Persistence of abnormal cortisol levels in elderly persons after recovery from major depression

Background

Cortisol hypersecretion is characteristic of acute clinical depression, but little is known in fully recovered, non-treated elderly persons with a lifetime history of depression. This study was designed to examine patterns of diurnal cycle of cortisol in an elderly cohort without current depression or treatment for depression according to whether the person has or has not experienced a previous episode of depression or co-morbid depression with anxiety.

Methods

Cortisol secretion was evaluated in 162 community-dwelling elderly on a stressful and a non-stressful day (basal level). Past depression and anxiety disorders were assessed using a standardized psychiatric examination based on DSM-IV criteria (the Mini International Neuropsychiatric Interview).

Results

Antidepressant-free persons with a history of non-co-morbid major depression (6.8% of the sample) showed basal cortisol hypersecretion compared to those with depression and anxiety (8.6%) or controls. Several hours after exposure to a stressful situation, controls showed a sustained increase in cortisol secretion, which was not observed in persons with a history of depression. Persons with a history of depression with anxiety showed a similar cortisol secretion at baseline to controls but a heightened response to stressful situation; a pattern comparable to that observed in subjects with pure anxiety disorders (16.7%).

Conclusion

An abnormal HPA response persists even after effective treatment for depression. A history of co-morbid depression and anxiety gives rise to changes characteristic of anxiety alone. Our findings suggest that cortisol abnormalities may be trait markers for vulnerability to depression and for the differentiation of depression and depression with co-morbid anxiety.     

Sleep actigraphy pattern and behavioral/emotional difficulties in kindergarten children: Association with hypothalamic-pituitary-adrenocortical (HPA) activity

Background

Various studies of adult endocrinology and sleep show close connections between poor sleep quality, deterioration of the HPA axis and negative psychological characteristics. However, the extent to which these associations may have already emerged and developed in childhood remains unclear.

Methods

A total of 82 preschoolers (age 4.91 ± 0.48) underwent activity monitoring for seven consecutive days and nights, wearing a digital movement-measuring instrument. Additionally, on the first and on the last morning of sleep registration, the activity of the HPA axis was assessed via the amount of cortisol in the saliva. Psychological and behavioral assessments were also made.

Results

Three sub-groups of good (22%), normal (58.5%) and poor (19.5%) sleepers were distinguished. Poor sleep patterns were associated with higher HPA activity and with behavioral/emotional difficulties.

Conclusions

The interplay between unfavorable sleep patterns, deterioration of the HPA axis and behavioral/emotional difficulties is already apparent in pre-school children.     

Psychophysiological biomarkers of workplace stressors

Workplace stressors are associated with greater coronary heart disease risk, although there is debate over the psychophysiological consequences of work stress. This study builds on recent reviews and examines the literature linking work stress with sympatho-adrenal biomarkers (plasma catecholamines and heart rate variability) and HPA axis biomarkers - the post-morning profile of cortisol.

Methods

Relevant studies using appropriate search terms were searched using the bibliographic databases PubMed, Embase, Biosys and Toxline. Four studies on plasma catecholamines, 10 studies on heart rate variability, and 16 studies on post-morning cortisol were reviewed.

Results

In the majority of studies that examined the association of HRV and work stress, greater reports of work stress is associated with lower heart rate variability. The findings for plasma catecholamines and cortisol secretion are less clear cut and suffer from poorer quality of studies in general.

Conclusion

There is evidence that work stress is related to elevated stress responses in terms of sympatho-adrenal and HPA axis biomarkers.     

In pre-school children,cortisol secretion remains stable over 12 months and is related to psychological functioning and gender

Objectives

Cross-sectional studies provide evidence that cortisol secretion as a marker of hypothalamus-pituitary-adrenocortical axis activity (HPA AA) is related to psychological functioning and behavior. However, there are no studies of the stability of the HPA AA in pre-schoolers over the longer term. The aim of the present study was therefore to investigate cortisol secretion in pre-schoolers longitudinally, and to predict psychological functioning12 months later.

Method

92 pre-schoolers (mean age: 5.4 years; 44% females) took part in a follow-up assessment 12 months after initial assessment. Cortisol secretion was assessed both at baseline (morning cortisol secretion) and under challenge conditions, and a thorough psychological assessment was included.

Results

Increased cortisol secretion at 5.4 years predicted increased cortisol secretion and psychological difficulties at 6.4 years. Compared to boys, girls had higher cortisol secretion at both 5.4 and 6.4 years. Cross-sectionally, at the age of 6.4 years, levels of cortisol secretion impacted differentially on girls' and boys' behavior.

Conclusion

In pre-schoolers, HPA axis activity at 5.4 years is stable over the following 12 months and is associated with psychological functioning. Pre-schoolers with higher cortisol levels are at increased risk of developing further psychological difficulties. Gender affects the manner in which HPA axis activity impacts on psychological functioning. Moreover, gender differences in cortisol secretion occur already in prepubertal children and appear to be independent from sex steroids.     

Autoantibodies reacting with vasopressin and oxytocin in relation to cortisol secretion in mild and moderate depression

Background

Abnormal vasopressin (VP) and oxytocin (OT) signaling may contribute to the altered activity of the hypothalamo-pituitary-adrenal (HPA) axis in major depression; however, the underlying mechanisms remain uncertain. This study characterized plasma levels and affinities of OT- and VP-reactive autoantibodies (autoAbs) in relation to disease severity and plasma cortisol response to physical exercise in patients with mild and moderate depression and healthy controls.

Methods

Physical exercise was used to elicit plasma cortisol response in 23 male patients with depression and 20 healthy controls and plasma samples were obtained before and after the exercise. Just before the exercise, patients and controls were evaluated by the Montgomery and Åsberg Depression Rating Scale (MADRS) and divided according to depression severity (14 mild and 9 moderate). Plasma levels of total and free VP- and OT-reactive IgG, IgA and IgM autoAbs were measured by ELISA and affinity of IgG and IgM autoAbs were measured by plasmon resonance technique at baseline before the exercise and analyzed with relation to the MADRS and cortisol response. Immunohistochemistry was used to evaluate autoAbs binding to the rat hypothalamus.

Results

Plasma levels of OT- and VP-reactive total IgG autoAbs were lower in patients with moderate depression vs. controls and patients with mild depression. Plasma levels of both OT- and VP-free IgG autoAbs were negatively correlated with MADRS scores. Affinity values of IgG and IgM autoAbs for both OT and VP displayed 100 fold variability among patients or controls but no significant group differences were found. Patients with moderate depression displayed blunted response of cortisol secretion to physical exercise. Baseline levels of VP total IgG and IgM autoAbs correlated negatively and VP-free IgG autoAbs correlated positively with plasma cortisol after physical exercise. Immunostaining of magnocellular hypothalamic neurons of the supraoptic and paraventricular nuclei by plasma IgG was present in 35% of the depression and in 14% of the controls groups, but this staining was not abolished by plasma preabsorption with OT or VP peptides.

Conclusion

These data show that changes of levels but not affinity of OT- and VP-reactive autoAbs can be associated with the altered mood in subjects with moderate depression and that levels of VP-reactive autoAbs are associated with cortisol secretion.     

Social anxiety disorder women easily recognize fearfull, sad and happy faces: The influence of gender

Background

It has been suggested that individuals with social anxiety disorder (SAD) are exaggeratedly concerned about approval and disapproval by others. Therefore, we assessed the recognition of facial expressions by individuals with SAD, in an attempt to overcome the limitations of previous studies.

Methods

The sample was formed by 231 individuals (78 SAD patients and 153 healthy controls). All individuals were treatment naïve, aged 18-30 years and with similar socioeconomic level. Participants judged which emotion (happiness, sadness, disgust, anger, fear, and surprise) was presented in the facial expression of stimuli displayed on a computer screen. The stimuli were manipulated in order to depict different emotional intensities, with the initial image being a neutral face (0%) and, as the individual moved on across images, the expressions increased their emotional intensity until reaching the total emotion (100%). The time, accuracy, and intensity necessary to perform judgments were evaluated.

Results

The groups did not show statistically significant differences in respect to the number of correct judgments or to the time necessary to respond. However, women with SAD required less emotional intensity to recognize faces displaying fear (p = 0.002), sadness (p = 0.033) and happiness (p = 0.002), with no significant differences for the other emotions or men with SAD.

Conclusions

The findings suggest that women with SAD are hypersensitive to threat-related and approval-related social cues. Future studies investigating the neural basis of the impaired processing of facial emotion in SAD using functional neuroimaging would be desirable and opportune.     

Social support and oxytocin interact to suppress cortisol and subjective responses to psychosocial stress

Background

The presence of social support has been associated with decreased stress responsiveness. Recent animal studies suggest that the neuropeptide oxytocin is implicated both in prosocial behavior and in the central nervous control of neuroendocrine responses to stress. This study was designed to determine the effects of social support and oxytocin on cortisol, mood, and anxiety responses to psychosocial stress in humans.

Methods

In a placebo-controlled, double-blind study, 37 healthy men were exposed to the Trier Social Stress Test. All participants were randomly assigned to receive intranasal oxytocin (24 IU) or placebo 50 min before stress, and either social support from their best friend during the preparation period or no social support.

Results

Salivary free cortisol levels were suppressed by social support in response to stress. Comparisons of pre- and poststress anxiety levels revealed an anxiolytic effect of oxytocin. More importantly, the combination of oxytocin and social support exhibited the lowest cortisol concentrations as well as increased calmness and decreased anxiety during stress.

Conclusions

Oxytocin seems to enhance the buffering effect of social support on stress responsiveness. These results concur with data from animal research suggesting an important role of oxytocin as an underlying biological mechanism for stress-protective effects of positive social interactions.     

Anxiety disorders and suicidality in the National Comorbidity Survey-Replication

Objective

The current study sought to examine the unique associations between anxiety disorders and suicidality using a large nationally representative sample and controlling for a number of established risk factors for suicide.

Method

Data from the National Comorbidity Survey-Replication were used for analyses. Lifetime diagnostic history and demographics were obtained in this survey through a structured interview. Lifetime suicidal ideation and attempts were also assessed.

Results

Multivariate analyses covarying for psychiatric comorbidity and demographic variables found social anxiety disorder (SAD), posttraumatic stress disorder (PTSD), generalized anxiety disorder (GAD), and panic disorder (PD) to be unique predictors of suicidal ideation, while only SAD, PTSD, and GAD were predictive of suicide attempts. Analyses by gender indicated that each of these four disorders were predictive of suicidal ideation or suicide attempts among women, while only PTSD and PD acted as risk factors among men.

Conclusions

Findings provide further evidence of the negative impact of anxiety disorders, suggest efforts should be made towards their early detection and treatment, and emphasize the importance of suicide risk assessment in treating individuals with anxiety disorders.     

Acute panicogenic, anxiogenic and dissociative effects of carbon dioxide inhalation in patients with post-traumatic stress disorder (PTSD)

Background

Increased anxiety and panic to inhalation of carbon dioxide (CO₂) has been described in patients with anxiety disorders, especially panic disorder, compared to healthy subjects. Post-traumatic stress disorder (PTSD) has been hypothesised to resemble panic disorder and is currently classified as an anxiety disorder in DSM-IV. However, there are only very few data available about the sensitivity of patients with PTSD to CO₂.

Methods

In 10 patients with PTSD, 10 sex- and age-matched healthy subjects and 8 patients with panic disorder we assessed anxiety, panic, dissociative and PTSD symptoms before and after a single vital capacity inhalation of 35% CO₂.

Results

Patients with PTSD showed an increased anxiety, panic and dissociative reaction to the inhalation of 35% CO₂ compared to healthy participants. PTSD subjects’ responses were indistinguishable from those of panic patients. Additionally, PTSD-typical symptoms like post-traumatic flashbacks were provoked in patients with PTSD after the inhalation of CO₂.

Conclusions

In our sample, PTSD was associated with an increased CO₂ reactivity, pointing to an increased susceptibility of PTSD patients to CO₂ challenge.     

Effects of mirtazapine on dehydroepiandrosterone-sulfate and cortisol plasma concentrations in depressed patients

Background

Among the neuroactive steroids, dehydroepiandrosterone sulfate (DHEA-S) is at least in part produced in the adrenal gland and is therefore under the control of the hypothalamic-pituitary-adrenocortical (HPA)-system. In the present study, the impact of mirtazapine on DHEA-S and cortisol (COR) levels was investigated in relation to clinical response in depressed patients.

Methods

A total of 23 inpatients suffering from a major depressive episode (DSM-IV criteria) underwent 5-week treatment with mirtazapine (45 mg/day). Plasma samples were taken weekly at 0800 h and quantified for COR and DHEA-S levels.

Results

Mirtazapine significantly reduced both COR and DHEA-S concentrations, but had no impact on the COR/DHEA-S ratio. The percentage decrease of DHEA-S, but not that of COR was significantly and positively correlated with the percentage reduction in the sum score of the Hamilton Depression Rating Scale at week 5, suggesting a relationship between DHEA-S reduction and clinical efficacy of mirtazapine. There was a significant positive correlation between the decline in COR and DHEA-S levels.

Conclusions

Apparently, the decrease in COR and DHEA-S concentrations conjointly reflects an attenuating impact of mirtazapine on HPA axis activity, thereby decreasing the adrenal secretion of COR and DHEA-S.     

Neurosteroid Levels in Patients with Obsessive-Compulsive Disorder

Objective

Changes in serum neurosteroid levels have been reported in stress-related disorders such as anxiety and depression, but not in patients with obsessive-compulsive disorder (OCD). We thus investigated such changes in patients with OCD.

Methods

We compared the serum levels of progesterone, pregnanolone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEA-S), cortisol and testosterone in 30 patients with OCD and 30 healthy controls.

Results

When male and female patients were evaluated together, DHEA and cortisol levels were significantly higher in patients with OCD than the control group. When the genders were evaluated separately, DHEA and cortisol levels were higher in female patients than the female controls. The increase in DHEA levels in female patients is likely an effect of the hypothalamic-pituitary-adrenal (HPA) axis. In contrast, cortisol levels in male patients were higher than the control group, while testosterone levels were lower. The increased cortisol and decreased testosterone levels in male patients likely involves the hypothalamic-pituitary-gonadal (HPG) axis.

Conclusion

These findings suggest that neurosteroid levels in patients with OCD should be investigated together with the HPA and HPG axes in future studies.     

Attentional bias towards angry faces in childhood anxiety disorders

Objective

To examine attentional bias towards angry and happy faces in 8-12 year old children with anxiety disorders (n = 29) and non-anxious controls (n = 24).

Method

Children completed a visual-probe task in which pairs of angry/neutral and happy/neutral faces were displayed for 500 ms and were replaced by a visual probe in the spatial location of one of the faces.

Results

Children with more severe anxiety showed an attentional bias towards angry relative to neutral faces, compared with anxious children who had milder anxiety and non-anxious control children, both of whom did not show an attentional bias for angry faces. Unexpectedly, all groups showed an attentional bias towards happy faces relative to neutral ones.

Conclusions

Anxiety symptom severity increases attention to threat stimuli in anxious children. This association may be due to differing threat appraisal processes or emotion regulation strategies.     

Association of FKBP5 gene haplotypes with completed suicide in the Japanese population

Background

The hypothalamus-pituitary-adrenal (HPA) axis is known to have a role in suicidal behaviors in patients with affective disorders. However, the incomplete overlapping of the genetic factors of suicidal behaviors and the genetic factors of affective disorders suggest that the genes associated with predisposition to suicidal behaviors and affective disorders are different. There is increasing evidence that genes regulating the HPA axis have effects on suicidal behaviors. To test this idea, we examined the association of three HPA axis-related genes (glucocorticoid receptor (NR3C1), mineralocorticoid receptors (NR3C2), and FK506 binding protein 5 (FKBP5)) with suicide.

Methods

We selected 3 SNPs of the FKBP5 (rs3800373, rs1360780, and rs2395635), 2 SNPs of the NR3C1 (rs6196 and rs10052957), and 3 SNPs of the NR3C2 genes (rs5525, rs5522, and rs2070951) based on their frequency in the Japanese population. Using TaqMan probe assays, we determined these SNPs in 219 completed suicide victims and 228 age- and gender-matched healthy control subjects.

Results

No significant differences in genotypic distribution or allelic frequency of any single SNPs between the completed suicide and control groups were observed. The distributions of TT, TC, and GT haplotypes of the FKBP5 gene (comprised of rs3800373 and rs1360780) between the completed suicide and control groups were significantly different (p < 0.05 for each haplotype). The TC haplotype withstood correction for multiple comparisons (corrected p = 0.034).

Conclusion

Our results suggest that haplotypes in FKBP5 gene are associated with completed suicide. This finding needs to be confirmed using rigorous SNPs selection in a larger sample.     

Personality traits in multiple sclerosis: association with mood and anxiety disorders

Background

Patients with multiple sclerosis (MS) frequently experience depression and anxiety. Several studies also document personality differences between MS patients and controls. Few studies, however, have examined the relationship between mood/anxiety and core personality traits in MS.

Objectives

The purpose of the present investigation was to examine the association between anxiety, mood, and personality disturbances in MS.

Methods

A structured psychiatric interview and validated self-report measures of personality, depression, and anxiety were administered to 85 MS patients and 20 normal controls.

Results

Findings suggested a significant association between psychopathology and core personality dysfunction in MS. Depressed/anxious MS patients exhibited more neuroticism, less extroversion, less agreeableness, and less conscientiousness than mentally healthy MS patients and normal controls. In contrast, nondepressed/nonanxious MS patients' core personality traits did not substantially differ from normal controls.

Conclusions

Though longitudinal studies are needed, findings provide hope that the successful treatment of MS patients' mood and anxiety symptoms may also partially ameliorate disordered personality characteristics. Consistent with previous research, an increased understanding of MS patients' personality characteristics may also aid with preventative psychiatric and medical treatment.     

Impact of blue vs red light on retinal response of patients with seasonal affective disorder and healthy controls

Objectives

Seasonal affective disorder (SAD) is characterized by a mood lowering in autumn and/or winter followed by spontaneous remission in spring or summer. Bright light (BL) is recognized as the treatment of choice for individuals affected with this disease. It was speculated that BL acts on photosensitive retinal ganglion cells, particularly sensitive to blue light, which led to the emergence of apparatus enriched with blue light. However, blue light is more at risk to cause retinal damage. In addition, we reported using electroretinography (ERG) that a 60 min exposure of BL could reduce rod sensitivity. The goal of the present study was to verify if this decreased in sensitivity could be a consequence of the blue light portion present in the white light therapy lamps. We also wanted to assess the effect of monochromatic blue light vs red light in both healthy controls and patients with SAD.

Method

10 healthy subjects and 10 patients with SAD were exposed in a random order for 60 min to two different light colors (red or blue) separated by an interval of at least 1 day. Cone and rod ERG luminance-response function was assessed after light exposure.

Results

A two-way ANOVA indicates that blue light decreases the maximal ERG response (Vmax) in both groups in photopic (p < 0.05) and scotopic conditions (p < 0.01).

Conclusion

The main finding of this experiment is that blue light reduces photoreceptor responses after only a single administration. This brings important concerns with regard to blue-enriched light therapy lamps used to treat SAD symptoms and other disorders.     

Examining cortisol rhythmicity and responsivity to stress in children with Tourette syndrome

BACKGROUND: Tourette syndrome (TS) is characterized by motor and vocal tics, which are often exacerbated by stress. The hypothalamic-pituitary-adrenocortical (HPA) axis, a major stress response system is thus of interest for understanding TS. METHODS: Diurnal cortisol rhythms were estimated in medication-free children 7-13 years with TS (N=20) and healthy age-matched controls (N=16). Salivary samples were collected on 3 consecutive days from the home. HPA responsivity was assessed by examining cortisol in response to a mock and real MRI scan. RESULTS: The results of diurnal rhythmicity revealed a trend showing marginally lower evening cortisol for the TS group. By contrast, the TS group had higher cortisol levels in response to the stressor. There were strong, negative correlations between evening cortisol and tic severity as well as diurnal cortisol and anxiety. CONCLUSIONS: The children with TS showed increased cortisol in response to the MRI environment, supporting a model of enhanced HPA responsivity. The lower evening cortisol may be the result of chronic daily stress. Alternatively, the negative associations between cortisol and reported anxiety and tics may reflect biologically based anxiolytic properties of tic expression. Taken together, the results clearly implicate involvement of the HPA axis in the neuropathology of TS.     

Basal activity of the hypothalamic-pituitary-adrenal axis in patients with depersonalization disorder

Depersonalisation disorder may occur during severe anxiety or following a traumatic event, suggesting a possible role of stress hormones. This study investigated basal activity of the hypothalamic-pituitary-adrenal (HPA) axis in patients with depersonalisation disorder. Salivary cortisol levels were measured at four time points over 12 h in patients with depersonalisation disorder (N=13), major depressive disorder (MDD, N=14) and healthy controls (N=13). Beck Depression Inventory scores were significantly higher in depersonalised subjects than controls, while MDD subjects demonstrated higher scores than both groups. Basal cortisol levels of depersonalised subjects were significantly lower than those of MDD subjects but not healthy controls. These results point to reduced basal activity of the HPA axis in depersonalisation disorder. This pilot study supports the distinction between depersonalisation disorder and major depressive disorder which should be examined in a larger sample.     

Stimulation magnétique transcrânienne répétée (rTMS) et symptômes négatifs de la schizophrénie

Purpose

The author has endeavoured to present a qualitative review of current data on the interest of repetitive Transcranial Magnetic Stimulation (rTMS) in the treatment of negative symptoms of schizophrenia, its therapeutic impact and processes that underlie it.

Method

The method consisted in a review of the literature by an extensive consultation of the computerized Medline database.

Results

Despite the small number of controlled studies and the small sample sizes, rTMS appears to be an effective therapeutic method in the treatment of negative symptoms of schizophrenia and also helps understanding the patho-physiologic processes that underlie them (hypofrontality, dopamine hypothesis and responsiveness of the HPA axis).

Conclusion

Before any conclusion may be reached about the effectiveness of this new technology more studies are required using larger parameters for active treatment and optimal placebos (alpha-TMS at least 110 % of the motor threshold, focused on the hypo-active area).     

Depressive symptoms in persons with acute coronary syndrome: Specific symptom scales and prognosis

Objective

To determine which particular depressive symptom scales, derived from three scales, predicted poorer prognosis in persons with acute coronary syndrome (ACS).

Methods

Hospitalized ACS patients (n=408) completed questionnaires (depression, vital exhaustion). Mokken scaling derived unidimensional scales. Major cardiac events (cardiac mortality, ACS, unplanned revascularization) were assessed at median 67 weeks post event.

Results

Only depressive symptoms of fatigue-sadness predicted prognosis in univariate (hazard ratio [HR]=1.8, 95% CI 1.1-3.0, P=.025) and multivariate analysis (HR=1.8, 95% CI 1.1-2.9, P=.025). Symptoms of anhedonia (HR=1.6, 95% CI 0.9-2.8, P=.102) and depressive cognitions (HR=1.3, 95% CI 0.7-2.2, P=.402) did not.

Conclusion

Symptoms of fatigue-sadness, but not other symptoms, were associated with increased risk of major cardiac events. Depression should be considered as a multidimensional, rather than a unidimensional, entity when designing interventions.     

Genetic variation in neuroendocrine genes associates with somatic symptoms in the general population: Results from the EPIFUND study

Objective

Functional somatic syndromes commonly occur together, share a genetic component and are associated with numerous somatic symptoms. This study aimed to determine if genetic variation in two neuroendocrine systems, the serotoninergic system and the hypothalamic-pituitary-adrenal (HPA) axis, was associated with the number of reported somatic symptoms.

Methods

This population-based cohort study (Epidemiology of Functional Disorders) recruited participants from three primary care registers in the northwest of England. Somatic symptoms, anxiety, depression, and pain were assessed using the Somatic Symptoms Checklist, Hospital Anxiety and Depression scales, and body manikins, respectively, via a postal questionnaire. Tag Single Nucleotide Polymorphisms (SNPs) (r²>0.8) were selected for serotoninergic system genes (TPH2, SLC6A4 and HTR2A) and HPA axis genes (CRH, CRHR1, CRHBP, MC2R, POMC, NR3C1, and SERPINA6) and genotyped using Sequenom technology. Negative binomial regression was used to test for association between SNPs and the number of somatic symptoms. Stepwise-regression was used to identify independent effects and adjustments were made for anxiety, depression, and pain.

Results

A total of 967 subjects were successfully genotyped for 143 (87%) SNPs. Multiple SNP associations with the number of somatic symptoms were observed in HTR2A and SERPINA6 as well as two SNPs in TPH2. Stepwise regression identified two effects in HTR2A and a single effect in TPH2 which were independent of anxiety, depression, and pain. A single effect was also identified in SERPINA6 but was no longer significant when adjusted for pain.

Conclusion

This study finds association of SNPs in HTR2A, SERPINA6, and TPH2 with somatic symptoms implicating them as potentially important in the shared genetic component to functional somatic syndromes, although replication is required.