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To determine if mothers of youth with functional abdominal pain (FAP) experience more anxiety, depressive, and somatic symptoms and disorders than mothers of unaffected children.
Four primary care pediatric practices in western Pennsylvania.
Mothers of 8- to 15-year-old children and adolescents presenting with FAP (59 cases) or for routine care in the absence of recurrent pain (76 controls).
Questionnaires and blinded interviews assessing anxiety, depressive, and somatic symptoms and disorders; quality of life; and service use.
On univariate analyses, mothers of FAP cases were significantly more likely than mothers of controls to have a lifetime history of irritable bowel syndrome (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.5-10.3), migraine (OR, 2.4; 95% CI, 1.1-5.3), and anxiety (OR, 4.8; 95% CI, 2.2-10.6), depressive (OR, 4.9; 95% CI, 2.2-11.0), and somatoform (OR, 16.1; 95% CI, 2.0-129.8) disorders than mothers of controls, and current anxiety, depressive, and somatic symptoms, poorer overall quality of life, and greater use of ambulatory health, but not mental health, services. Multivariate logistic regression found pediatric FAP to be most closely associated with maternal history of anxiety and depression (adjusted OR, 6.1; 95% CI, 1.8-20.8).
Functional abdominal pain may be better conceptualized as a disorder of emotion than a narrowly defined disorder of gastrointestinal function. Low rates of mental health service use by mothers of youth with FAP suggest that family health and illness attitudes deserve study.
Recurrent abdominal pain is a common pediatric problem, affecting 7% to 25% of youth1- 3 and accounting for 2% to 4% of pediatric office visits.4 Traditionally defined by at least 3 episodes of abdominal pain, occurring over at least 3 months, that are severe enough to affect child activities,2 it is associated with functional impairment and perceived health limitations.5- 7 Most affected children experience functional abdominal pain (FAP) (ie, recurrent abdominal pain for which a medical examination reveals no physical disease or biophysical process sufficient to explain the pain or its impact). Symptom-based criteria for functional gastrointestinal disorders, such as irritable bowel syndrome (IBS) (ie, FAP with at least 2 of the following: relief with defecation, change in bowel frequency, or change in bowel character), have been applied to adults8 and children.9 This study focused on broadly defined FAP because approximately 25% of youth with FAP will not meet the diagnostic criteria for a specific functional gastrointestinal disorder.10
Youth with FAP experience higher rates of anxiety, depressive, and other somatic symptoms and disorders than unaffected youth,3,5- 7,11- 14 consistent with findings for adults with IBS.15- 17 With few exceptions,18,19 family members of youth with FAP report an excess of FAP,2,3,20- 23 nongastrointestinal somatic symptoms (eg, headache),1,24 and anxiety and/or depressive symptoms3,6,13,22,24,25 compared with families of healthy controls and controls with gastrointestinal diseases. Unfortunately, studies of the parents of youth with FAP have relied exclusively on self-report questionnaires and have not included standardized interviews capable of generating categorical diagnoses of functional gastrointestinal disorders, such as IBS, or of psychiatric disorders (eg, anxiety, depressive, and somatoform disorders).
Aside from bias and possible artifact, explanations for the nonrandom association of FAP with anxiety and depressive disorders include unidirectional causal models (ie, one disorder causes the other) and shared diathesis models (ie, the disorders share a common underlying risk factor or factors or are different aspects of a singular causal process).26 Demonstrating a familial association between childhood FAP and the presence of FAP or anxiety, depressive, or other somatic disorders in the mothers of affected children could help determine whether pediatric FAP is best conceptualized as a gastrointestinal disorder, an emotional disorder, or some hybrid. Accordingly, we compared mothers of youth with FAP with mothers of pain-free controls using measures of anxiety, depressive, and somatic symptoms and disorders, and health service use and overall quality of life. We hypothesized that the mothers of FAP cases would be significantly more likely than those of controls to do the following: (1) meet the diagnostic criteria for IBS, anxiety, depressive, and somatoform disorders, and migraine; (2) report higher levels of anxiety, depressive, and somatic symptoms; (3) report lower levels of health-related quality of life; and (4) report higher levels of health and mental health service use.
The Human Rights Committee of the Children's Hospital of Pittsburgh approved the study. Seventy youth presenting with FAP and 81 pain-free controls, aged 8 to 15 years, inclusive, were consecutively recruited by office-based screening from 4 primary care pediatric practices in western Pennsylvania. To minimize the potential for referral bias, cases were identified only by screening rather than by direct physician referral. Exclusion criteria included explanatory physical disease, “atypical” symptoms suggestive of causal disease (eg, fever or blood in the stool), serious nongastrointestinal disease (eg, diabetes mellitus), mental retardation, and pregnancy. Controls were recruited from the pool of screened youth without FAP, headache, chest pain, or limb pain in the previous 3 months. When a child with FAP was identified, 3 potential same-sex controls presenting for routine care were identified from sequentially collected screens in the same practice. Participants were 84.4% white and 60.0% female, with a mean age of 11.8 years, and did not differ from those who declined participation or could not be contacted, except that decliners were more likely to be white. Cases did not differ from controls with regard to sex or race/ethnicity, but were younger (mean [SD] age, 11.3 [2.2] vs 12.1 [2.2] years; t = 2.25; P=.03). Data provided by mothers were analyzed given the relatively few participating fathers. A sample of 59 case and 76 control mothers completed self-report questionnaires and a standardized family history assessment delivered by an interviewer blind to subject status. Participants were compensated. Study instruments included the following:
Brief Symptom Inventory: a 53-item psychometrically sound measure of psychiatric distress in adults, including somatization, anxiety, and depression.27
Beck Depression Inventory and Beck Anxiety Inventory: widely used and brief self-report measures of depressive and anxiety symptoms that successfully discriminate depression and anxiety.28,29
Adult Somatization Inventory: a 35-item scale that assesses a broad range of somatic symptoms in adults.22
Family Informant Schedule and Criteria (revised for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition): a semistructured interview designed to assess family history of psychiatric disorder in first-degree relatives.30 The interview was modified to assess for somatoform disorder, IBS, migraine, fibromyalgia, and chronic fatigue syndrome, as used in previous research.31
Rome II Checklist for Functional Gastrointestinal Disorders: a self-report measure developed for the assessment and diagnosis of functional gastrointestinal disorders, such as IBS, in adults.8
Medical Outcomes Study 36-Item Short-Form Health Survey32- 34: a psychometrically sound assessment of functional health and well-being, yielding scores in 8 domains: (a) physical functioning (health limitations in physical activities), (b) physical role (physical health limitations in usual role activities), (c) bodily pain, (d) general health perceptions, (e) vitality (energy), (f) social functioning (limitations in social activities because of physical or emotional problems), (g) emotional role (emotional health limitations in usual role activities), and (h) mental health (psychological distress and well-being).
National Health Interview Survey35: an assessment of outpatient ambulatory and specialty health service use, emergency visits, and hospitalizations.
All statistical analyses were performed using a commercially available software program (SPSS, version 14; SPSS Inc, Chicago, Ill). Categorical data were compared between the groups using either the χ2 statistic or, when any 1 cell had an expected value of less than 5 or when there was a 0 cell, the Fisher exact test. Continuous data were examined using the 2-sample t test with equal or unequal variances, as appropriate. Data are presented as rates or means and standard deviations with differences in mean ratings between the groups. We also present odds ratios and 95% confidence intervals. We constructed a multivariate logistic regression model to examine the relationship between pediatric FAP and maternal physical (IBS and migraine) and psychiatric (anxiety and depressive) disorders, controlling for the potential confounding effects of demographic characteristics that differed between the groups. Two demographic variables, age and family intactness, were included in this model because they survived a backward stepwise logistic regression analysis of potential demographic covariates (P<.05). The goodness of fit of the full model was assessed by the Hosmer-Lemeshow statistic. Before conducting the logistic regression analyses, we performed a set of correlation analyses of all potential predictors to assess for multicollinearity. Because of the strong correlation between maternal anxiety and depressive disorders (ρ = 0.57), we created a composite variable composed of 4 mutually exclusive categories: “no anxiety or depressive disorder,” “anxiety disorder alone,” “depressive disorder alone,” and “both anxiety and depressive disorder.”
Compared with the mothers of controls, FAP case mothers were younger, less likely to be married, and less likely to be living with the child's biological father. The maternal demographic characteristics are further detailed in Table 1.
Mothers of FAP cases were significantly more likely than mothers of controls to meet lifetime diagnostic criteria for IBS using the Family Informant Schedule and Criteria interview. Mothers also completed a self-report checklist that confirmed differences in the rates of IBS between FAP case mothers and mothers of controls (29.3% vs 6.7%; P=.001; odds ratio, 5.8; 95% confidence interval, 2.0-16.9). Mothers of youth with FAP were significantly more likely to have lifetime histories of migraine, chronic fatigue syndrome, and somatoform disorders than mothers of controls (Table 2).
Anxiety and depressive disorders were significantly more likely in FAP case mothers than in mothers of controls, with more than half indicating a lifetime anxiety or depressive disorder (Table 2) and 41.1% meeting lifetime criteria for anxiety and depressive disorder (Figure). Generalized anxiety disorder was the most common anxiety diagnosis in FAP case mothers. The degree of diagnostic overlap is striking, with 15 (93.8%) of the 16 FAP case mothers with IBS reporting a lifetime history of anxiety or depression and 13 (81.2%) reporting anxiety and depression.
Overlapping diagnoses for the 56 mothers of youth with functional abdominal pain: irritable bowel syndrome (IBS), anxiety, and depression.
Large differences in mean ratings were noted between mothers of children with FAP and mothers of controls on all self-report measures of psychiatric and somatic symptoms (Table 3).
The FAP case mothers had poorer health-related quality of life in all domains than mothers of controls (Table 4).
Mothers of youth with FAP were significantly more likely to have made 10 or more ambulatory health visits during the previous 6 months than mothers of controls, and there was a trend suggesting more emergency department visits (Table 5). The groups did not differ with regard to mental health visits despite greater psychiatric symptoms and disorders in FAP case mothers.
Table 6 shows the results of the multivariate regression analyses. Maternal factors associated with pediatric FAP included younger age and lifetime history of anxiety and depression. Despite the apparently large differences between the FAP case mothers and control mothers on univariate analyses for IBS and migraine, maternal IBS and migraine were not associated with pediatric FAP after adjusting for demographic correlates and maternal anxiety and depression. The Hosmer-Lemeshow goodness-of-fit test36 indicated adequate fit for the model.
Mothers of youth with FAP are significantly more likely to have anxiety and depressive disorders than mothers of unaffected youth, and have somatic disorders at rates greater than what might be expected in the population at large given population prevalences of 3% to 20% for IBS,37 10% to 12% for migraine (15%-25% for women),38 and 0.007% to 2.8% for chronic fatigue syndrome.39 On univariate analysis, mothers of youth with FAP were more likely to have IBS, somatoform disorders, and migraine than were controls, but pediatric FAP proved to be most closely associated with a maternal history of anxiety and depression in the final multivariate model. A lifetime history of anxiety and depression was reported by 41.1% of mothers of youth with FAP, with the most common specific diagnoses being major depressive disorder (46.4%) and generalized anxiety disorder (39.3%). These rates of maternal emotional disorder are considerably higher than the reported adult population prevalences of 20.8% for any mood disorder (major depressive disorder, 16.6%) and 28.8% for any anxiety disorder (generalized anxiety disorder, 5.7%),40 yet are not especially surprising given studies5,6,11 demonstrating high rates of anxiety and depressive disorders in youth with FAP. In addition, our findings are consistent with results from a previous study31 comparing first-degree relatives of adults with a childhood history of FAP with those of controls with a history of nongastrointestinal childhood illness.
Study results challenge the narrow and somewhat popular conceptualization of FAP as a primary disorder of gastrointestinal function for which associated emotional distress is viewed as the consequence of inadequate coping and/or physical distress per se. Our findings support a broader view of FAP that regards emotional factors as being intrinsic to the disorder. Additional support for conceptualizing FAP as a gastrointestinal and emotional disorder is provided by findings that childhood FAP predicts emotional disorders later in life,31 that anxiety tends to precede FAP onset in most affected youth,5 and that physiologic responses of youth with FAP to social stressors are more akin to those of anxiety-disordered youth than healthy controls.41 Several studies42- 45 of adults with FAP also suggest familial transmission of a broad vulnerability to anxiety, depression, and somatic symptoms of distress rather than to FAP alone. Although not conclusively studied, treatments usually applied to anxiety and depressive disorders, such as cognitive behavioral psychotherapy46- 48 and selective serotonin reuptake inhibitors,6 have also shown promise in the treatment of youth with FAP, again providing at least circumstantial evidence for more than a peripheral association.
Anxiety and depressive disorders are commonly comorbid across the lifespan, and especially high rates of comorbidity for generalized anxiety disorder and major depressive disorder49,50 have been explained by a common diathesis51 and genetic pleiotropy (ie, different phenotypic consequences of a common genetic predisposition). Whether FAP may be a manifestation of such a common diathesis is worthy of study, and it is of interest that FAP in adults has been associated with the same functional polymorphism in the promoter region of the serotonin transporter gene52 that is associated with vulnerability to anxious temperament and depression.53 Available twin studies54,55 support the role of heredity and nongenetic factors in the development of IBS, but have not included detailed psychiatric assessments. Disentangling the nature of the relationship between FAP, anxiety, and depression will likely require longitudinal, family, and biological studies, including studies of differential response to treatments.
Finally, despite their greater psychiatric illness burden, mothers of youth with FAP were no more likely to use mental health services than the mothers of controls. This finding suggests that families of youth with FAP may be disinclined to seek potentially helpful mental health services, perhaps because of individual difficulties in recognizing emotional distress, differences in health beliefs, and/or a heightened sensitivity to stigma. Clinicians should be alert to possible emotional disorder in the mothers of youth with FAP.
Correspondence: John V. Campo, MD, Division of Child and Adolescent Psychiatry, Pediatric Behavioral Health Services, Columbus Children's Hospital, The Ohio State University, 700 Children's Dr, Timken H-205, Columbus, OH 43205 (firstname.lastname@example.org).
Accepted for Publication: August 12, 2006.
Author Contributions: Dr Campo had full access to study data and takes full responsibility for data integrity and the accuracy of analyses. Study concept and design: Campo, Bridge, Walker, Di Lorenzo, and Brent. Acquisition of data: Campo, Lucas, and Brent. Analysis and interpretation of data: Campo, Bridge, Savorelli, Walker, Di Lorenzo, Iyengar, and Brent. Drafting of the manuscript: Campo, Bridge, Savorelli, Di Lorenzo, and Brent. Critical revision of the manuscript for important intellectual content: Campo, Bridge, Lucas, Walker, Di Lorenzo, and Brent. Statistical analysis: Bridge, Savorelli, and Iyengar. Obtained funding: Campo. Administrative, technical, and material support: Campo and Lucas. Study supervision: Campo, Di Lorenzo, and Brent.
Financial Disclosure: Dr Campo has received past grant support from Forest Laboratories, Inc, and has served as a consultant to Eli Lilly and Company.
Funding/Support: This study was supported by grants K23 MH01780 (Dr Campo) and MH66371 (Dr Brent) from the National Institute of Mental Health.
Role of the Sponsor: The funding bodies had no role in data extraction and analyses, in the writing of the manuscript, or in the decision to submit the manuscript for publication.
Acknowledgment: We thank Cari Dombrowski, Sarah Altman, and Michelle Saunders for data collection; Ian Miller and Mary Ehmann for data management; R. Bruce Lydiard, MD, Ron Dahl, MD, David Kupfer, MD, and James Perel, PhD, for advice and encouragement; and Harold Altman, MD, David Wolfson, MD, and the physicians, staff, and administration of Children's Community Pediatrics for ongoing support and cooperation.
Campo JV, Bridge J, Lucas A, Savorelli S, Walker L, Di Lorenzo C, Iyengar S, Brent DA. Physical and Emotional Health of Mothers of Youth With Functional Abdominal Pain. Arch Pediatr Adolesc Med. 2007;161(2):131-137. doi:10.1001/archpedi.161.2.131