Platelet serotonin in combat related posttraumatic stress disorder with psychotic symptoms

Psychotic and Somatic Symptoms Are Frequent in Refugees With Posttraumatic Stress Disorder: A Narrative Review

OBJECTIVE

In 2021, 89.3 million refugees were vulnerable to posttraumatic stress disorder (PTSD) after exposure to multiple and repeated traumatic experiences. The recent war in Ukraine provoked 7 million refugees to flee their homes. Specific clinical presentations of PTSD in refugee populations may not be familiar to most physicians. The goal of this review is to describe the diagnosis and specific clinical features of PTSD in refugees.

METHODS

This narrative review of 263 articles explores 3 PTSD diagnoses that are frequently described in refugee populations and that have been observed in our clinical practices: complex PTSD, PTSD with psychotic symptoms, and PTSD with somatic symptoms.

RESULTS

While complex PTSD does not seem to be related to individuals' culture and origin, the other 2 diagnoses have been specifically described in refugee populations. PTSD with somatic manifestations appears to be the most frequently described and commonly acknowledged form in refugee populations, whereas PTSD with psychotic symptoms remains more controversial due to its clinical variability and association with comorbid disorders.

CONCLUSIONS

The difficulty of identifying PTSD with psychotic symptoms and PTSD with somatic symptoms in refugee populations may lead to misdiagnosis and explain the moderate effectiveness of care delivered to these populations. Appropriate diagnosis is essential to provide optimal psychiatric care to refugee populations.

Platelet serotonin concentration and trait aggression in veterans with post-traumatic stress disorder: a preliminary study

Animal and human studies suggest that aggressive behavior may be modulated by brain serotonergic system. Serotonergic (5-HT) dysfunction is associated with post-traumatic stress disorder (PTSD), but also with increased aggression and impulsivity, hallmarks of PTSD. The aim of the study was to investigate the association of platelet 5-HT concentration and various types of aggression and impulsivity in veterans with PTSD. A group of 42 male combat-related PTSD subjects entered the study. Four different aggression facets were measured by the Buss and Perry's Aggression Questionnaire (BPAQ). Verbal and physical types of impulsive aggressive behavior were measured by the subscales of the Žužul's Aggressiveness Inventory A-87. Impulsivity was determined using Eysenck's IVE questionnaire. PTSD severity was evaluated by Watson's PTSD questionnaire. Platelet serotonin concentration was determined spectrofluorimetrically. Confounding variables were: age, body mass, alcohol use, comorbid depression, and tobacco use. Platelet 5-HT concentration and PTSD severity were independently associated only with impulsive types of aggression, as higher platelet 5-HT concentration and more severe PTSD were related to more impulsive aggression. These results strongly recommend distinguishing between specific types of aggression facets, and advise the importance of theory-based concepts of aggression facets when evaluating the biological correlates of aggression.

Associations of neural processing of reward with posttraumatic stress disorder and secondary psychotic symptoms in trauma-affected refugees

Background: Psychological traumatic experiences can lead to posttraumatic stress disorder (PTSD). Secondary psychotic symptoms are not common but may occur. Objectives: Since psychotic symptoms of schizophrenia have been related to aberrant reward processing in the striatum, using the same paradigm we investigate whether the same finding extends to psychotic and anhedonic symptoms in PTSD. Methods: A total of 70 male refugees: 18 PTSD patients with no secondary psychotic symptoms (PTSD-NSP), 21 PTSD patients with secondary psychotic symptoms (PTSD-SP), and 31 healthy controls (RHC) were interviewed and scanned with functional magnetic resonance imaging (fMRI) during a monetary incentive delay task. Using region of interest analysis of the prefrontal cortex and ventral striatum, we investigated reward-related activity. Results: Compared to RHC, participants with PTSD had decreased neural activity during monetary reward. Also, participants with PTSD-SP exhibited decreased activity in the associative striatum relative to participants with PTSD-NSP during processing of motivational reward anticipation which correlated with severity of psychotic symptoms. However, the difference between the two PTSD groups disappeared when PTSD severity and trauma exposure were accounted for. Conclusions: Anhedonia and secondary psychotic symptoms in PTSD are characterized by dysfunctional reward consumption and anticipation processing, respectively. The latter may reflect a mechanism by which abnormal reward signals in the basal ganglia facilitates psychotic symptoms across psychiatric conditions.

Metabolomic and glycomic findings in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a stressor-related disorder that develops in a subset of individuals exposed to a traumatic experience. Factors associated with vulnerability to PTSD are still not fully understood. PTSD is frequently comorbid with various psychiatric and somatic disorders, moderate response to treatment and remission rates. The term "theranostics" combines diagnosis, prognosis, and therapy and offers targeted therapy based on specific analyses. Theranostics, combined with novel techniques and approaches called "omics", which integrate genomics, transcriptomic, proteomics and metabolomics, might improve knowledge about biological underpinning of PTSD, and offer novel therapeutic strategies. The focus of this review is on metabolomic and glycomic data in PTSD. Metabolomics evaluates changes in the metabolome of an organism by exploring the set of small molecules (metabolites), while glycomics studies the glycome, a complete repertoire of glycan structures with their functional roles in biological systems. Both metabolome and glycome reflect the physiological and pathological conditions in individuals. Only a few studies evaluated metabolic and glycomic changes in patients with PTSD. The metabolomics studies in PTSD patients uncovered different metabolites that might be associated with psychopathological alterations in PTSD. The glycomics study in PTSD patients determined nine N-glycan structures and found accelerated and premature aging in traumatized subjects and subjects with PTSD based on a GlycoAge index. Therefore, further larger studies and replications are needed. Better understanding of the biological basis of PTSD, including metabolomic and glycomic data, and their integration with other "omics" approaches, might identify new molecular targets and might provide improved therapeutic approaches.

Posttraumatic stress disorder with secondary psychotic features (PTSD-SP): Diagnostic and treatment challenges

Trauma exposure leads to various psychiatric disorders including depression, anxiety, bipolar disorders, personality disorders, psychotic disorders, and trauma related disorders, especially posttraumatic stress disorder (PTSD). There are some overlapping symptoms of both PTSD and psychosis that make diagnosis challenging. Despite this overlap, the evidence of PTSD with comorbid psychosis as a distinct entity lies in the research showing biologic, genetic and treatment management differences between psychotic PTSD, non-psychotic PTSD, psychotic disorders and healthy controls. There is emerging evidence that PTSD with secondary psychotic features (PTSD-SP) might be a discrete entity of PTSD with known risk factors that increase its prevalence. This review has presented evidence for individuals with PTSD-SP being distinct in genetics and neurobiological factors. Individuals with PTSD and comorbid psychosis can benefit from evidence based psychotherapy (EBT). There is not enough evidence to recommend second generation antipsychotics (SGA) for PTSD-SP given that risperidone and quetiapine are the only SGAs studied in randomized controlled trials. Hence, developing an operational diagnostic criteria and treatment framework for clinical and research use is critical.

Post-traumatic stress disorder, resilience and vulnerability

Post-traumatic stress disorder (PTSD), recognised as a diagnostic entity in 1980, was originally associated with combat or war experiences. It has since been recognised that it is prevalent in any population exposed to traumatic events. Although much has been written about the management of PTSD, the concepts of resilience and vulnerability have not received the same attention. This article reviews the conceptualisation, epidemiology and comorbidities of PTSD and highlights the factors underlying vulnerability and conveying resilience.

No association between the serotonin transporter linked polymorphic region polymorphism and severity of posttraumatic stress disorder symptoms in combat veterans with or without comorbid depression

Since both posttraumatic stress disorder (PTSD) and depression are associated with disturbances in the serotoninergic system, the aim of the study was to determine the association between severity of PTSD symptoms, serotonin transporter polymorphism (5-HTTLPR) and platelet serotonin (5-HT) concentration, in male combat veterans with PTSD (n = 325), who were subdivided according to presence of comorbid depression. The methodological approach included the psychiatric diagnostic interviews and rating scales (SCID for DSM-IV, HDRS, CAPS), polymerase chain reaction for 5-HTTLPR genotyping and spectrophotofluorometric method for measuring the platelet 5-HT concentration. PTSD veterans without depression had more severe PTSD symptoms, and less severe depressive symptoms, than PTSD veterans with depression. 5-HTTLPR genotype frequencies did not differ between veterans with mild, moderate and severe PTSD symptoms, and between depressed and non-depressed PTSD veterans. No significant association was found between the severity of PTSD symptoms and 5-HTTLPR genotype. Platelet 5-HT concentration was similar in PTSD veterans, with or without comorbid depression, and between two groups subdivided according to the severity of PTSD symptoms or 5-HTTLPR genotype. The study confirmed, on ethnically homogenous groups of veterans with matched combat experience, a lack of association between the PTSD symptoms severity and 5-HTTLPR or platelet 5-HT concentration.

Peripheral Biomarker Candidates of Posttraumatic Stress Disorder

There is high variability in the manifestation of physical and mental health problems following exposure to trauma and disaster. Although most people may show a range of acute symptoms in the aftermath of traumatic events, chronic and persistent mental disorders may not be developed in all individuals who were exposed to traumatic events. The most common long-term pathological consequence after trauma exposure is posttraumatic stress disorder (PTSD). However, comorbid conditions including depression, anxiety disorder, substance use-related problems, and a variety of other symptoms may frequently be observed in individuals with trauma exposure. Post-traumatic syndrome (PTS) is defined collectively as vast psychosocial problems that could be experienced in response to traumatic events. It is important to predict who will continue to suffer from physical and mental health problems and who will recover following trauma exposure. However, given the heterogeneity and variability in symptom manifestations, it is difficult to find identify biomarkers which predict the development of PTSD. In this review, we will summarize the results of recent studies with regard to putative biomarkers of PTSD and suggest future research directions for biomarker discovery for PTSD.

Influence of mental stress on platelet bioactivity

It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to represent a possible link in this respect. The anculeated platelets are the smallest corpuscular elements circulating in the human blood. They display different serotonergic markers which seem to reflect the central nervous serotonin metabolism. They are known as main effectors in haematological processes but recent research highlights their role in the innate and adaptive immune system. Platelets are containing a multitude of pro-inflammatory and immune-modulatory bioactive compounds in their granules and are expressing immune-competent surface markers. Research gives hint that platelets activation and reactivity is increased by mental stress. This leads to enhanced cross talk with the immune system via paracrine secretion, receptor interaction and formation of platelet leucocyte-aggregates. Recently it has been demonstrated that the immune system can have a remarkable impact in the development of psychiatric disorders. Therefore platelets represent an interesting research area in psychiatry and their role as a possible biomarker has been investigated. We review the influence of mental stress on what is termed platelet bioactivity in this article, which subsumes the mainly immune-modulatory activity of platelets in healthy volunteers, elderly persons with chronic care-giving strain, patients with cardiovascular diseases who are prone to psychosocial stress, as well as in patients with posttraumatic stress disorder. Research data suggest that stress enhances platelet activity, reactivity and immune-modulatory capacities.

The association between brain-derived neurotrophic factor Val66Met variants and psychotic symptoms in posttraumatic stress disorder

OBJECTIVES

Psychotic symptoms frequently occur in veterans with combat-related posttraumatic stress disorder (PTSD). Brain-derived neurotrophic factor (BDNF) plays a major role in neurodevelopment, neuro-regeneration, neurotransmission, learning, regulation of mood and stress responses. The Met allele of the functional polymorphism, BDNF Val66Met, is associated with psychotic disorders. This study intended to assess whether the Met allele is overrepresented in unrelated Caucasian male veterans with psychotic PTSD compared to veteran controls.

METHODS

The BDNF Val66Met variants were genotyped in 576 veterans: 206 veterans without PTSD and 370 veterans with PTSD subdivided into groups with or without psychotic features.

RESULTS

Veterans with psychotic PTSD were more frequently carriers of one or two Met alleles of the BDNF Val66Met polymorphism than veterans with PTSD without psychotic features and veterans without PTSD.

CONCLUSIONS

The study shows that veterans with psychotic PTSD carried more Met alleles of the BDNF Val66Met than non-psychotic veterans with PTSD or veterans without PTSD. The results might add further support to the hypothesis that psychotic PTSD is a more severe subtype of PTSD.

P11: a potential biomarker for posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a chronic and disabling anxiety disorder that occurs after a traumatic event. It is associated with an increased risk of suicide and marked deficits in social and occupational functioning. Currently, the diagnosis for PTSD is established on the basis of a patient's clinical history, mental status examination, duration of symptoms, and clinician administered symptom checklist or patient self-report. However, there are no available laboratory biomarker tests for PTSD. To begin intervention at the earliest possible time, priority must be given to developing objective approaches to determine the presence of PTSD. Thus, using cutting-edge technology and skill to develop a simple blood test or a biomarker to detect PTSD at its earliest and most treatable stage would benefit both physician and patient. Several technologies and skills have been used in the identification biomarker research. We discuss three major methods in this chapter (blood RNA and DNA purification, chromatin immunoprecipitation, and Western blot), which have been used in our study to determine whether p11 is a potential biomarker for PTSD. Using these procedures will not only enhance the study of the molecular mechanisms of PTSD but also help the translation of basic science to a clinical setting.

Suicide attempt, smoking, comorbid depression, and platelet serotonin in alcohol dependence

The risk of suicide in patients with alcoholism increases if alcoholism is related to comorbid depression. Both alcoholism and suicidal behavior are associated with reduced serotonin (5-hydroxytryptamine [5-HT]) function. Because suicide is enormous public health problem worldwide, to prevent suicide attempts, it is important to find peripheral marker of suicidal behavior. The aim of this study was to assess whether platelet 5-HT concentration is altered in alcoholic patients with or without suicide attempt. Platelet 5-HT concentration was evaluated in 397 male and 108 female ethnically homogenous medication-free patients with alcoholism, subdivided according to smoking status, comorbid depression, and a history of suicide attempt and in 450 male and 139 female healthy control (nonsuicidal) subjects. Suicide attempt was assessed by two measures: according to the score 4 on the item 3 from the Hamilton Rating Scale for Depression and according to the Structured Clinical Interview regarding suicidal attempt during lifetime. Both male and female patients with alcoholism who were nonsmokers had significantly lower platelet 5-HT concentration than the corresponding healthy subjects. Multifactor analyses of variance revealed the significant effects of alcoholism and smoking, but the lack of significant effects of suicide attempt, sex, or comorbid depression, and no interactions between variables, on platelet 5-HT concentration. Platelet 5-HT concentration did not differ significantly between suicidal patients compared with nonsuicidal patients with alcoholism. Because the results from the present study showed similar platelet 5-HT values between patients with or without a history of suicide attempt, our data did not support the hypothesis that platelet 5-HT concentration might be used as a peripheral marker of the pronounced suicidal behavior in alcoholism.

A meta-analytic investigation of the structure of posttraumatic stress disorder symptoms

Converging lines of evidence have called into question the validity of conceptualizations of posttraumatic stress disorder (PTSD) based on the Diagnostic and Statistical Manual of Mental Disorders (DSM; American Psychiatric Association, 2000) and suggested alternative structural models of PTSD symptomatology. We conducted a meta-analysis of 40 PTSD studies (N = 14,827 participants across studies) that used a DSM-based measure to assess PTSD severity. We aggregated correlation matrices across studies and then applied confirmatory factor analysis to the aggregated matrices to test the fit of competing models of PTSD symptomatology that have gained support in the literature. Results indicated that both prominent 4-factor models of PTSD symptomatology yielded good model fit across subsamples of studies; however, the model comprising Intrusions, Avoidance, Hyperarousal, and Dysphoria factors appeared to fit better across studies. Results also indicated that the best fitting models were not moderated by measure or sample type. Results are discussed in the context of structural models of PTSD and implications for the diagnostic nosology.

Platelet serotonin concentration and monoamine oxidase type B activity in female patients in early, middle and late phase of Alzheimer's disease

Alzheimer's disease (AD) is a progressive, neurodegenerative disorder with unclear aetiology. Cognitive impairment in AD might be associated with altered serotonergic system. The aim of the study was to determine platelet serotonin (5-HT) concentrations and platelet monoamine oxidase type B (MAO-B) activity in patients with different severity of AD. Platelet 5-HT concentrations and MAO-B activity were determined spectrofluorimetrically in 74 female patients with AD (NINCDS-ADRDA, DSM-IV-TR criteria), subdivided according to the Mini Mental State Examination (MMSE) scores in three groups with a) 23 patients in early (MMSE scores 19-24), b) 23 patients in middle (MMSE 10-18), and c) 28 patients in late (MMSE 0-9) phase of AD, and in 49 age-matched healthy women. Platelet 5-HT concentrations and MAO-B activity were similar between all patients with AD and healthy subjects, but were significantly lower in patients in the late phase of AD than in other phases of AD, and in healthy controls. The significant correlations were found between MMSE scores and platelet 5-HT concentrations, MAO-B activity and age. Lower platelet 5-HT concentration and MAO-B activity in the late phase of AD suggested that these markers might indicate severity and/or clinical progress of AD.

Validity of 'post-traumatic stress disorder with secondary psychotic features': a review of the evidence

OBJECTIVE

To review the evidence from empirical studies regarding the validity of 'post-traumatic stress disorder with secondary psychotic features' (PTSD-SP) as a separate diagnostic entity.

METHOD

The authors performed a review tracing publications between 1980 and January 2008.

RESULTS

Twenty-four comparative studies were included. These studies indicate that PTSD-SP is a syndrome that comprises PTSD-symptoms followed in time by the additional appearance of psychotic features. The psychotic features are not confined to episodes of re-experiencing, but remain present continuously. PTSD-SP seems to have some biological features differentiating it from schizophrenia and PTSD, e.g. there are differences in smooth pursuit eye movement patterns, concentrations of corticotropin-releasing factor and dopamine beta-hydroxylase activity.

CONCLUSION

There is currently not yet full support for PTSD-SP as a nosological entity. However, the delineation of PTSD-SP from other psychiatric syndromes is notable and biological studies seem to support the validity as a separate diagnostic entity.

Platelet serotonin concentration and suicidal behavior in combat related posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a serious and global problem, a psychiatric disorder that frequently occurs with different comorbidities, and is associated with a high suicide rate. Pathophysiologically, both PTSD and suicidal behavior are related to disturbances in the central serotonergic system. Serotonin (5-hydroxytryptamine, 5-HT) controls emotional behavior, anxiety, impulsivity and aggression, and nearly all known antidepressants and antianxiety drugs affect 5-HT transmission. Platelet 5-HT can be used as a limited peripheral marker of the central serotonergic synaptosomes, since it is related to particular basic psychopathological characteristics of several psychiatric disorders. Platelet 5-HT concentration has been reported to be similar in PTSD subjects and healthy controls, but suicidal patients across different psychiatric diagnoses have reduced platelet 5-HT concentration. This study examined platelet 5-HT concentration by the spectrofluorimetric method in male subjects: 73 suicidal and 47 non-suicidal veterans with current and chronic combat related PTSD, 45 suicidal and 30 non-suicidal comparative non-PTSD subjects and 147 healthy men. The presence of suicidal behavior (score=0, non-suicidal; scores > or =1, suicidal) was assessed with the Hamilton Depression Rating Scale-17 (HDRS). Platelet 5-HT concentration was significantly lower in suicidal PTSD and non-PTSD patients compared to non-suicidal patients or healthy controls. Since the majority of patients scored very low on item 3 of HDRS, no significant correlation between suicidal scores and platelet 5-HT concentration was found. These results show that reduced platelet 5-HT concentration is related to suicidal behavior in PTSD, and suggest that platelet 5-HT concentration might be used as a peripheral marker to predict suicidal behavior across psychiatric diagnoses.

Monoamine oxidase (MAO) intron 13 polymorphism and platelet MAO-B activity in combat-related posttraumatic stress disorder

BACKGROUND

The neurobiology of posttraumatic stress disorder (PTSD) involves alterations in multiple neuroendocrine and neurotransmitter systems. Platelet monoamine oxidase (MAO-B) has been associated with susceptibility to various psychiatric disorders, personality traits and behaviors.

METHODS

Platelet MAO-B activity and MAO-B intron 13 polymorphism (a G/A substitution) were determined in male war veterans (n=106) with DSM-IV diagnosed current and chronic PTSD, divided into subgroups of PTSD patients with (n=28) or without (n=78) psychotic features, combat exposed veterans (n=41) who did not develop PTSD, and healthy control men (n=242).

RESULTS

Two-way ANOVAs revealed a significant effect of diagnosis and smoking, a significant effect of smoking, no significant effect of genotype, and no significant interaction between genotype, smoking or diagnosis, on platelet MAO-B activity. One-way ANOVAs showed significantly lower platelet MAO-B activity in smokers than in nonsmokers. After controlling for smoking, veterans with psychotic PTSD had significantly higher platelet MAO-B activity than veterans with or without PTSD, or healthy subjects.

LIMITATIONS

The results were obtained on peripheral biochemical marker, i.e. platelet MAO activity.

CONCLUSIONS

The MAO-B intron 13 polymorphism was not functional, and did not affect platelet MAO-B activity. The allele frequencies of the MAO-B genotype were similarly distributed among healthy controls and veterans with or without PTSD and/or psychotic symptoms. The results suggest that platelet MAO-B activity, controlled for smoking status, might be used as a peripheral marker of the psychotic symptoms in PTSD.

Platelet serotonin and serum lipids in psychotic mania

BACKGROUND

The role of serotonergic system and lipid status in the etiology of mania and its subtypes is not clear. The aims of the study were to determine platelet serotonin (5-HT) concentration, platelet monoamine oxidase (MAO) activity, and serum total cholesterol, high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL) and triglycerides (TG) in patients with psychotic and nonpsychotic subtypes of mania and in healthy control subjects.

METHODS

The serum lipids, platelet 5-HT and MAO were determined in 40 (17 psychotic, 23 nonpsychotic) drug free male inpatients with type I bipolar affective disorder, current episode mania (DSM-IV criteria), and in 32 healthy male subjects.

RESULTS

Platelet 5-HT levels in manic patients were similar to the values in healthy controls. Serum cholesterol and LDL values were significantly lower in manic patients than in healthy controls. Patients with psychotic features had increased platelet 5-HT concentrations and decreased levels of cholesterol and LDL as compared to the nonpsychotic manic patients and healthy controls. There was no significant difference in age, body mass index, platelet MAO activity, serum levels of TG and HDL between psychotic and nonpsychotic manic patients and healthy subjects.

LIMITATION

Data on physical activity, dietary habits and alcohol consumption before hospitalization were not collected.

CONCLUSION

The results of the present study suggest that biological differences between subtypes of mania might depend upon the presence of the psychotic symptoms. Our data confirm our previous results showing the increased platelet 5-HT concentration in psychotic disorders across the different diagnoses.