Change the Name: “Functional” is Lousy

A recent commentary explains why “functional” pain is such a lousy term (JAMA Pediatr. Published online June 02, 2014. doi:10.1001/jamapediatrics.2014.530 –thanks to Ben Gold for this reference).  In pediatric GI practice, functional gastrointestinal disorders (FGIDs) constitute a large part of clinical work.

The author, Neil Schechter from the Chronic Pain Program in Boston, makes several important observations:

  • “There is general dissatisfaction with the terminology.”  This stems from the fact that “in common parlance today, functional disorders are typically assumed to be a product of psychological distress.” Yet, parents/patients are “not ready to accept a strictly psychological explanation.”
  • The idea that functional pain is solely a psychological disturbance is inaccurate.  Though, anxiety and depression are common associated problems which often contribute to symptoms.  He states that “hyperexcitability” of the nervous system is “the core biological link and final common pathway for the creation of functional pain disorders.”
  • This category should be labeled dysfunctional pain.  “In effect, calling pain ‘functional’ is like calling disease, ‘ease.'”
  • These disorders frequently respond to centrally acting therapies including antidepressants, anticonvulsants, exercise, cognitive behavioral therapy, and acupuncture.
  • “The search for an appropriate term for these pain problems is far more than semantic…[a patient’s] understanding of their illness is clearly linked to their compliance with medical advice…it may stem their desire for additional costly investigation.”
  • Dr. Schechter proposes the term “primary pain disorder.”  “Unlike Shakespeare’s rose, functional pain would benefit from a new name.”

Take-home message: I wish I had written this commentary.  Explaining “functional” pain and “irritable bowel syndrome” are Sisyphean tasks.  Better nomenclature could ease the burden.  Join me in abandoning the use of the word “functional.”

In the same issue, an editorial on the “Role of Celiac Disease Screening for Children with Functional Gastrointestinal Disorders” (JAMA Pediatr. 2014;168(6):514-515. doi:10.1001/jamapediatrics.2013.5418) comments on a study (JAMA Pediatr. 2014; 168(6):555-60) in the same issue which reports a 4-fold higher prevalence of celiac disease among children who meet clinical criteria for irritable bowel syndrome.  The study reports the results from a cohort of 992 children identified with recurrent abdominal pain in a primary care setting.  In the editorial, the authors note:  “When grouped together, the prevalence rate of celiac disease among all children with FGIDs (IBS included) approaches 2%.  Celiac disease screening in this population would result in a positive tTG-IgA test result in 4%…However, 53% of all positive test results would be falsely elevated.”  As such the editorial advocates in favor of screening for celiac disease in children with IBS but not all FGIDs.

Related blog posts:

“If all you have is a hammer…”

In my training, one of my mentors would be critical of the mentality “scope first, think second.”  He was concerned that too many gastroenterologists/pediatric gastroenterologists used endoscopy as a tool simply “because if all you have is a hammer, the world looks like a nail.”

A recent publication (Clin Gastroenterol Hepatol 2014; 12: 963-69) on first glance, however, provides ammunition to the “scope first” gastroenterologists and undermines the concept that “functional” GI disorders vastly outnumber “organic” GI disorders.  The key finding was that esophagogastroduodenoscopy (EGD) provided an “accurate” diagnosis in 38%.  This included reflux esophagitis in 21%, eosinophilic esophagitis (EoE) in 5%, eosinophilic gastroenteritis (EGE) in 4%, H pylori in 2%, celiac disease 0.6%, and Crohn’s disease 0.4%. This finding is dramatically higher than previous studies.  In fact, in a recent published study (Understanding Idiopathic Nausea | gutsandgrowth) on idiopathic nausea, a control group of patients with chronic abdominal pain had a normal endoscopy in 100%!

In this prospective study of 290 children (ages 4-18 years with a mean age of 11.9 years), the primary indication for upper endoscopy was chronic abdominal pain.  Of this 290, 216 had at least 1 alarm feature and 125 had at least 2 alarm features.  Alarm features were considered to be the following:

  • Nighttime awakening 33.3%
  • Weight loss 15.6%
  • Family history of IBD 8.4%
  • Vomiting 7.8%
  • Dysphagia 6.9%
  • Nocturnal diarrhea 6.7%
  • Gastrointestinal bleed 5.8%
  • Chronic diarrhea 5.8%
  • Unexplained fever 4.4%
  • Arthralgia 4.0%
  • Growth failure 2.4%
  • Perirectal disease 0.7%
  • Delayed puberty 0.2%

There is little debate that abdominal pain in combination with true alarm symptoms (True red flags in recurrent abdominal pain | gutsandgrowth) merits further evaluation.  The aspect of this report that is worthy of close inspection is the diagnostic yield in the 74 patients without alarm symptoms.  The authors note that 25 (33.7%) had a diagnosis established with EGD including 16 with reflux esophagitis, 4 with EGE, 2 with EoE, 1 with erosive esophagitis, 1 with celiac and 1 with H pylori.  The diagnostic criteria for EGE included ≥10 eosinophils per hpf in the stomach and ≥20 eosinophils per hpf in the duodenum.

The authors note that the diagnostic yield was based on gross endoscopic findings in procedure notes or histologic changes in biopsy reports; “final pathology report on biopsies provided the data source for histologic diagnosis.”

In my opinion there are multiple flaws of this prospective study.

1. There is a very high rate of reflux esophagitis in both the alarm group and the non-alarm group patients with chronic abdominal pain.  Of the entire cohort (n=290), the authors identified reflux esophagitis in 21% and this was “primarily histologic esophagitis.”  Furthermore, the authors state that “the presence or response to PPI therapy was not predictive of esophagitis or GERD.”  So, the obvious problems:

  • Presence of histologic reflux esophagitis varies widely based on the interpreting pathologist.  In a prospective study, more than one pathologist interpreting the histology would be useful.
  • Presence of histologic reflux esophagitis does not exclude the likelihood of coexisting functional disorders (related blog post: Why didn’t patient with documented reflux get better with PPI …).  As a practical matter, “slight” or “focal” esophagitis on histology has questionable real-world relevance in pediatric gastroenterology.
  • The authors acknowledge, “current expert consensus indicates that histology has limited value in evaluating pediatric GERD.”  Yet this diagnostic finding is one of the reasons why the authors claim that EGD is so valuable.

2. In the entire cohort, the authors try to validate their findings by indicating that identification of a diagnosis led to medical therapy that was “effective in approximately 67%” of children with short-term followup. (Only 81% had short-term followup outcomes available).  Yet, there is no control group.  How many children with chronic abdominal pain will improve for a short period without an EGD-based diagnosis?  The answer: a lot of them.

3. Limitations include selection bias toward those with more severe symptoms or alarm symptoms.  In addition, this study included only a small number who were considered to have no alarm symptoms.  Finally, the short-term followup makes conclusions about the response to therapy questionable.

This study will be a useful reference for any pediatric gastroenterologist who wants to justify the need for an endoscopy.  The authors note “the majority of children in our study (93%) met criteria for functional gastrointestinal disorders, and a significant proportion (38%) still had significant histologic findings.  Therefore, we conclude the Rome III criteria alone are not sufficient to identify children who require upper endoscopy, and screening for alarm symptoms has limited utility.”

In my opinion, the reliance on histology as well as selection bias weaken the findings of this study.  If a patient with a histologic diagnosis of reflux (or several other entities) and a presentation of chronic abdominal pain does not improve, the pediatric gastroenterologist should remember that only “a poor carpenter blames his tools.”

Bottomline: EGD remains an important tool in evaluating abdominal pain.  However, I think this study substantially overestimates its utility.

Related blog posts:

 

 

 

 

What NOT to say with functional pain

A recent article crossed my desk (from the “G-force”) which I hadn’t seen (or at least remembered).  So, although it is not new, it is a useful reference (Pain 2006; 122: 43-52).

In brief, the authors divided 223 children (n-104 with recurrent pain, n=119 healthy children) between ages 8-16 into 3 groups: attention, distraction, and no instruction.  After the children consumed water until they felt “completely full,” they were observed with their parents.  Parents in the attention and distraction groups had received video and written instructions; whereas the no instruction parents watched a video about the university.

Questions/statements that were typical in the attention group:

  • “I know it hurts now, but you’ll be OK later”
  • “What doe it feel like?”
  • “I can imagine it must feel really uncomfortable”

Questions/statements that were typical in the distraction group:

  • “Let’s talk about something else to get your mind off of it.  Tell me about ____”
  • “What would you like to do this evening?”

Key findings:

  1. Complaints nearly doubled under conditions of parent attention and were reduced by half under conditions of distraction (in comparison to the no instruction group).
  2. Female patients in this study had greater increase in pain complaints in the attention group than male patients.
  3. After water loading, children with a history of pain had significantly more complaints in the attention group than healthy children.
  4. “Unlike parents of well children, no parent of a pain patient rated attention as having any potential for negative impact on their child.”

Take home message (from Oscar Wilde -quoted in article): “While sympathy with joy intensifies the sum of joy in the world, sympathy with pain does not really diminish the amount of pain.”

Related blog post:

Anxiety and Functional Abdominal Pain | gutsandgrowth

High Rates of Anxiety Develop in Kids with RAP

From NY Times review of a recent Pediatrics study:

Children with chronic stomach pains are at high risk for anxiety disorders in adolescence and young adulthood, a new study has found (goo.gl/I2UvHP ), suggesting that parents may wish to have their children evaluated at some point for anxiety.

Researchers at Vanderbilt University tracked 332 children with recurring stomachaches that could not be traced to a physical cause — so-called functional abdominal pain — comparing them as they reached young adulthood with 147 children who had never had such stomachaches.

About half the teenagers and young adults who had had functional abdominal pain as children developed an anxiety disorder at some point, compared with 20 percent of the control group, the researchers found. The vulnerability to anxiety persisted into adulthood even if the pain had disappeared, although the risk was highest if the pain continued.

Forty percent of the children with functional abdominal pain went on to experience depression, compared with 16 percent of those who had never had these stomachaches.

The study was published on Monday in the journal Pediatrics.

“What this study shows is a strong connection between functional abdominal pain and anxiety persists into adulthood, and it drives home the point that this isn’t by chance,” said Dr. John V. Campo, chairman of the department of psychiatry at Ohio State University, who was not involved in the new study….

Chronic abdominal pain affects 8 percent to 25 percent of school-age children. The problem can lead to school absences and take a toll on families.

“Somebody might say, ‘Of course they have mental issues or they are emotionally distressed — it’s because of the pain,’ ” said Lynn S. Walker, senior author of the study and director of the division of adolescent health at Monroe Carell Jr. Children’s Hospital at Vanderbilt.

“But we found even if the pain went away, these adolescents and young adults still have anxiety,” Dr. Walker said. “So maybe we need to treat their anxiety.”

The state-of-the-art treatment for functional abdominal pain is rehabilitative, focused on getting patients to participate in daily activities despite their stomachaches. “There’s no question that there are triggers for the pain, but the problem is in the perception of the pain and adaptation to the pain,” said Dr. Samuel Nurko, director of a functional abdominal pain center at Children’s Hospital Boston.

Dr. Nurko compared the pain to a light on a dimmer switch, which psychological techniques can help children control. “You don’t take away the pain,” he said. “You ‘dim’ it to be able to cope better.”

The new study underscores the importance of screening children with the condition for anxiety or depression, the authors said. Anxious children tend to be good children who are concerned about doing their best, Dr. Walker said, and parents may be flummoxed by the suggestion that such a child could be grappling with a mental health issue.

Related blog link:

Anxiety and Functional Abdominal Pain | gutsandgrowth  This link has additional links on related material.

True red flags in recurrent abdominal pain

For pediatricians and pediatric gastroenterologists alike, identifying which children need additional workup for recurrent abdominal pain (RAP) is facilitated by recognizing “red flags.”  “Red flags” are clinical features that indicate a higher likelihood of a nonfunctional disorder.  A recent study notes that reports of waking from sleep and joint pains do not distinguish functional from nonfunctional causes of RAP (J Pediatr 2013; 162: 783-7).

This study, performed between 2005 to 2008, had patients presenting to an outpatient pediatric gastroenterology clinic for RAP prospectively complete a detailed questionnaire. Data, though, was extracted retrospectively. In this population (n=606), 85% were Caucasian.  After their evaluation, patients with functional GI diseases (FGID, n=478) were compared with patients confirmed with Crohn’s disease (CD, n=128).  All FGIDs underwent biochemical testing, 41% had upper endoscopy, and 32% underwent colonoscopy.

Additional key findings:

  • Using a tree analysis, the cumulative sensitivity for Crohn’s disease was 54% with the presence of anemia, 78% when blood in stool was added to anemia, and 94% when weight loss was added as well.
  • FGID patients were more likely to report stress and headaches, more likely to have family history of FGID, and less likely to have anemia, hematochezia, or growth issues.
  • FGID patients were more likely to experience vomiting.

The sensitivity and specificity of these symptoms/signs will vary based on the population.  For a general pediatric clinic, it is likely that the sensitivity of these red flags would remain high; the specificity would likely be lower than in a pediatric gastroenterology office due to the increased prevalence of functional diseases in the general pediatric setting.

Related blog posts:

Born this way

“Baby I was born this way” is applicable to more than just Lady Gaga.  It looks like this mantra extends to functional somatic symptoms (FSS) (J Pediatr 2013; 162: 335-42).

This study which was part of a longitudinal birth cohort study, Copenhagen Child Cohort CCC2000, included 6090 children born in a well-defined geographical area around Copenhagen, Denmark in 2000.  At 5-7 year follow-up, a random sample of 3000 members of the cohort were selected; only 2912 were included as 79 were unreachable and 9 had died.  Subsequently, 1327 had complete data and were the final study sample.

FSS were measured by the Soma Assessment Interview.  In the first 10 months of living, regulatory problems which included at least 2 of 3 problems of feeding, sleeping, or tactile reactivity predicted impaired FSS at 5-7 years with aOR 2.9.  Maternal psychiatric illness during the child’s first year of life conveyed an aOR of 7.1.

FSS (ie, headache and recurrent abdominal pain) could develop due to a number of possible mechanisms:

  • hypersensitivity to stimuli
  • autonomic hyper-reactivity
  • regulatory problems may be risk factors for mood and anxiety disorders

While the strengths of this study included prospective data collection by health professionals and a fairly large sample size, there were still numerous limitations.  Measuring regulatory problems in infancy is not fully validated.  In addition, the designation of FSS is problematic as it is difficult to fully exclude organic etiologies which could present with similar complaints.

The association of maternal psychopathology with the development of FSS in their children is of interest.  It is not clear if this risk is due to nurturing effects (i.e., child’s capacity to self-regulate) or due to nature (i.e., inherited susceptibility).

Pain changes brain

For several years, there has been research showing changes in PET scans and functional MRI in association with functional abdominal pain.  A recent article goes a step further showing microstructure  brain changes in patients with chronic pancreatitis (Gut 2011; 60: 1554-62).

This study examined 23 patients with pain due to chronic pancreatitis and 14 controls.  Using a 3T MR scanner, apparent diffusion coefficients (ADC) and ‘fractional anistotropy’ (FA) values were assessed in numerous parts throughout the brain.  This new technology, uses an MRI for diffusion tensor imaging which assesses changes in white and grey matter microstructure not evident with more conventional imaging.  Chronic pancreatitis patients had increased ADC in the amygdala, cingulate cortex, and prefrontal cortex.  In addition, FA values were reduced in the cingulate cortex and secondary sensory cortex.  These areas of the brain with these changes are known to be involved in the processing of visceral pain.  Microstructural changes were correlated to patients’ clinical pain scores.  Some of the changes can be influenced by other factors including alcohol usage, depression, Alzheimer’s or diabetes.

This study echoes findings from others that demonstrate structural reorganization of the brain in association with chronic pain.

Additional references:

  • -Gastroenterology 2010; 139: 1310. n=15 IBS women, 12 controls.  IBS pts have emotional modulation of neural responses to visceral stimuli (eg rectal stimulation) –based on functional MRI studies.
  • -Gastroenterology 2006; 130: 26 & 34. Functional MRI measured in response to barostat show increased sensitivity in pts c IBS. Also, altered 5-HT signaling in IBS-D & IBS-C.
  • -J Pediatr 2001; 139: 838-843. Pts c IBS, RAP more sensitive to visceral perception in rectum and stomach respectively.
  • -Gastroenterology 2005; 128: 1819. Brain response to visceral aversive conditioning –>similar cortical responses between actual and anticipated stimuli.
  • -Cereb Cortex 2010; 20: 1409-19.  Changes in brain anatomy associated with neuropathic pain following spinal cord injury.
  • -J Am Acad Child Adolesc Psychiatry 2010; 49: 173-83.  White matter microstructure changes in adolescents with major depression.

Unexplained chest pain

Not surprisingly -unexplained pediatric chest pain has a high association with anxiety/psychiatric disorders (J Pediatr 2012; 160: 320).  In this study, the authors compared patients (8-17 years) with chest pain (n=100) to a cohort referred with innocent heart murmur (n=80).  In addition to cardiology evaluation, patients had a structured interview and a child health questionnaire to assess for psychiatric disorders; also, the investigators interviewed the parent(s).

Based on DSM-IV criteria, 70% of chest pain patients had an anxiety disorder and 9% had depression.  In contrast, 33% of heart murmur patients had an anxiety disorder and none were depressed.  Among the chest pain subjects, 26% had abdominal pain and 26% had headaches -both higher than the control group, 9% and 10% respectively.  Also, 90% of patients with chest pain had psychiatric disorders which preceded the chest pain.

For pediatric gastroenterologists, a take home message from this article is that chest pain is quite similar to abdominal pain (see references below); it might be interesting to discuss with cardiologists.

  • Do cardiologists experience the same reluctance from families to seek help from mental health?
  • How much testing is required before a functional diagnosis is accepted?
  • Do they follow patients with functional chest pain or send back promptly to primary care physician?

This article does not examine parental mental health issues.  This would be interesting.  In functional abdominal pain, maternal anxiety has been ascribed as the most consistent predictor of outcome (Acta Paediatr 2007; 96: 697-701).  Another factor that would be of interest would be level of activity; exercise helps reduce symptoms of irritable bowel/abdominal pain.

At the same time, the issue of reflux is not addressed by this article and not infrequently the issue of whether reflux is causing chest pain needs to be considered.  An article (Gut 2011; 60: 1473-78) regarding chest pain in adults indicates that patients with pH-probe (or endoscopic) proven GERD often respond partially (>50% reduction in symptoms) to PPI use.  This study reviewed RCTs involving chest pain and PPIs -six met inclusion criteria.  The RR of therapeutic gain for PPI usage was 4.3 for those with proven reflux and 0.4 for those with pH-probe (or endoscopic) negative chest pain.  Interestingly, in this study, heartburn was not predictive of whether chest pain was due to GERD on pH study.

Additional references:

  • -Pediatr Emerg Care 2010; 26: 830-6.  Psychopathology among children presenting to ER with unexplained chest pain.
  • -Clin Gastro 2008; 6: 329-32.  Depressive symptoms common in RAP -45%
  • -Pediatrics 2004; 113: 817.  Anxiety & depression commonly associated with RAP.  anxiety in ~79%, depression ~43%; anxiety often precedes RAP.
  • -JPGN 2011; 53: 200. n=98. 79% of FAP responded to low dose tricyclics
  • -Gastroenterology 2009; 137: 1261, 1207– Editorial.  Amitriptyline helped in 66% vs 58% with placebo. n=90. dose 10mg <35kg, 20mg >35kg. 89% had failed Rx prior to study. ‘Inability to use placebo.. in practice may justify amitriptyline’ Rx. Consider hypnotherapy/CBT first.
  • -Gut 2011; 60: 1473-78. PPI use in unexplained chest pain.
  • -Pain 2006; 122: 43-52. (Walker LS et al), J Pain 2006; 7: 319-26.  Distraction/ignoring important.
  • -J Pediatr 2009; 154: 313 (editorial), 322. Prospective school study. n=237. Weekly prevalence of abd pain was 38%. 18% with persistence for >12 weeks.
  • -Clin Gastro Hepatol 2008; 6: 329-32.  FAP persists into adulthood in 1/3 to 1/2 of cases.
  • -Gastroenterol 2006; 130: 1459-1465.  Functional esophageal d/o.
  • -Clin Gastro & Hep 2006; 4: 558. Review.
  • -Ann Heart J 2000; 40: 367-372.  Sertraline decreased chest pain independent of mood alteration/psychological scores.