The role of nociceptive input and tissue injury on stress regulation in borderline personality disorder

Depression with comorbid borderline personality disorder - could ketamine be a treatment catalyst?

Borderline personality disorder (BPD) is diagnosed in 10-30% of patients with major depressive disorder (MDD), and the frequency of MDD among individuals with BPD reaches over 80%. The comorbidity of MDD and BPD is associated with more severe depressive symptoms and functional impairment, higher risk of treatment resistance and increased suicidality. The effectiveness of ketamine usage in treatment resistant depression (TRD) has been demonstrated in numerous studies. In most of these studies, individuals with BPD were not excluded, thus given the high co-occurrence of these disorders, it is possible that the beneficial effects of ketamine also extend to the subpopulation with comorbid TRD and BPD. However, no protocols were developed that would account for comorbidity. Moreover, psychotherapeutic interventions, which may be crucial for achieving a lasting therapeutic effect in TRD and BPD comorbidity, were not included. In the article, we discuss the results of a small number of existing studies and case reports on the use of ketamine in depressive disorders with comorbid BPD. We elucidate how, at the molecular and brain network levels, ketamine can impact the neurobiology and symptoms of BPD. Furthermore, we explore whether ketamine-induced neuroplasticity, augmented by psychotherapy, could be of use in alleviating core BPD-related symptoms such as emotional dysregulation, self-identity disturbances and self-harming behaviors. We also discuss the potential of ketamine-assisted psychotherapy (KAP) in BPD treatment. As there is no standard approach to the application of ketamine or KAP in individuals with comorbid TRD and BPD, we consider further research in the field as imperative. The priorities should include development of dedicated protocols, distinguishing subpopulations that may benefit most from such treatment and investigating factors that may influence its effectiveness and safety.

Physiological response to pain in female adolescents with nonsuicidal self-injury as a function of severity

BACKGROUND

Preliminary evidence indicates altered hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) response to experimental pain in individuals with nonsuicidal self-injury (NSSI). This study investigated effects of NSSI severity and severity of psychopathology on the HPA axis and ANS response to pain.

METHODS

N = 164 adolescents with NSSI and n = 45 healthy controls received heat pain stimulation. Salivary cortisol, α-amylase and blood pressure were repeatedly assessed before and after painful stimulation. Heart rate (HR) and heart rate variability (HRV) were assessed continuously. NSSI severity and comorbid psychopathology were derived from diagnostic assessments. Main and interaction effects of time of measurement and NSSI severity, adjusted for severity of adverse childhood experiences, borderline personality disorder and depression, on HPA axis and ANS response to pain were examined using regression analyses.

RESULTS

Increasing NSSI severity predicted an increasing cortisol response (χ2(3) = 12.09, p = .007) to pain. After adjusting for comorbid psychopathology, greater NSSI severity predicted decreased α-amylase levels following pain (χ2(3) = 10.47, p = .015), and decreased HR (χ2(2) = 8.53, p = .014) and increased HRV(χ2(2) = 13.43, p = .001) response to pain.

LIMITATIONS

Future research should implement several NSSI severity indicators, potentially revealing complex associations with the physiological response to pain. Assessing physiological responses to pain in NSSI in a naturalistic setting presents a promising avenue for future research in NSI.

CONCLUSIONS

Findings indicate an increased pain-related HPA axis response and an ANS response characterized by reduced sympathetic and increased parasympathetic activity associated with NSSI severity. Results support claims for dimensional approaches to NSSI and its related psychopathology alongside shared, underlying neurobiological correlates.

Stress-induced alterations in resting-state functional connectivity among adolescents with non-suicidal self-injury

BACKGROUND

Non-suicidal self-injury (NSSI) is a major mental health problem among youth worldwide. Dysfunction in emotion regulation contributes to NSSI, but research on the underlying neurobiological mechanisms of NSSI is limited. Adolescents with emotion regulation difficulties are vulnerable to stress, making them susceptible to maladaptive coping mechanisms such as NSSI.

METHODS

This study examined the functional neurocircuitry relevant to emotion regulation and stress coping in individuals with NSSI compared with healthy controls. This case-control study included 34 adolescents with NSSI (15.91 years) and 28 (16.0 years) unaffected controls. Participants underwent a functional magnetic resonance imaging scan before and after completing a laboratory stress-induction paradigm (the Montreal Imaging Stress Test). The effects of stress induction were quantified by both physiological measures and self-reports.

RESULTS

Participants with NSSI showed distinctive alterations in functional resting-state following stress induction, which differentiated them from unaffected controls. Results show a reduction in functional connectivity between frontoparietal regions and the angular gyrus within the patient group compared to controls, as well as an increase in functional connectivity between visual regions, the insular cortex, the planum polare, and the central opercular cortex. After conditions of acute stress, adolescents with NSSI show changes in functional connectivity of regions associated with sensorimotor alertness, attention, and effortful emotion regulation.

LIMITATIONS

The patient group showed both NSSI and suicidal behavior, therefore results might be partly due to suicidality.

CONCLUSION

The findings emphasize the importance of targeting emotion regulation within therapeutic approaches to enhance stress coping capacity, which in turn may contribute to counteracting self-injurious behavior.

Cerebral processing of sharp mechanical pain measured with arterial spin labeling

INTRODUCTION

Arterial spin labeling (ASL) is a functional neuroimaging technique that has been frequently used to investigate acute pain states. A major advantage of ASL as opposed to blood-oxygen-level-dependent functional neuroimaging is its applicability for low-frequency designs. As such, ASL represents an interesting option for studies in which repeating an experimental event would reduce its ecological validity. Whereas most ASL pain studies so far have used thermal stimuli, to our knowledge, no ASL study so far has investigated pain responses to sharp mechanical pain.

METHODS

As a proof of concept, we investigated whether ASL has the sensitivity to detect brain activation within core areas of the nociceptive network in healthy controls following a single stimulation block based on 96 s of mechanical painful stimulation using a blunt blade.

RESULTS

We found significant increases in perfusion across many regions of the nociceptive network such as primary and secondary somatosensory cortices, premotor cortex, posterior insula, inferior parietal cortex, parietal operculum, temporal gyrus, temporo-occipital lobe, putamen, and the cerebellum. Contrary to our hypothesis, we did not find any significant increase within ACC, thalamus, or PFC. Moreover, we were able to detect a significant positive correlation between pain intensity ratings and pain-induced perfusion increase in the posterior insula.

CONCLUSION

We demonstrate that ASL is suited to investigate acute pain in a single event paradigm, although to detect activation within some regions of the nociceptive network, the sensitivity of our paradigm seemed to be limited. Regarding the posterior insula, our paradigm was sensitive enough to detect a correlation between pain intensity ratings and pain-induced perfusion increase. Previous experimental pain studies have proposed that intensity coding in this region may be restricted to thermal stimulation. Our result demonstrates that the posterior insula encodes intensity information for mechanical stimuli as well.

Adolescents with borderline personality disorder show a higher response to stress but a lack of self-perception: Evidence through affective computing

Stress reactivity is a complex phenomenon associated with multiple and multimodal expressions and functions. Herein, we hypothesized that compared with healthy controls (HCs), adolescents with borderline personality disorder (BPD) would exhibit a stronger response to stressors and a deficit in self-perception of stress due to their lack of insight. Twenty adolescents with BPD and 20 matched HCs performed a socially evaluated mental arithmetic test to induce stress. We assessed self- and heteroperception using both human ratings and affective computing-based methods for the automatic extraction of 39 behavioral features (2D + 3D video recording) and 62 physiological features (Nexus-10 recording). Predictions were made using machine learning. In addition, salivary cortisol was measured. Human ratings showed that adolescents with BPD experienced more stress than HCs. Human ratings and automated machine learning indicated opposite results regarding self- and heteroperceived stress in adolescents with BPD compared to HCs. Adolescents with BPD had higher levels of heteroperceived stress than self-perceived stress. Similarly, affective computing achieved better classification for heteroperceived stress. HCs had an opposite profile; they had higher levels of self-perceived stress, and affective computing reached a better classification for self-perceived stress. We conclude that adolescents with BPD are more sensitive to stress and show a lack of self-perception (or insight). In terms of clinical implications, our affective computing measures may help distinguish hetero- vs. self-perceptions of stress in natural settings and may offer external feedback during therapeutic interaction.

Advancing a temporal framework for understanding the biology of nonsuicidal self- injury: An expert review

Nonsuicidal self-injury (NSSI) is a serious clinical problem, particularly for adolescents and young adults. NSSI is a complex behavior that emerges through the intersecting effects of social, psychological, and biological mechanisms. Although the social and psychological contributions to risk for developing NSSI are relatively well understood and have guided the development of effective psychosocial treatments for self-injury, the biological mechanisms underlying NSSI have just begun to come to light. To evaluate and categorize the biological research conducted on the topic of NSSI, we propose a model that distinguishes between trait and state markers. According to this model, risk factors and mechanisms involved in NSSI can be distinguished into both trait and state factors. We review the existing evidence on distal biological traits (predictors) of NSSI, proximal biological traits (correlates) of NSSI, and biological states directly preceding or following NSSI. We conclude by providing recommendations for future research on the neurobiology of NSSI.

Borderline personality disorder

Borderline personality disorder (BPD) is a mental disorder with a high burden on patients, family members, and health-care systems. The condition was previously regarded as untreatable, but progress in understanding and management has resulted in earlier diagnosis and better treatment outcomes. A coherent syndrome of BPD typically onsets during adolescence (after age 12 years). BPD is often preceded by or co-develops with symptoms of internalising disorders (depression and anxiety), externalising disorders (conduct problems, hyperactivity, and substance use), or both. BPD is associated with various poor outcomes, including low occupational and educational attainment, lack of long-term relationships, increased partner conflict, sexual risk-taking, low levels of social support, low life satisfaction, and increased service use. Psychotherapy is the main treatment for BPD; drug treatment is only indicated for comorbid conditions that require medication, or during a crisis if psychosocial interventions are insufficient. Awareness of BPD by non-specialists, as well as specialists, is key to appropriate early intervention.

Enhanced pain modulation capacity among individuals with borderline personality disorder: A possible mechanism underlying their hypoalgesia

BACKGROUND

Ample evidence suggests that individuals with borderline personality disorder (BPD) exhibit hyposensitivity to pain. Since the underlying mechanism of the pain hyposensitivity is unknown, we tested here for the first time whether this hyposensitivity is pain specific or exists also for innocuous sensation, and whether it is associated with enhanced descending pain modulation capabilities.

METHODS

Participants were 55 women; 22 patients with BPD and 33 matched healthy controls. Testing included the measurement of warmth sensation threshold (WST), heat-pain threshold (HPT), pain adaptation, conditioned pain modulation (CPM) and temporal summation of heat-pain (TSP). The level of dissociation was also evaluated.

RESULTS

Women with BPD had higher WST and HPT compared with healthy controls. Moreover, women with BPD had greater magnitude of pain adaptation and CPM as well as higher dissociation level compared to controls. In neither the BPD nor the control group did WST and HPT correlate with pain adaptation, CPM or dissociation. In the BPD group only, HPT inversely correlated with the magnitude of TSP.

CONCLUSIONS

Women with BPD present generalized hyposensitivity to both innocuous and noxious stimuli. Furthermore, women with BPD exhibit more efficient pain inhibition capabilities than healthy controls. While efficient pain modulation may underlie pain hyposensitivity in BPD, both traits may exist independently from each other, or may be moderated by another factor such as dissociation.

SIGNIFICANCE

On the basis of testing pronociceptive and antinociceptive components among individuals with BPD and healthy controls, this study reveals enhanced ability to inhibit pain among woman with borderline personality disorder (BPD) which may underlie hyposensitivity to both noxious and innocuous stimuli and perhaps also self-injurious behaviour among these individuals. The study contributes novel information on possible mechanisms involved in BPD manifestations.

The glutamate to γ-aminobutyric acid ratio in the posterior insula is associated with pain perception in healthy women but not in women with borderline personality disorder

This study aimed to investigate whether the differences in pain perception between patients with borderline personality disorder (BPD) and healthy subjects (HCs) can be explained by differences in the glutamate/GABA ratio in the posterior insula. In total, 29 BPD patients and 31 HCs were included in the statistical analysis. Mechanical pain sensitivity was experimentally assessed with pinprick stimuli between 32 and 512 mN on a numeric rating scale. The metabolites were measured in the right posterior insula using the MEshcher-GArwood Point-RESolved Spectroscopy sequence for single-voxel magnetic resonance spectroscopy (1H-MRS). The 256- and the 512-mN pinprick stimuli were perceived as significantly less painful by the BPD patient group compared with HCs. No differences were found between groups for the glutamate/GABA ratios. A positive correlation between the glutamate/GABA ratio and the pain intensity ratings to 256- and 512-mN pinpricks could be found in the combined and in the HC group. In the BPD patient group, the correlations between the glutamate/GABA ratio and the pain intensity ratings to 256- and 512-mN pinpricks did not reach significance. In conclusion, the study showed that individual differences in pain perception may in part be explained by the individual glutamate/GABA ratio in the posterior insula. However, this possible mechanism does not explain the differences in pain perception between BPD patients and HCs.

Effects of a Painful Stimulus on Stress Regulation in Male Patients With Borderline Personality Disorder: A Pilot Study

Pain processing in relation to stress has so far not been investigated in male patients with borderline personality disorder (BPD). This experimental pilot study examined 17 male BPD patients and 20 male healthy controls (HCs) to assess the effects of a pain stimulus on arousal, aggression, pain (ratings), and heart rate. At baseline, BPD patients showed significantly higher arousal and aggression; however, there was no significant difference in heart rate compared to the HC group. Following stress induction, a noninvasive mechanical pain stimulus was applied. No significant differences in pain ratings or heart rates were found between the groups. For arousal, a significantly stronger decrease was revealed in the BPD group compared to the HC group (t = 2.16, p = .038). Concerning aggression, the BPD group showed a significantly greater decrease after the pain stimulus than the HC group (t = 3.25, p = .002). This data showed that nonsuicidal self-injury can reduce arousal and aggression in male BPD.

Differential perception of sharp pain in patients with borderline personality disorder

BACKGROUND

Cutting is the most common method of non-suicidal self-injury (NSSI) to reduce inner tension in patients with Borderline Personality Disorder (BPD). Aim of this study was to compare pain perception induced by an incision and by application of a surrogate model for sharp mechanical pain (a non-invasive "blade") in BPD.

METHODS

22 female patients and 20 healthy controls (HC) received a small incision into the volar forearm, a 7s-blade application on the same side, and non-invasive phasic stimuli (pinprick, blade, laser, tactile). Pain intensity as well as affective versus sensory components were assessed.

RESULTS

Incision was rated similarly by both groups (BPD: 28.6 ± 5.5 vs. HC: 33.9 ± 6.6; mean maximum pain ± SEM; p > 0.8), without significant difference for "7-s-blade" (BPD: 18.1 ± 3.8 vs. HC: 25.3 ± 3.6; mean maximum pain ± SEM; p > 0.17) or between "7-s-blade" and incision (BPD: p > 0.12; HC: p > 0.84). However, patients' intensity ratings returned significantly faster to baseline after incision (BPD: 38.9 ± 12.6 s vs. HC: 74.52 ± 11.5 s; p < 0.05), and patients evaluated "blade" and incision without any affective and with different sensory descriptors, indicating an altered evaluation of NSSI-like stimulation with qualitative in addition to quantitative differences-especially for the sharp pain component.

CONCLUSIONS

The reduced perception of suprathreshold nociceptive stimuli is based on a missing affective component and specific loss of the perception of "sharpness" as part of the sensory component of pain. The results further demonstrate the usefulness of the "blade" for the perception of sharpness in patients.

SIGNIFICANCE

Patients with Borderline Personality Disorder (BPD) who engage in non-suicidal self-injury (NSSI) report less pain in response to phasic nociceptive stimuli. In comparing an invasive pain stimulus to phasic nociceptive stimuli in BPD patients, the "blade" as non-invasive surrogate model for sharp mechanical pain in psychiatric patients is used. In contrast to healthy volunteers, BPD patients do not report significant affective ratings and specifically display a reduced sensory component for sharpness.

Physical pain recruits the nucleus accumbens during social distress in borderline personality disorder

Patients with borderline personality disorder (BPD) often engage in dangerous self-injurious behaviors (SIBs) as a maladaptive technique to decrease heightened feelings of distress (e.g. negative feelings caused by social exclusion). The reward system has recently been proposed as a plausible neural substrate, which may influence the interaction between social distress and physical pain processing in patients that engage in SIBs. Using functional magnetic resonance imaging (fMRI) in 20 adult BPD patients with a history of SIBs and 23 healthy controls (HCs), we found a hyper-activation of the nucleus accumbens (NAcc) and amygdala when painful stimuli were presented to BPD patients (but not HCs) in a state of heightened distress, induced via social exclusion. This differential NAcc activity was mediated by anxious attachment style, which is a key developmental feature of the disorder. Altogether, these results suggest a neural mechanism underlying the pathophysiology of SIBs in these patients, which is likely reinforced via the reward system.

Borderline personality disorder

Caretakers are often intimidated or alienated by patients with borderline personality disorder (BPD), compounding the clinical challenges posed by the severe morbidity, high social costs and substantial prevalence of this disorder in many health-care settings. BPD is found in ∼1.7% of the general population but in 15-28% of patients in psychiatric clinics or hospitals and in a large proportion of individuals seeking help for psychological problems in general health facilities. BPD is characterized by extreme sensitivity to perceived interpersonal slights, an unstable sense of self, intense and volatile emotionality and impulsive behaviours that are often self-destructive. Most patients gradually enter symptomatic remission, and their rate of remission can be accelerated by evidence-based psychosocial treatments. Although self-harming behaviours and proneness to crisis can decrease over time, the natural course and otherwise effective treatments of BPD usually leave many patients with persistent and severe social disabilities related to depression or self-harming behaviours. Thus, clinicians need to actively enquire about the central issues of interpersonal relations and unstable identity. Failure to correctly diagnose patients with BPD leads to misleading pharmacological interventions that rarely succeed. Whether the definition of BPD should change is under debate that is linked to not fully knowing the nature of this disorder.

Stress reactivity and pain-mediated stress regulation in remitted patients with borderline personality disorder

Objective

Patients with borderline personality disorder (BPD) use nonsuicidal self-injury (NSSI) to cope with states of elevated inner tension. It is unclear to what extent remitted BPD patients experience these states and whether the experience of pain still regulates emotion. The purpose of this study was the investigation of baseline stress levels, stress reactivity, and pain-mediated stress regulation in remitted BPD patients.

Method

Subjective and objective stress parameters were assessed in 30 remitted BPD patients, 30 current BPD patients, and 30 healthy controls. After stress induction, a non-nociceptive tactile stimulus, a tissue-injuring, or a noninvasive pain stimulus was applied to the right volar forearm.

Results

Baseline stress levels of remitted BPD patients lie in between the stress levels of current BPD patients and healthy controls. Urge for NSSI increased significantly more in current than remitted BPD patients. The experience of pain led to a greater decrease of arousal in current compared to remitted BPD patients and healthy controls.

Conclusions

States of increased tension still seem to appear in remitted BPD patients. The role of pain-mediated stress regulation appears to be reduced in remitted patients.

How Do Stress Exposure and Stress Regulation Relate to Borderline Personality Disorder?

Borderline personality disorder (BPD) is a severe and frequent disorder characterized by a pervasive pattern of instability affecting impulse control, emotional regulation, cognitive processing, self-image and interpersonal relationships. Patients’ personal histories are often marked by stressful or traumatic experiences, either unique or repeated. Moreover, while clinical signs of the disorder include both chronic and acute features, acute features are mostly triggered by acute stressful situations. Such features include transient cognitive distortion, intense anger, uncontrollable impulsivity, and self-harm behavior – including suicide – and contribute to the burden of the disease. In this paper, we review the various aspects (epidemiological, clinical, and physiological) contributing to the relationship between BDP and stress. In particular, we explore the statistical association between stress exposure and the emergence of BPD while taking into account other psychopathologies, such as post-traumatic stress disorder. Then, the different aspects of stress responses (namely, the phenomenological, behavioral, hormonal, neuro-vegetative and neural responses) are reviewed in BPD patients. Pathophysiological hypotheses are formulated to explain the differences in responses between BPD patients and healthy subjects and their relation to BPD symptoms. Although the pathogenesis remains uncertain, our conclusions seem to reflect a specific biological and neural pattern of altered stress perception and regulation in BPD.