Youth with chronic pain report higher rates of psychological trauma (abuse, neglect, violent or conflictual home environment, etc.) when compared to the average population or healthy controls [1
]. In particular, functional abdominal pain disorders (FAPDs), which are common, persistent, and/or recurrent abdominal pain conditions without a clear organic etiology, are worthy of further investigation in relation to trauma. In fact, a history of traumatic events and/or life stressors may lead to the development of persistent abdominal pain in a subset of youth [3
]. A significant subset of youth with FAPDs also report a high rate of functional disability (e.g., minimizing physical activity) [5
] and psychological impairment (e.g., anxiety, depression [5
], somatic symptoms [9
], and distress [11
]) that may be related to the high rates of trauma experiences in this group [2
]. Despite this, the link between pediatric FAPDs, trauma, and other clinical indicators, such as functional impairment and treatment response, have not yet been investigated.
There is some evidence that the prevalence of FAPDs is significantly higher in adults who report psychological stress and a history of psychological trauma [8
]. However, minimal research has been carried out in pediatric populations. In a notable exception, a recent study performed in a large heterogenous sample of youth with chronic pain presenting for evaluation to a tertiary chronic pain clinic found 83% of youth (up to age 18) who presented with FAPDs reported at least one adverse childhood experience (ACE; e.g., abuse or neglect, parental separation or divorce, violent or conflictual home environment etc.) in their lifetime [2
]. Results of this same study indicated that youth with chronic pain (FAPDs and other conditions) and a history of ACEs reported higher rates of anxiety, depression, and fear of pain compared to youth with lower or no history of ACEs [2
]. In comparison, epidemiologic studies on trauma in youth indicates that rates can range from 8–12% (sexual assault) to 38–70% (witness to serious community violence) for single incident exposure with 20–48% of youth reporting multiple types of victimization [14
]. Evidence in pain populations specifically also suggests that youth with heterogenous forms of chronic pain and a history of trauma are more likely to report symptoms of posttraumatic stress disorder (PTSD; re-experiencing, impacted mood or cognitions, bad dreams about the event, hypervigilance, etc. [15
]) when compared to youth without chronic pain, [16
] and it has been proposed that PTSD may maintain chronic pain symptoms in youth [17
]. However, the rates of PTSD and its impact on functioning have not previously been examined in youth with FAPDs specifically. Nor is it understood how trauma impacts psychological treatment response in youth with chronic pain conditions like FAPDs. This lack of research in youth with FAPDs is striking, given that these are among the most commonly reported chronic pain conditions affecting youth [12
In general, the presence of psychological distress, such as anxiety or depression, has been shown to contribute to poorer psychosocial and physical treatment outcomes in youth with chronic pain conditions [18
]. A recent study in youth with chronic pain found trauma history did not negatively impact psychosocial or physical treatment outcomes among youth presenting for intensive (i.e., day treatment) pain-focused rehabilitation [20
]. However, this study was limited to participants enrolled in intensive pain rehabilitation who were required to “fail” (i.e., not show sufficient treatment response) traditional outpatient psychotherapy [21
]. No study to date has examined post-treatment psychosocial or physical functioning in youth with chronic pain and a history of trauma and/or PTSD in an outpatient setting. It is known that, irrespective of pain, youth with a history of trauma and/or PTSD require targeted psychosocial treatment approaches (e.g., trauma-focused cognitive behavioral therapy [23
]) and many fail to respond to traditional psychotherapies [25
]. Therefore, it may be that youth with trauma and/or PTSD and chronic pain are less likely to respond to traditional pain-focused outpatient psychotherapy and would thus benefit from a trauma-focused approach, but this remains unclear.
Aims of the current study included examining (1) the rates of PTSD in youth with FAPDs and (2) the association between PTSD and psychosocial (i.e., anxiety, depression, pain catastrophizing) and physical impairment (i.e., functional disability, pain intensity, somatization) in youth with FAPDs when compared to youth with FAPDs and no PTSD history. Further, we explored the association between PTSD diagnosis and post-treatment functioning (i.e., psychosocial and physical impairment) in youth with FAPDs enrolled in a short-term cognitive behavioral therapy to target pain and comorbid anxiety [26
]. To begin, it was hypothesized that a significantly higher rate of youth with FAPDs would meet diagnostic criteria for PTSD at baseline when compared to the average population. This is based on the high rate of ACE exposure in youth with FAPDs (up to 83%) [2
], comparatively lower rates of ACEs in general pediatric populations (37–67% [27
]), and the previous studies on rates of posttraumatic stress in pediatric pain populations (e.g., up to 32% report posttraumatic stress symptoms [non-diagnostic] [16
]) compared to general pediatric populations (ranging between 0.4% and 15.9% [28
]). Considering the association between PTSD and poorer psychosocial and physical impairment in adult and/or mixed chronic pain populations, it was also hypothesized that youth with FAPDs who meet criteria for PTSD would evidence poorer psychosocial and physical functioning at baseline when compared to youth with FAPDs and no PTSD. It was also hypothesized that PTSD would adversely affect the response to cognitive behavioral therapy (CBT) for pain and anxiety, when compared to youth with FAPDs and no PTSD diagnosis.
The current study aimed to examine the incidence of posttraumatic stress disorder (PTSD) and its association with physical and psychosocial functioning in youth with functional abdominal pain disorders (FAPDs). The findings are timely given the lack of research on rates of PTSD in pediatric FAPDs, and the extremely limited understanding of how PTSD relates to psychosocial and physical impairment in youth with FAPDs. Moreover, it is currently unknown how psychological intervention outcomes are affected for youth with chronic pain conditions such as FAPDs and PTSD. Therefore, an exploratory aim was also to examine outcomes for youth with FAPDs and PTSD vs. no PTSD who completed a brief pain and anxiety focused cognitive behavioral intervention (Aim to Decrease Anxiety and Pain Treatment (ADAPT)) [26
Results of the current study indicated that, when assessed via a gold-standard semi-structured clinical interview, 12.4% of youth with FAPDs meet diagnostic criteria for PTSD. On average, their symptoms were rated by the administering clinician as in the “severe” range. In non-pain pediatric populations, epidemiologic studies in youth (under 18) have reported incidence rates of PTSD as low as 0.4% overall, with rates higher in females (0.7%) vs. males (0.1%) [42
]. Conversely, a large meta-analysis of studies using a semi-structured interview revealed lifetime rates of PTSD in (non-pain) youth to be as high as 15.9% across both males and females [43
]. By comparison, a recent study examining rates of self-reported posttraumatic stress symptoms (PTSS) in a larger heterogenous pediatric pain population found that 32% of youth reported PTSS [16
]. Results of the current study are consistent with previous studies of PTSS in pediatric pain samples in that findings suggest PTSS/PTSD rates to be high when compared (with some estimates) to the average population. However, the disparate rates of PTSD/PTSS found across both pediatric pain and population sample studies may be due to the varying methods of screening or diagnostic procedures by study. For example, Noel, et al. utilized a self-report screening questionnaire (Child PTSD symptom checklist-5; CPSS-5 [44
]), whereas the current study utilized a semi-structured diagnostic interview by a trained clinician to query current diagnosis (ADIS [40
]). Both methods are important (e.g., self-report measures can certainly be more practical to administer) and provide a better idea of how these symptoms may manifest in pediatric pain populations, but the use of semi-structured interviews by a trained clinician are considered the gold standard for diagnostic (vs. symptom) assessment of psychological conditions [42
]. Therefore, future research should extend the use of semi-structured diagnostic interviews to other pediatric pain populations in order to get a more complete idea of how the diagnosis of PTSD may manifest in these youth.
When comparing youth with FAPDs with and without PTSD in the current sample, results revealed that youth with FAPDs and PTSD reported higher baseline rates of impairment in several areas of psychosocial functioning and one aspect of physical functioning. Specifically, higher rates of anxiety, pain catastrophizing, and somatization were observed in youth with PTSD versus no PTSD (p
’s < 0.05). These results were clinically significant (total score >30 vs. <30) in the case of pain catastrophizing. Depressive symptoms, pain intensity, and functional disability were not statistically or clinically significantly different between PTSD groups, although the functional disability was trending towards significance. These findings are generally consistent with previous research on the effects of psychological trauma and/or PTSD on pediatric or young adult chronic pain populations in that trauma/PTSD history has been most commonly found to affect psychosocial functioning vs. physical functioning [1
]. However, previous research on chronic pain and posttraumatic stress symptoms (PTSS) found a strong association between PTSS and facets of the pain experience, including intensity, interference, and unpleasantness [16
]. Given that functional disability was trending towards significance in the current sample, it may be that clearer differences in functional impairment between youth with and without PTSD can be found in larger or more diverse pain samples. Future research should continue to examine these relationships. The significant differences in somatic symptoms between youth with and without PTSD are also interesting in that somatization (i.e., somatic symptoms), like FAPD, often does not have a concrete medical explanation [3
]. In FAPDs in particular, it has been proposed that somatization mediates the relationship between abdominal pain and psychological dysfunction such as anxiety and/or depression [47
]. Concomitantly, research indicates that the presence of clinical anxiety symptoms negatively impacts outcomes in youth with FAPDs [7
]. It may be that the presence of PTSD via high somatization increases risk for poorer long-term outcomes in youth with FAPDs, but this has yet to be examined.
Results of exploratory analyses examining treatment response in youth with FAPDs and PTSD vs. no PTSD indicated youth with PTSD enrolled in the ADAPT intervention generally reported significantly higher rates of anxiety and somatization symptoms at post-assessment, although rates of these symptoms were also higher in those with PTSD at baseline. However, given that these differences persist post-treatment, these results are consistent with the larger trauma literature that has evidenced the negative impact that psychological trauma and/or PTSD history can have on psychosocial treatment response [24
]. As previous research in pediatric pain samples has also found that a significant subset of youth experience decreased response to traditional psychosocial treatment [18
], it may be that identifying potential risk factors for poorer outcomes such as psychological trauma and/or PTSD history will enhance positive treatment response and potentially increase prevention through the development or use of catered psychosocial interventions (e.g., Trauma-Focused Cognitive Behavioral Therapy [23
], Mindfulness-Based Stress Reduction [49
], etc.). Perhaps ADAPT could be further enhanced and refined to directly target PTSD that occurs in a large minority of youth with FAPDs. Future research should continue to examine potential avenues for prevention and intervention optimization in pediatric pain populations. Finally, a notable finding was the comparatively low rates of depressive symptoms vs. anxiety in the current sample, both at baseline and post-treatment. These findings are notable given the strong co-occurrence between anxiety and depressive symptoms in youth [50
] but consistent with other studies examining psychological impairment in youth with FAPDs [7
]. It may be that youth who are more likely to report anxiety over depression are at an increased risk for somatization and, in turn, abdominal pain. However, this remains unclear. It is also known that abdominal pain in childhood is a risk factor for the development of depressive symptoms over time [52
], so early identification and treatment of youth with FAPDs and comorbid anxiety are critical.
The current study has several strengths. To begin, the use of a clinician-administered semi-structured interview is currently the gold standard in the identification of posttraumatic stress disorder (PTSD) [29
] and likely minimized bias in reporting of trauma and PTSD [53
]. The recruitment and screening of treatment-seeking youth with FAPDs allowed for a nuanced understanding of how trauma impacts this chronic pain condition in youth in particular. The most significant limitations of the current study include the small sample size of youth with PTSD who received active treatment (n
= 4). This limits interpretability and ability to draw meaningful conclusions from results and likely underpowered analyses. The homogeneity of the participant sample, while consistent with published studies from other pediatric pain samples, also limits the generalizability of results to broader pediatric pain populations. Future research should replicate these analyses in larger samples and include more complex longitudinal examinations (e.g., controlling for baseline functioning) with larger treatment-seeking pain samples with and without PTSD.