stress levels, and examined potential mediating processes, in the everyday life of 58 women (M = 27.7 years) with somatic symptom disorder (SSD) and depressive disorders (DEP). Multilevel models revealed that music listening predicted lower subjective stress ratings (p ≤ 0.02) irrespective of mental health condition, which, in turn, predicted lower somatic symptoms (p ≤ 0.03). Moreover, specific music characteristics modulated somatic symptoms (p = 0.01) and autonomic activity (p = 0.03). These findings suggest that music listening might mitigate somatic symptoms predominantly via a reduction in subjective stress in women with SSD and DEP and further inform the development of targeted music interventions applicable in everyday life.

Association of Depressive Symptoms with Rapid Kidney Function Decline in Adults with Normal Kidney Function

BACKGROUND AND OBJECTIVES

The relationship of depressive symptoms with kidney function remains poorly investigated. We aimed to evaluate the prospective association between depressive symptoms and rapid decline in kidney function in Chinese adults with normal kidney function.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A total of 4763 participants with eGFR≥60 ml/min per 1.73 m² at baseline were enrolled from the China Health and Retirement Longitudinal Study. Baseline depressive symptoms were determined using a ten-item Center for Epidemiologic Studies Depression scale with a cutoff score of greater than or equal to ten to define high depressive symptoms. The GFR was estimated by a combination of serum creatinine and cystatin C. The primary outcome was rapid decline in kidney function, defined as an annualized decline in eGFR of ≥5 ml/min per 1.73 m². Secondary outcome was defined as an annualized decline in eGFR of ≥5 ml/min per 1.73 m² and to a level of <60 ml/min per 1.73 m² at the exit visit.

RESULTS

During a median follow-up of 4 years (interquartile range, 3.92-4.00), 260 (6%) participants developed rapid decline in kidney function. Overall, there was a significant positive association between baseline depressive symptoms and rapid decline in kidney function (per five-scores increment; adjusted odds ratio, 1.15; 95% confidence interval, 1.03 to 1.28) after adjustments for major demographic, clinical, or psychosocial covariates. Consistently, compared with participants with low depressive symptoms (total Center for Epidemiologic Studies Depression scale score less than ten), a significantly higher risk of rapid decline in kidney function was found among those with high depressive symptoms (total Center for Epidemiologic Studies Depression scale score greater than or equal to ten; adjusted odds ratio, 1.39; 95% confidence interval, 1.03 to 1.88). Similar results were found for the secondary outcome (per five-scores increment; adjusted odds ratio, 1.26; 95% confidence interval, 1.06 to 1.51).

CONCLUSIONS

High depressive symptoms were significantly associated with a higher risk of rapid kidney function decline among Chinese adults with normal kidney function.

Identifying Predictors of Psychological Distress During COVID-19: A Machine Learning Approach

Scientific understanding about the psychological impact of the COVID-19 global pandemic is in its nascent stage. Prior research suggests that demographic factors, such as gender and age, are associated with greater distress during a global health crisis. Less is known about how emotion regulation impacts levels of distress during a pandemic. The present study aimed to identify predictors of psychological distress during the COVID-19 pandemic. Participants (N = 2,787) provided demographics, history of adverse childhood experiences, current coping strategies (use of implicit and explicit emotion regulation), and current psychological distress. The overall prevalence of clinical levels of anxiety, depression, and post-traumatic stress was higher than the prevalence outside a pandemic and was higher than rates reported among healthcare workers and survivors of severe acute respiratory syndrome. Younger participants (<45 years), women, and non-binary individuals reported higher prevalence of symptoms across all measures of distress. A random forest machine learning algorithm was used to identify the strongest predictors of distress. Regression trees were developed to identify individuals at greater risk for anxiety, depression, and post-traumatic stress. Somatization and less reliance on adaptive defense mechanisms were associated with greater distress. These findings highlight the importance of assessing individuals' physical experiences of psychological distress and emotion regulation strategies to help mental health providers tailor assessments and treatment during a global health crisis.

Interoception, Stress, and Physical Symptoms in Stress-Associated Diseases

Abstract. The brain and peripheral bodily organs continuously exchange information. Exemplary, interoception refers to the processing and perception of ascending information from the body to the brain. Stress responses involve a neurobehavioral cascade, which includes the activation of peripheral organs via neural and endocrine pathways and can thus be seen as an example for descending information on the brain-body axis. Hence, the interaction of interoception and stress represents bi-directional communication on the brain-body axis. The main hypothesis underlying this review is that the dysregulation of brain-body communication represents an important mechanism for the generation of physical symptoms in stress-related disorders. The aims of this review are, therefore, (1) to summarize current knowledge on acute stress effects on different stages of interoceptive signal processing, (2) to discuss possible patterns of abnormal brain-body communication (i.e., alterations in interoception and physiological stress axes activation) in mental disorders and chronic physical conditions, and (3) to consider possible approaches to modify interoception. Due to the regulatory feedback loops underlying brain-body communication, the modification of interoceptive processes (ascending signals) may, in turn, affect physiological stress axes activity (descending signals), and, ultimately, also physical symptoms.

Antidepressant-like effects of solidagenone on mice with bacterial lipopolysaccharide (LPS)-induced depression

BACKGROUND

Considering the pharmacological potential of solidagenone from Solidago chilensis, the present investigation was carried out to evaluate its antidepressant-like effect in mice with bacterial lipopolysaccharide (LPS)-induced depressive like behavior and its mode of action through the measurement of neuroinflammatory and oxidative markers.

MATERIALS AND METHODS

In the prophylactic test, the mice were pretreated with solidagenone (1, 10 or 100 mg/kg, p.o) and after one hour received LPS. In therapeutic test, the mice received LPS and after 5 h were treated with solidagenone (1, 10 or 100 mg/kg, p.o). In both experimental approaches, the animals were submitted to OFT and to the TST after 6 and 24 h of the LPS administration, respectively. One hour after the TST the animals were euthanized, the blood was collected, the cortex was removed and biochemical analyzes were performed for measurement of the inflammatory and oxidative stress markers.

RESULTS

The LPS induced sickness- and depressive-like behaviors and increased the cortical activity of myeloperoxidase (MPO), as well as the IL-6 and TNF amount. Interestingly, the pretreatment with solidagenone at 100 mg/kg avoided the behavioral alterations in OFT. In the mice post treated with solidagenone, all tested doses of resulted in an antidepressant-like effect evidenced by the decrease in immobility time in the TST. This effect was accompanied by a decrease in the MPO activity and in the IL-6 and TNF levels in the cortex in parallel to the increase in catalase activity.

CONCLUSIONS

The solidagenone has a promissor antidepressant-like potential, which can result of its beneficial action in the neuroinflammation process and due its antioxidant capability at the central nervous system.

Distinctive body perception mechanisms in high versus low symptom reporters: A neurophysiological model for medically-unexplained symptoms

OBJECTIVE

The neurophysiological processes involved in the generation of medically-unexplained symptoms (MUS) remain unclear. This study tested three assumptions of the perception-filter model contributing to MUS: (I.) increased bodily signal strength (II.) decreased filter function, (III.) increased perception.

METHODS

In this cross-sectional, observational study, trait MUS were assessed by a web-based survey (N = 486). The upper and lower decile were identified as extreme groups of high (HSR; n = 29; 26 women; Mage = 26.0 years) and low symptom reporters (LSR; n = 29; 21 women; Mage = 28.4 years). Mean heart rate (HR) and heart rate variability (HRV), and cortisol awakening response (CAR) were assessed as indicators of bodily signal strength (I.). Heartbeat-evoked potentials (HEPs) were assessed during rest and a heartbeat perception task. HEPs reflect attentional resources allocated towards heartbeats and served as index of filter function (II.). Interoceptive accuracy (IAc) in heartbeat perception was assessed as an indicator of perception (III.).

RESULTS

HSR showed higher HR and lower HRV (RMSSD) than LSR (I.), but no differences in CAR. HSR exhibited a stronger increase of HEPs when attention was focused on heartbeats than LSR (II.); there were no group differences in IAc (III.).

CONCLUSIONS

The perception-filter model was partially confirmed in that HSR showed altered bodily signals suggesting higher sympathetic activity (I.); higher HEP increases indicated increased filter function for bodily signals (II.). As more attentional resources are mobilized to process heartbeats, but perception accuracy remains unchanged (III.), this overflow could be responsible for detecting minor bodily changes associated with MUS.

Comorbidities of Patients with Functional Somatic Syndromes Before, During and After First Diagnosis: A Population-based Study using Bavarian Routine Data

Functional somatic syndromes (FSS) are characterised by the presence of one or multiple chronic symptoms that cannot be attributed to a known somatic disease. They are thought to arise though a complex interaction of biological and psychosocial factors, but it is unclear whether they share a common aetiology. One hypothesis supported by recent studies is that the FSS are postinfectious disorders, as is widely recognised for a subset of patients with irritable bowel syndrome. Our study used claims data submitted by office-based physicians to compare groups of patients with different FSS in the five years before and after the point of first diagnosis. Even five years prior to diagnosis, FSS patients consulted more frequently for a range of psychological and somatic conditions than did controls. Following diagnosis, consultation rates increased further and remained persistently high. Five years after diagnosis, between 34% (somatization disorder) and 66% (fibromyalgia) of patients were still being treated for the condition. Both prior gastrointestinal and upper-respiratory infection were associated with an increased risk of developing an FSS. We therefore recommend that patients at risk should be identified at an early stage and the underlying psychosocial and somatic issues addressed to prevent progression of the condition.

A meta-analysis of heart rate variability in major depression

BACKGROUND

Major depression (MD) is a risk factor for cardiovascular disease. Reduced heart rate variability (HRV) has been observed in MD. Given the predictive value of HRV for cardiovascular health, reduced HRV might be one physiological factor that mediates this association.

METHODS

The purpose of this study was to provide up-to-date random-effects meta-analyses of studies which compare resting-state measures of HRV between unmedicated adults with MD and controls. Database search considered English and German literature to July 2018.

RESULTS

A total of 21 studies including 2250 patients and 1982 controls were extracted. Significant differences between patients and controls were found for (i) frequency domains such as HF-HRV [Hedges' g = -0.318; 95% CI (-0.388 to -0.247)], LF-HRV (Hedges' g = -0.195; 95% CI (-0.332 to -0.059)], LF/HF-HRV (Hedges' g = 0.195; 95% CI (0.086-0.303)] and VLF-HRV (Hedges' g = -0.096; 95% CI (-0.179 to -0.013)), and for (ii) time-domains such as IBI (Hedges' g = -0.163; 95% CI (-0.304 to -0.022)], RMSSD (Hedges' g = -0.462; 95% CI (-0.612 to -0.312)] and SDNN (Hedges' g = -0.266; 95% CI (-0.431 to -0.100)].

CONCLUSIONS

Our findings demonstrate that all HRV-measures were lower in MD than in healthy controls and thus strengthens evidence for lower HRV as a potential cardiovascular risk factor in these patients.

Values of Cytokines and Tryptophan Metabolites over a 12 Weeks Time Course in Patients with Depression and Somatoform Disorder

Objective

Previous studies have suggested alterations in the kynurenine pathway as a major link between cytokine and neurotransmitter abnormalities in psychiatric disorders. Most of these studies used a cross-sectional case-control study design. However, knowledge is still lacking regarding the stability over time of kynurenine pathway metabolites and the functionally related cytokines. Therefore, we studied the stability of cytokines and tryptophan (TRP) parameters over a period of 12 weeks.

Methods

A total of 117 participants-39 with major depression, 27 with somatoform disorder, and 51 healthy controls were enrolled. Four evaluations, including blood withdrawal and psychometric testing, were performed over a period of 12 weeks. We used ELISA to measure interleukin (IL)-6, IL-1 receptor antagonist (RA) and tumor necrosis factor α (TNF α). High-performance liquid chromatography was used to analyze neurotransmitter variables, i.e. TRP, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), 3-OH-kynurenine (3-HK), and kynurenic acid (KYNA).

Results

We found no significant fluctuations of TRP, its metabolites (5-HIAA, KYN, KYNA, and 3-HK), or the cytokines (IL-1RA, IL-6, and TNF α) in any of the groups over the 12 weeks.

Conclusion

To our knowledge, this is the first longitudinal study performed in psychiatric patients to verify the stability and consequently the reliability of the biological parameters we investigated. Our data indicate that TRP metabolites and cytokines are reliable biological parameters in psychiatric research because they do not fluctuate significantly over time.

Somatic symptoms in adolescence as a predictor of severe mental illness in adulthood: a long-term community-based follow-up study

BACKGROUND

Somatic symptoms are common and costly for society and correlate with suffering and low functioning. Nevertheless, little is known about the long-term implications of somatic symptoms. The objective of this study was to assess if somatic symptoms in adolescents with depression and in their matched controls predict severe mental illness in adulthood by investigating the use of hospital-based care consequent to different mental disorders.

METHODS

The entire school population of 16-17-year-olds in the city of Uppsala, Sweden, was screened for depression in 1991-1993 (n = 2300). Adolescents with positive screenings (n = 307) and matched non-depressed controls (n = 302) participated in a semi-structured diagnostic interview for mental disorders. In addition, 21 different self-rated somatic symptoms were assessed. The adolescents with depression and the matched non-depressed controls were engaged in follow-up through the National Patient Register 17-19 years after the baseline study (n = 375). The outcome measures covered hospital-based mental health care for different mental disorders according to ICD-10 criteria between the participants' ages of 18 and 35 years.

RESULTS

Somatic symptoms were associated with an increased risk of later hospital-based mental health care in general in a dose-response relationship when adjusting for sex, adolescent depression, and adolescent anxiety (1 symptom: OR = 1.63, CI 0.55-4.85; 2-4 symptoms: OR = 2.77, 95% CI 1.04-7.39; ≥ 5 symptoms: OR = 5.75, 95% CI 1.98-16.72). With regards to specific diagnoses, somatic symptoms predicted hospital-based care for mood disorders when adjusting for sex, adolescent depression, and adolescent anxiety (p < 0.05). In adolescents with depression, somatic symptoms predicted later hospital-based mental health care in a dose-response relationship (p < 0.01). In adolescents without depression, reporting at least one somatic symptom predicted later hospital-based mental health care (p < 0.05).

CONCLUSIONS

Somatic symptoms in adolescence predicted severe adult mental illness as measured by hospital-based care also when controlled for important confounders. The results suggest that adolescents with somatic symptoms need early treatment and extended follow-up to treat these specific symptoms, regardless of co-occurring depression and anxiety.

Features of Resting-State Electroencephalogram Theta Coherence in Somatic Symptom Disorder Compared With Major Depressive Disorder: A Pilot Study

OBJECTIVE

Somatic symptom disorder (SSD) often co-occurs with major depressive disorder (MDD). Both conditions share common psychobiological and biobehavioral characteristics, but little is known about differential patterns in brain function. In this study, we compared resting-state functional brain connectivity between SSD and MDD using quantitative electroencephalography.

METHODS

Fifteen patients with SSD (SSD group), 15 patients with MDD (MDD group), and 15 healthy volunteers (healthy control [HC] group) participated in this study. Participants were assessed with quantitative electroencephalography using a 21-channel electroencephalogram system. Electroencephalogram coherence in the theta frequency range (3.5-7.5 Hz) was assessed between the following seven electrode pairs: Fp1 and Fp2, F7 and T3, F8 and T4, T5 and P3, P4 and T6, P3 and Pz, and Pz and P4. Differences in coherence between groups were analyzed using analysis of variance.

RESULTS

Theta coherence between the F7 and T3 electrodes was lower in the SSD group than the MDD and HC groups (F(2,42) = 6.67, p = .0030). Theta coherence between the T5 and P3 electrodes was lower in the SSD and MDD groups than the HC group (F(2,42) = 5.65, p = .0067). Theta coherence between the Pz and P4 electrodes was lower in the SSD group than the MDD group (F(2,42) = 6.41, p = .0037).

CONCLUSIONS

Both SSD and MDD patients commonly showed decreased functional connectivity within the left temporoparietal junction, which has neurophysiological implications for cognitive-attentional processing and social interaction. Frontostriatal circuit dysfunction affects processes that control perception and emotion, as well as misperception of somatosensory data in the parietal somatosensory area, and is more likely to be a neuropathology of SSD than MDD.

Stability of Cellular Immune Parameters over 12 Weeks in Patients with Major Depression or Somatoform Disorder and in Healthy Controls

OBJECTIVE

Cellular immune status in major depression (MD) patients differs from that in somatoform disorder (SFD) patients and healthy controls (HC). It is still questionable whether the patterns of immune parameters remain stable over time. Therefore, we studied lymphocyte and monocyte cell counts and neopterin levels in peripheral blood of MD and SFD patients and HC over 12 weeks and tested for correlations between biochemical and psychometric parameters.

METHODS

Thirty-nine patients with MD, 27 with SFD, and 51 HC were recruited. Peripheral blood was drawn at four visits, at 4-week intervals. We assessed the total cell count of B lymphocytes, natural killer (NK) cells, T lymphocyte subpopu-lations, and monocytes by flow cytometry, and neopterin serum levels by ELISA. Psychometric parameters were measured with questionnaires.

RESULTS

Counts of lymphocytes, monocytes, and neopterin were stable in the SFD and HC groups. In the MD group, total CD3+, CD3+CD8+, NK cells, and CD3+CD25+ T cells showed inhomogeneous variances in Friedman tests, particularly in females. Neopterin correlated with depressed mood in MD patients, and with body mass index in HC.

CONCLUSIONS

Cellular immune parameters are stable in HC and SFD. Our results may indicate influences of MD and gender on some cellular immune parameters. This may need to be considered in future immunological studies.

Common Etiological Sources of Anxiety, Depression, and Somatic Complaints in Adolescents: A Multiple Rater twin Study

Somatic complaints in children and adolescents may be considered part of a broader spectrum of internalizing disorders that include anxiety and depression. Previous research on the topic has focused mainly on the relationship between anxiety and depression without investigating how common somatic symptoms relate to an underlying factor and its etiology. Based on the classical twin design with monozygotic and dizygotic twins reared together, our study aimed to explore the extent to which the covariation between three phenotypes in adolescent girls and boys can be represented by a latent internalizing factor, with a focus on both common and specific etiological sources. A population-based sample of twins aged 12-18 years and their mothers and fathers (N = 1394 families) responded to questionnaire items measuring the three phenotypes. Informants' ratings were collapsed using full information maximum likelihood estimated factor scores. Multivariate genetic analyses were conducted to examine the etiological structure of concurrent symptoms. The best fitting model was an ACE common pathway model without sex limitation and with one substantially heritable (44%) latent factor shared by the phenotypes. Concurrent symptoms also resulted from shared (25%) and non-shared (31%) environments. The factor loaded most on depression symptoms and least on somatic complaints. Trait-specific influences explained 44% of depression variance, 59% of anxiety variance, and 65% of somatic variance. Our results suggest the presence of a general internalizing factor along which somatic complaints and mental distress can be modeled. However, specific influences make the symptom types distinguishable.

In vivo β-adrenergic receptor responsiveness: ethnic differences in the relationship with symptoms of depression and fatigue

BACKGROUND

Depressive symptoms and fatigue frequently overlap in clinical samples and the general population. The link of depressive symptoms and fatigue with increased risk of cardiovascular disease has been partly explained by shared biological mechanisms including sympathetic overactivity. Prolonged sympathetic overactivity downregulates the responsiveness of the β-adrenergic receptor (β-AR), a receptor that mediates several end-organ sympathetic responses.

PURPOSE

The authors studied whether depression and fatigue are related to reduced β-AR responsiveness within the human body (in vivo) in an ethnically diverse sample of African and Caucasian Americans.

METHODS

The chronotropic25 dose (CD25) was used to determine in vivo β-AR responsiveness in 93 healthy participants. Psychometric measures included the Center of Epidemiological Studies-Depression Scale and the Multidimensional Fatigue Symptom Inventory.

RESULTS

Hierarchical regression analyses (adjusted for age, gender, body mass index, blood pressure, smoking, and ethnicity) revealed that mental fatigue was significantly related to reduced β-AR responsiveness (i.e., higher CD25 values) in the whole sample. Moderation analyses indicated significant ethnicity × depression/fatigue interactions. Depressive symptoms, total fatigue, emotional fatigue, mental fatigue, and physical fatigue were related to reduced β-AR responsiveness in Caucasian American but not in African Americans.

CONCLUSIONS

Our findings suggest that symptoms of depression and fatigue are related to decreased in vivo β-AR responsiveness in Caucasian Americans. The lack of this association in African Americans highlights the importance for considering ethnicity as a potential moderator in research focusing on associations between psychological variables and cardiovascular function.

Childhood somatic complaints predict generalized anxiety and depressive disorders during young adulthood in a community sample

BACKGROUND

Children with somatic complaints are at increased risk for emotional disorders during childhood. Whether this elevated risk extends into young adulthood - and to which specific disorders - has rarely been tested with long-term prospective-longitudinal community samples. Here we test whether frequent and recurring stomach aches, headaches, and muscle aches during childhood predict emotional disorders in adulthood after accounting for childhood psychiatric and physical health status and psychosocial adversity.

METHOD

The Great Smoky Mountains Study is a community representative sample with 1420 participants. Children/adolescents were assessed 4-7 times between ages 9-16 years. They were assessed again up to three times between ages 19-26 years. Childhood somatic complaints were coded when subjects or their parents reported frequent and recurrent headaches, stomach aches, or muscular/joint aches at some point when children were aged 9-16 years. Psychiatric disorders were assessed with the Child and Adolescent Psychiatric Assessment and the Young Adult Psychiatric Assessment.

RESULTS

Frequent and recurrent somatic complaints in childhood predicted adulthood emotional disorders. After controlling for potential confounders, predictions from childhood somatic complaints were specific to later depression and generalized anxiety disorder. Long-term predictions did not differ by sex. Somatic complaints that persisted across developmental periods were associated with the highest risk for young adult emotional distress disorders.

CONCLUSIONS

Children from the community with frequent and recurrent physical distress are at substantially increased risk for emotional distress disorders during young adulthood. Preventions and interventions for somatic complaints could help alleviate this risk.

Childhood adversities and laboratory pain perception

Childhood adversity has frequently been related to a wide range of psychosomatic complaints in adulthood. The present study examined the relationship between different forms of childhood adversity and laboratory measures of pain. Heat pain tolerance and perceived heat pain intensity were measured in a community-based sample of 62 women (aged 20-64 years). Participants completed the Childhood Trauma Questionnaire (CTQ), which assesses five forms of childhood adversity: physical abuse, sexual abuse, emotional abuse, physical neglect, and emotional neglect. Somatic symptoms, depressive symptoms, and pain catastrophizing were assessed as potential mediators. Bivariate analyses indicated that emotional abuse but no other forms of childhood adversity were significantly related to decreased heat pain tolerance (r=-0.27; P<0.05). Accordingly, multiple regression analyses revealed that only emotional abuse was a significant predictor of heat pain tolerance (β=-0.62; P=0.034) when entering all CTQ subscales simultaneously. Although emotional abuse was also related to somatic symptoms, depressive symptoms, and pain catastrophizing, none of these variables mediated the relationship between childhood adversity and laboratory pain (P>0.1). No significant associations were found between any forms of childhood adversity and heat pain intensity. Our findings indicate that the severity of emotional childhood abuse is associated with decreased pain tolerance, an affective component of pain, but not with heat pain intensity, which has been described as a sensory component of pain.

Recognition of facially expressed emotions in patients with fibromyalgia syndrome

The study investigated the ability to identify facially expressed emotions in fibromyalgia syndrome (FMS) and its association with clinical parameters. Thirty-five FMS patients and 35 healthy controls accomplished a face recognition task. Additionally, pain severity, alexithymia, depression, anxiety, psychiatric co-morbidity and medication use were assessed. The patients displayed reduced task performance in terms of more misclassifications of emotional expressions than controls. Pain severity, alexithymia, depression and anxiety were inversely related to recognition performance, with pain severity accounting for the largest portion of test score variance. Psychiatric co-morbidity and medication had no impact on performance. The study documented impaired emotion recognition in FMS, which may contribute to the interpersonal difficulties and reduced social functioning related to this condition. As potential mechanisms mediating the occurrence of the deficits, altered affective processing due to interoceptive impairment as well as interference of central nervous nociceptive activity with cognitive and emotional processing are discussed.

Blunted exercise-induced mobilization of monocytes in somatization syndromes and major depression

BACKGROUND

Previous research indicates that physical activity may alter the number of immune cells. We examined whether increasing or decreasing the level of physical activity affects circulating lymphocyte and monocyte counts in patients with somatization syndromes and patients with major depression.

METHODS

Thirty-eight participants with major depression, 26 participants with somatization syndromes and 47 healthy controls participated in the study. Using an experimental within-subject design, participants were involved in 1 week of increased physical activity (daily exercise sessions) and 1 week of reduced physical activity. Counts of total lymphocytes, lymphocyte subsets and monocytes were determined before and after each trial. Linear mixed models adjusted for sex, body mass index, age, fitness status and the order of trials were used for longitudinal data analysis.

RESULTS

One week of exercise increases the number of monocytes in healthy controls (p<.05), but not in patients with somatization syndromes or patients with major depression. In addition, after 1 week of exercise, depressive symptoms were reduced in patients with major depression (p<.05) while somatoform symptoms were reduced (p<.05) in both clinical groups. Baseline comparisons and mixed models indicated reduced T helper cell counts in patients with somatization syndromes.

LIMITATIONS

Relatively small sample size. The time of physical activity was relatively short and restricted to low-graded exercise.

CONCLUSIONS

This study demonstrates a blunted mobilization of monocytes by exercise in both patients with somatization syndromes and patients with major depression. In addition, even one week of exercise reduces somatoform and depressive symptoms.

Reduced hypothalamic-pituitary-adrenal axis activity in chronic multi-site musculoskeletal pain: partly masked by depressive and anxiety disorders

BACKGROUND

Studies on hypothalamic-pituitary-adrenal axis (HPA-axis) function amongst patients with chronic pain show equivocal results and well-controlled cohort studies are rare in this field. The goal of our study was to examine whether HPA-axis dysfunction is associated with the presence and the severity of chronic multi-site musculoskeletal pain.

METHODS

Data are from the Netherlands Study of Depression and Anxiety including 1125 subjects with and without lifetime depressive and anxiety disorders. The Chronic Pain Grade questionnaire was used to determine the presence and severity of chronic multi-site musculoskeletal pain. Subjects were categorized into a chronic multi-site musculoskeletal pain group (n = 471) and a control group (n = 654). Salivary cortisol samples were collected to assess HPA-axis function (awakening level, 1-h awakening response, evening level, diurnal slope and post-dexamethasone level).

RESULTS

In comparison with the control group, subjects with chronic multi-site musculoskeletal pain showed significantly lower cortisol level at awakening, lower evening level and a blunted diurnal slope. Lower cortisol level at awakening and a blunted diurnal slope appeared to be restricted to those without depressive and/or anxiety disorders, who also showed a lower 1-h awakening response.

CONCLUSIONS

Our results suggest hypocortisolemia in chronic multi-site musculoskeletal pain. However, if chronic pain is accompanied by a depressive or anxiety disorder, typically related to hypercortisolemia, the association between cortisol levels and chronic multi-site musculoskeletal pain appears to be partly masked. Future studies should take psychopathology into account when examining HPA-axis function in chronic pain.

Health beliefs, low mood, and somatizing tendency: contribution to incidence and persistence of musculoskeletal pain with and without reported disability

OBJECTIVE

This study aims to investigate whether associations of psychological risk factors with the incidence and persistence of disabling musculoskeletal pain differ from those for non-disabling musculoskeletal pain.

METHODS

As part of the international Cultural and Psychosocial Influences in Disability (CUPID) study, 1105 Spanish nurses and office workers were asked at baseline about health beliefs concerning pain, mental health, and somatizing tendency. Musculoskeletal pain in the past months at ten anatomical sites (back, neck, and left and right shoulder, elbow, wrist/hand, and knee) was ascertained at baseline and one year later. Pain was classed as disabling if it made ≥1 specified everyday activities difficult or impossible. Multilevel multinomial logistic regression modeling was used to explore associations of baseline risk factors with pain outcomes at follow-up, conditioned on pain status at baseline.

RESULTS

A total of 971 participants (87.9%) completed follow-up. Among anatomical sites that were pain-free at baseline, the development of disabling musculoskeletal pain was predicted by pessimistic beliefs about pain prognosis [odds ratio (OR) 1.5, 95% confidence interval (95% CI) 1.0-2.1], poor mental health (OR 2.0, 95% CI 1.3-3.0), and somatizing tendency (OR 4.0, 95% CI 2.5-6.4). Adverse beliefs about prognosis were also associated with the transition from non-disabling to disabling musculoskeletal pain (OR 3.7, 95% CI 1.1-12.5) and the persistence of disabling musculoskeletal pain (OR 2.5, 95% CI 1.2-5.5), which was already present at baseline. Associations with non-disabling musculoskeletal pain were weaker and less consistent.

CONCLUSION

Our findings suggest that established psychological risk factors relate principally to the disability that arises from musculoskeletal pain.

Increased soluble interleukin-2 receptor levels are related to somatic but not to cognitive-affective features in major depression

Cell-mediated immune activation may play a role in the pathogenesis of depression as indicated by findings of increased soluble tumor necrosis factor receptor (sTNF-R) levels and meta-analytic evidence for elevated soluble interleukin-2 receptor (sIL-2R) concentrations. However, little research has been done on how these soluble cytokine receptors are differently related to specific features in patients with depression. We measured levels of the soluble cytokine receptors sIL-2R, sTNF-R1 and sTNF-R2 in 25 non-medicated patients with major depression (DSM-IV) and 22 healthy controls. Psychometric measures included cognitive-affective depressive symptoms, somatoform symptoms, somatic and cognitive dimensions of anxiety and current mood states. While patients with depression showed increased levels of sIL-2R (p<0.01), differences in sTNF-R1 (p=0.09) and sTNF-R2 (p=0.08) marginally failed to reach significance. Increased concentrations of sIL-2R were related to somatic measures such as the severity of somatoform symptoms and somatic anxiety symptoms but not to cognitive-affective measures or current mood states. Our findings may suggest some specificity in the relationship between sIL-2R and symptom dimensions and highlight potential pathways by which T cell mediated immune activation may underpin somatic symptoms in depression.

Pituitary volumes are reduced in patients with somatization disorder

OBJECTIVE

Despite of the suggested physiological relationship between somatoform disorder and disturbances in HPA axis function no volumetric study of pituitary volumes in somatization disorder has been carried out. Therefore, we aimed to use structural MRI to evaluate the pituitary volumes of the patients with somatization disorder.

METHODS

Eighteen female patients with somatization disorder according to DSM-IV and same number of healthy controls were included into the study. All subjects were scanned using a 1.5-T General Electric (GE; Milwaukee, USA) scanner. Pituitary volume measurements were determined by using manuallly tracings according to standard antomical atlases.

RESULTS

It was found significantly smaller pituitary volumes of the whole group of somatization patients compared to healthy (t=-3.604, p=0.001). ANCOVA predicting pituitary volumes demonstrated a significant main effect of diagnostic group (F=13.530, p<0.001) but TBV (F=1.924, p>0.05) or age (F=1.159, p>0.05). It was determined that there was no significant correlation between smaller pituitary volumes and the duration of illness (r=0.16, p>0.05) in the patient group.

CONCLUSION

In conclusion, we suggest that the patients with somatization disorder might have significantly smaller pituitary volumes compared to healthy control subjects.

Genetic co-morbidity between neuroticism, anxiety/depression and somatic distress in a population sample of adolescent and young adult twins

BACKGROUND

Genetic studies in adults indicate that genes influencing the personality trait of neuroticism account for substantial genetic variance in anxiety and depression and in somatic health. Here, we examine for the first time the factors underlying the relationship between neuroticism and anxiety/depressive and somatic symptoms during adolescence.

METHOD

The Somatic and Psychological Health Report (SPHERE) assessed symptoms of anxiety/depression (PSYCH-14) and somatic distress (SOMA-10) in 2459 adolescent and young adult twins [1168 complete pairs (35.4% monozygotic, 53% female)] aged 12-25 years (mean=15.5 ± 2.9). Differences between boys and girls across adolescence were explored for neuroticism, SPHERE-34, and the subscales PSYCH-14 and SOMA-10. Trivariate analyses partitioned sources of covariance in neuroticism, PSYCH-14 and SOMA-10.

RESULTS

Girls scored higher than boys on both neuroticism and SPHERE, with SPHERE scores for girls increasing slightly over time, whereas scores for boys decreased or were unchanged. Neuroticism and SPHERE scores were strongly influenced by genetic factors [heritability (h(2)) = 40-52%]. A common genetic source influenced neuroticism, PSYCH-14 and SOMA-10 (impacting PSYCH-14 more than SOMA-10). A further genetic source, independent of neuroticism, accounted for covariation specific to PSYCH-14 and SOMA-10. Environmental influences were largely specific to each measure.

CONCLUSIONS

In adolescence, genetic risk factors indexed by neuroticism contribute substantially to anxiety/depression and, to a lesser extent, perceived somatic health. Additional genetic covariation between anxiety/depressive and somatic symptoms, independent of neuroticism, had greatest influence on somatic distress, where it was equal in influence to the factor shared with neuroticism.

Depression and epilepsy, pain and psychogenic non-epileptic seizures: clinical and therapeutic perspectives

The clinical manifestations of depression in people with epilepsy (PWE) are pleomorphic, often associated with anxiety symptoms and anxiety disorders. The ongoing debate of whether the clinical presentation of depression in PWE is unique to this neurologic disorder is reviewed. Comorbid depression can impact the recruitment of PWE for pharmacologic trials with antiepileptic drugs (AEDs). Yet, the impact of depression on the response of the seizure disorder to pharmacotherapy with AEDs and its impact on worse adverse events may bias the interpretation of the trial findings, particularly when depressed patients are included in the AED trials. PWE have a greater suicidal risk than the general population. This risk is mediated by multiple factors, and recent data from the FDA have imputed a potential pathogenic role to all AEDs. The recognition of patients at risk is reviewed. Yet, the validity of the FDA data has been questioned, and the status of this controversial question is analyzed. As in the case of epilepsy, depression and pain syndromes have a relatively high comorbidity. The negative impact of depression on pain is reminiscent of that of depression in PWE; furthermore, the high comorbidity may be also associated with the existence of common pathogenic mechanisms. Neurologists and in particular, epileptologists establish the diagnosis of psychogenic non-epileptic seizures (PNES) in whom a comorbid depressive disorder is very often identified. The role of depression in the course of PNES and its treatment are discussed. Scarce data are available on the treatment of depression in PWE. Thus, clinicians have had to adopt data from patients with primary depressive disorders. We outline a consensus strategy on the identification and treatment of depressive disorders in adult and pediatric patients with epilepsy.

Association of symptoms of depression with progression of CKD

BACKGROUND

Depression is related to morbidity and mortality in patients with kidney failure treated by dialysis, but its influence on patients with earlier stages of chronic kidney disease (CKD) is uncertain. This study investigates the association of depressive symptoms with clinical outcomes in patients with CKD not requiring dialysis.

STUDY DESIGN

Prospective observational cohort study.

SETTING & PARTICIPANTS

568 participants with CKD not requiring maintenance dialysis were recruited consecutively at a tertiary hospital in Southern Taiwan and followed up for 4 years.

PREDICTORS

Baseline status of depressive symptoms.

OUTCOMES

The primary outcome is a composite of progression to end-stage renal disease (ESRD), defined as requiring maintenance dialysis treatment, or all-cause mortality; and secondary outcome was first hospitalization.

MEASUREMENTS

Depressive symptoms were assessed by Beck Depression Inventory. Estimated glomerular filtration rate (eGFR) was computed using the 4-variable MDRD (Modification of Diet in Renal Disease) Study equation.

RESULTS

428 participants completed the questionnaires and 160 (37%) had depressive symptoms. During a mean follow-up of 25.2 ± 11.9 months, 136 participants (32%) reached the primary outcome (119 reached ESRD and 17 died) and 110 participants (26%) were hospitalized. High depressive symptoms increased the risk of progression to ESRD or death (HR, 1.66; 95% CI, 1.14-2.44) and first hospitalization (HR, 1.59; 95% CI, 1.03-2.47). Participants with high depressive symptoms had more rapid GFR decrease (eGFR slopes of -2.3 [25th-75th percentile, -5.3 to -0.4] vs -1.2 [25th-75th percentile, -3.5 to 0.3] mL/min/1.73 m(2) per year; P = 0.001) and initial dialysis treatment at a higher eGFR (OR for initiation of dialysis at eGFR >5 mL/min/1.73 m(2), 4.45; 95% CI, 1.44-13.78).

LIMITATIONS

A single-center study of Taiwanese, Beck Depression Inventory evaluates only depressive symptom burden.

CONCLUSIONS

Depressive symptoms in CKD are independent predictors of adverse clinical outcomes, including faster eGFR decrease, dialysis therapy initiation, death, or hospitalization. Depression should be evaluated early and treated in patients with CKD.

Association of in vivo β-adrenergic receptor sensitivity with inflammatory markers in healthy subjects

OBJECTIVE

Several stress-related states and conditions that are considered to involve sympathetic overactivation are accompanied by increased circulating levels of inflammatory immune markers. Prolonged sympathetic overactivity involves increased stimulation of the β-adrenergic receptor (β-AR). Although prior research suggests that one mechanism by which sympathetic stimulation may facilitate inflammation is via β-AR activation, little work has focused on the relationship between circulating inflammatory immune markers and β-AR function within the human body (in vivo). We examined whether decreased β-AR sensitivity, an indicator of prolonged β-adrenergic overactivation and a physiological component of chronic stress, is related to elevated levels of inflammatory immune markers.

METHODS

Ninety-three healthy participants aged 19 to 51 years underwent the chronotropic 25 dose isoproterenol test to determine in vivo β-AR function. Circulating levels of C-reactive protein, interleukin 6, and soluble tumor necrosis factor receptor 1 were determined.

RESULTS

β-AR sensitivity was lower in people with higher C-reactive protein concentrations (r = 0.326, p = .003). That relationship remained significant after controlling for sociodemographic and health variables such as age, sex, ethnicity, body mass index, mean arterial blood pressure, heart rate, leisure-time exercise, and smoking status. No significant relationship was found between chronotropic 25 dose and interleukin 6 or soluble tumor necrosis factor receptor 1.

CONCLUSIONS

This study demonstrates a link between in vivo β-adrenergic receptor function and selected circulating inflammatory markers (CRP) in humans. Future studies in specific disease states may be promising.

Association between somatization subscale score and serotonin transporter availability in healthy volunteers--a single photon emission computed tomography study with [¹²³I] ADAM

RATIONALE AND OBJECTIVE

Serotonin is one of the key neuromodulators involved in fundamental cerebral functions and behaviors. Previous study has demonstrated that somatization symptoms are probably associated with central serotonergic circuits, which are implicated in anxiety and nociception regulation. This study aims to examine the correlation between somatization subscale score and serotonin transporter (SERT) availability in healthy volunteers.

METHODS

Sixty-four healthy participants, 26 males and 38 females, were enrolled from the community and were administered the single somatization subscale of the Chinese symptom checklist 90 revised (SCL90-R). Single photon emission computed tomography with [(123)I] 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine was also performed to examine SERT availability.

RESULTS

The somatization scores were negatively correlated with SERT availability (Spearman's ρ = -0.35, p = 0.005), particularly in males (Spearman's ρ = -0.54, p = 0.004).

CONCLUSION

This result reconfirmed the correlation between central serotonergic activity and the intensity of somatization symptoms, even in healthy participants. However, a gender difference exists in this correlation.

Psychobiological aspects of somatization syndromes: contributions of inflammatory cytokines and neopterin

Previous research suggests a dysregulation of immune-to-brain communication in the pathophysiology of somatization syndromes (multiple somatoform symptoms). We compared blood levels of the inflammatory markers tumor necrosis factor-alpha (TNF-α), interleukin-1 receptor antagonist (IL-1ra), interleukin-6 (IL-6) and neopterin between 23 patients with somatization syndromes (Somatoform Symptom Index-8, SSI-8), 23 age- and sex-matched healthy controls and 23 patients with major depression. No group differences were found for IL-1ra and IL-6. While TNF-α was increased in both clinical groups, neopterin was only increased in somatization syndromes. Correlational analyses revealed that neopterin tended to be related to somatoform pain complaints in patients with somatization syndromes. This study is the first to demonstrate increased levels of TNF-α and neopterin in patients with somatization syndromes without a diagnosis of depression, which may support a role of immune alterations in somatization syndromes. Neopterin is a reliable indicator for interferon-γ (IFN-γ) which was identified as the only cytokine that induces significant production of neopterin. Considering recent research indicating that IFN-γ can lead to increased neuronal responsiveness and body perceptions by reducing inhibitory tone in the dorsal horn, the observed association between somatization syndromes and neopterin might support the idea of central sensitization in the pathogenesis of somatoform symptoms.

Long-term course of pain in breast cancer survivors: a 4-year longitudinal study

After successful treatment of early breast cancer, many women still report pain symptoms, and attribute them to the previous illness or its treatment. However, knowledge about the long-term course of pain in breast cancer is limited. Baseline assessment included 3,088 women who received a breast cancer diagnosis on average 2 years prior to enrollment, and who completed typical medical treatments. After 4 years, a subsample of 2,160 recurrence-free women (70%) was re-assessed. The major outcome variable was the composite index for general pain symptoms. Over the 4-year course, a slight but significant increase in pain was reported. If only medical variables were examined, a triple interaction between surgery type, breast cancer stage, and time indicated that pain scores increased in most subgroups, while they decreased in stage II women after mastectomy and stage III women after lumpectomy. Using a regression analytical approach, psychological and other variables added significantly to the prediction of pain persistence. Regression analysis revealed that pain symptoms increased in those women taking tamoxifen at baseline, in those reporting depression at baseline or stressful life events during the first 12 months after enrollment. Exercise at baseline had a beneficial effect on pain recovery. The persistence or increase of pain symptoms in women surviving breast cancer is associated with some medical factors (surgery type, tamoxifen use), but also with psychological factors. Pain should be a standard outcome variable in the evaluation of cancer treatment programs.

Somatization in major depression--clinical features and genetic associations

OBJECTIVE

To identify clinical variables and genetic variations within monoaminergic genes known to be implicated in pain perception that are associated with the occurrence of somatization symptoms in patients with major depression.

METHOD

Somatization was evaluated using the respective subscale of the Symptom Checklist SCL-90-R. Six monoaminergic genes were identified showing an involvement in pain perception and somatization according to the literature: COMT, HTR2A, SLC6A2, SLC6A4, DRD4, and TPH1. One hundred and eighteen single nucleotide polymorphisms (SNPs) within these genes were genotyped using Illumina BeadChips in a sample of 398 at least moderately to severely depressed in-patients participating in the Munich Antidepressant Response Signature (MARS) project.

RESULTS

Thirty SNPs exhibit nominally significant associations with somatization. One SNP (rs9534505) located in intron 2 of the HTR2A gene withstood correction for multiple testing. Clinical data provide further evidence for strong impact of somatization on the presentation of depressive symptoms and description of a patient subgroup with unfavorable clinical outcome.

CONCLUSION

Our results demonstrate the influence of a HTR2A polymorphism on aspects of somatization in major depression, which co-occurs with an unfavorable antidepressant treatment outcome. These results confirm and expand previous findings on somatization as a risk factor for treatment outcome in major depression.

Depression, cytokines and experimental pain: evidence for sex-related association patterns

BACKGROUND

There is robust evidence that altered neural-immune interactions including increased levels of proinflammatory cytokines are involved in both the pathogenesis of depression and altered pain processing. Proinflammatory cytokines induce sickness behavior, a constellation of symptoms that bears a strong similarity to those of depression. A feature of sickness behavior is enhanced pain sensitivity and it has been suggested that proinflammatory cytokines interact with pain processing directly and via several neurobiological pathways. Previous research indicates that depression and pain are closely related. We investigated the association between proinflammatory cytokines and experimental pain in major depression.

METHODS

Psychopathological variables, pressure pain thresholds (PPT) and concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were measured in 37 outpatients with major depression and 48 healthy controls.

RESULTS

Compared with controls, depressed patients exhibited significantly higher levels of TNF-α and significantly decreased PPT indicating enhanced pain sensitivity. The group differences were robust when adjusting for sex and body mass index, although sex was significantly related to PPT. No group difference was observed in IL-6. PPT correlated significantly with TNF-α in women but not in men.

LIMITATIONS

Because of the cross-sectional design, causality of the relation between TNF-α and pain cannot be determined. Results should be considered preliminary given the small sample size.

CONCLUSION

The present findings suggest that increased pain sensitivity in depression may be linked to increased TNF-α concentration. The absence of this association in men is discussed in terms of pain-related psychobiological sex differences.