Current Mortality from Being Born Premature

A recent study (Patel RM et al. NEJM 2015; 372: 331-40) provides prospectively collected data on 6075 deaths among 22,248 live births with gestational ages 22-29 weeks from the U.S NICHD Neonatal Research Network. between 2000 thru 2011:

Key findings:

  • Improved death rate in most recent period of study:  number of deaths per 1000 live births was 275  (2000-2003), 285 (2004-2007), 258 (2008-2011)
  • While there were fewer pulmonary deaths with time, the deaths attributed to necrotizing enterocolitis increased: number of deaths per 1000 live births was 23 (2000-2003), 29 (2004-2007), 30 (2008-2011).  Necrotizing enterocolitis was the leading cause of death between 15-60 days of life (Figure 1).
  • Overall, 40.4% of deaths occurred within 12 hours after birth.  Only 17.3% occurred after 28 days of life.
  • For the entire study period, the rate of death (per thousand) was associated with gestational age: 949 (22 weeks), 730 (23 weeks), 427 (24 weeks), 258 (25 weeks), 157 (26 weeks), 115 (27 weeks), 78 (28 weeks)
  • The authors speculate that the overall reduction in death rate is likely related to more aggressive respiratory care (for bronchopulmonary dysplasia); one marker of this was increased usage of high-frequency ventilation.

Bottomline: While there has been improvement, being born premature is associated with high mortality.

Is it Safe to Chew Gum Before Anesthesia?

According to a recent study highlighted in Gastroenterology & Endoscopy News, gum chewing immediately prior to anesthesia is probably safe.

Here’s an excerpt:

Patients who are fasting before upper endoscopy can safely chew gum up until the time of the procedure, researchers have found…

The prospective randomized controlled study evaluated the effect of gum chewing on volume and pH of gastric contents in 67 patients scheduled to receive IV conscious sedation for upper endoscopy. The night before the procedure, patients were randomly assigned to chew gum until the start of sedation…—or to not chew gum, with no limit on the number of pieces or how long they could chew.

The median volume suctioned from the gum chewers was 13 mL, compared with 6 mL for non-gum chewers. Similarly, gastric fluid also was greater for gum chewers—0.35 versus 0.11 mL/kg for patients who did not chew gum. “The 0.35 mL/kg is still under 0.4 mL/kg, which is where the risk for aspiration comes into effect,” he noted…The pH also did not change.

Take-home message: While this study provides some reassurance, I suspect that asking families to give nothing before an endoscopy will be easier than trying to explain the nuances and risks for aspiration.  For those who have only had gum, though, it may not be necessary to cancel their case.

From Atul Gawande's Twitter Feed

From Atul Gawande’s Twitter Feed

 

 

 

Gut Microbiome, Crohn’s Disease and Effect of Diet

At this past year’s NASPGHAN conference, Bob Baldassano indicated that a low-residue diet probably does not makes sense for the majority of patients with Crohn’s disease because it would not promote a ‘healthy’ gut microbiome.  Another article (Walter SS, Quiros A, et al. SOJ Microbiol Infect Dis 2014; 2: 1-13) supporting this argument has been published. (Thanks to Ben Gold for giving me this reference.)

In this study, the authors examined the gut microbiome from two healthy volunteers and compared them to six patients with Crohn’s disease (CD) (ages 16-50).  The CD cohort were in clinical remission and were not receiving probiotics.  Subjects were randomized to either a low-residue diet (LRD) or a specific carbohydrate diet (SCD).

Besides having some cool figures to explain their results, the key points:

  • The complexity of the gut microbiome was lower in IBD patients compared to healthy controls
  • Bacteroides fragilis was increased in fecal samples of IBD positive patients
  • There was a temporal response of gut microbiome to SCD with increased microbial diversity while the LRD diet was associated with a reduced diversity of the microbiome in patients with CD

While the number of patients participating in this study are low, the affects of these diets can still be measured due to the trillions of microbes in the gut microbiome.

Also noted: Church PC, Turner D, et al. Aliment Phamacol There 2015; 41: 153-66. “Systematic review with meta-analysis: magnetic resonance enterography for the detection of inflammation and intestinal damage in Crohn’s disease.”

How the gut micro biome may affect other diseases including Multiple Sclerosis: Study Hints Gut Microbiome Plays a Role in Multiple Sclerosis (Link to Gastroenterology & Endoscopy News)

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From NASPGHAN:  Introducing New Website for Teens with Inflammatory Bowel Diseases: JustLikeMeIBD.org  PRESS RELEASE

New York, NY- January 20, 2015 – The number of inflammatory bowel disease (IBD) patients in the U.S. has now increased to an estimated 1.6 million, with approximately 5 percent of that patient population under the age of 18. In response to the growing number of kids with IBD, the Crohn’s & Colitis Foundation of America (CCFA) along with the NASPGHAN Foundation for Children’s Digestive Health and Nutrition, has launched a new website called “Just Like Me” for teenagers with Crohn’s disease and ulcerative colitis.

The interactive site will feature stories and videos from teens with IBD as well as information on school, dating, stress, diet, and research.

 

 

“Origins of Cystic Fibrosis Lung Disease”

Origins of Cystic Fibrosis Lung Disease — NEJM (NEJM 2015; 372: 351-62) is a good read.  The authors note that the basic defect in Cystic Fibrosis (CF), the loss of the cystic fibrosis transmembrane conductance regulator (CFTR), has been recognized for a long time.  However, the connection between this defect and the progressive lung disease/inflammation has remained uncertain.

Now, new animal models have provided a wealth of information that closes the knowledge gap.

Here are the key points:

  • CF affects the lungs very early: Bronchiectasis is present in nearly one in three children with CF by 3 years of age and CT scans are abnormal in most babies with CF as early as 3 months of age.
  • Infection precedes inflammation: “During the first hours after birth, piglets with CF show no evidence of inflammation in their airways…yet,…they fail to eradicate bacteria as well…[which] can initiate a cascade of airway inflammation and airway remodeling.”
  • There are multiple “hits” on the airways.  While many have suggested that increased sodium leads to a ‘dehydrated’ state, this does not seem to be correct.
  • More recent studies point to loss of bicarbonate secretion as a crucial factor.  This results in a reduced pH which in turn leaves the lungs more vulnerable to infection.  Lower acidity reduces the effectiveness of a “complex soup of antimicrobial peptides, proteins, and lipids in airway-surface liquid.”
  • Poor mucociliary transport, “which guards the lungs by trapping invading pathogens and particulates in mucus,” is another important “hit” on the lungs.

Implications:

  • CF needs to be diagnosed early and treated early
  • Improving even one of these defects in host defenses is likely to be beneficial.
  • Animal models remain important in understanding pathophysiology.  They allow “investigating the disease at its genesis and before the onset of secondary manifestations.”

Related blog posts:

Progress in Cystic Fibrosis over 18 Years

A recent study (J Pediatr 2014; 165: 1091-7) showed significant improvement in lung function among 6-year-olds with Cystic Fibrosis (CF) between 1994-2012.

Using the Cystic Fibrosis Foundation Patient Registry with a total of 11,670 children, the authors found that the mean FEV1 and FVC z-scores increased significantly over the period in the entire cohort.  In addition, the height-for-age (HFA) also improved.  These results are easy to see graphically in Figures 1 & Figure 2.  The authors note that in 2012, children who were identified by screening had improved HFA, FEV1, and FVC compared to children who were not identified by screening.

Take-home points:

  • These data show impressive improvement in lung function and growth over the past two decades
  • These values are going to improve further now that all 50 states mandate newborn screening for CF
  • While there is improvement, 6-year-olds with CF still have measurable pulmonary dysfunction; thus, more work is needed, perhaps with novel therapies.

Related blog posts:

What We Know Now: Therapeutic Drug Monitoring for Inflammatory Bowel Disease

This blog has discussed the utility of obtaining drug levels for both biologic agents and thiopurines.  A recent article (Inflamm Bowel Dis 2015; 21: 182-97) provides a concise up-to-date review.

Here are the key points:

  • Primary nonresponse to anti-TNF therapy (PNR) “is most commonly defined as lack of improvement of clinical signs and symptoms after the induction phase leading to discontinuation of the drug.”
  • “We think that patients who respond but fail to achieve remission…are likely almost all due to insufficient drug.”
  • Table 2 provides a list of predicting factors, both negative and positive, for PNR.  This list includes genetic mutations (e.g.. IL23R, NOD2/CARD15 variant), mucosal gene expression, clinical factors (e.g. young age, isolated colitis, smoking, nonstricturing disease, concomitant immunomodulators) and serologic (eg. CRP, hemoglobin, and presence of pANCA).
  • Patients with PNR to a TNF antagonist, “despite therapeutic concentrations of drug and no anti-drug antibodies (ADA), would likely benefit from a switch to an alternative drug with a different mechanism of action.”
  • “Patients with a high baseline inflammatory load…and increased clearance of drug because of a high turnover would likely benefit from higher induction doses.”  This hypothesis has been proven in rheumatoid arthritis patients in which patients with high TNF concentrations had a clinical response to 10 mg/kg that was “significantly better than the response to 3 and 6 mg/kg of infliximab.”
  • Patients (with ADA) with an “early immunogenic response against the TNF antagonist are unlikely to respond to dose escalation and thus should be switched to another TNF antagonist, and it should be considered to give higher induction doses in combination with an IMM [immunomodulator] to reduce the risk of immunogenicity.”

Take-home message: New definition of primary nonresponse to anti-TNF agent: “a lack of improvement of objectively assessed signs of active inflammation at baseline, after the induction phase despite the presence of adequate concentrations of drug and the absence of anti drug antibodies.”

Also noted: “Surgical management of ulcerative colitis in the era of biologicals” Inflamm Bowel Dis 2015; 21: 208-10. Key point: “Sacrificing the non responsive diseased colon is an underused or unnecessarily delayed chance to normalize ..health and life.”  “Deconditioning of patient with unreasonably long escalations of ineffective medications adds to the morbidity of surgical intervention.”

“Automimmune Features are Associated with Chronic Antibiotic-refractory Pouchitis”Inflamm Bowel Dis 2015; 21: 110-20. Key point: “Microsomal antibody expression and elevated IgG4-positive plasma cell infiltration were independent risk factors” for chronic antibiotic-refractory pouchitis.”

Update on MOC (recent blog:Resistance to Maintenance of Certification | gutsandgrowth) American Board of Internal Medicine “We Got It Wrong” “We launched programs that weren’t ready and we didn’t deliver an MOC program that physicians found meaningful. We want to change that.”

Related blog posts:

“Using Drugs to Discriminate”

A recent commentary (Jacobs DB, Sommers BD, NEJM 2015; 372; 399-402) highlighted a growing problem.  Many insurers are using drug benefit plans to dissuade sicker people from enrolling in their plans.

Prior to the Affordable Care Act (ACA), insurers charged high premiums to people with chronic conditions.  The ACA attempted to address this problem; in fact, the “individual mandate” was necessary to make sure that insurance companies had enough healthy people in their insurance pool to make it financially feasible.

Yet, insurance companies make more money if they can limit insuring sicker, chronically-ill people.  One way this is happening is through “Adverse Tiering” which substantially increases out-of-pocket expenses for individuals with HIV, cancer, diabetes, mental illness, and arthritis. The difference in out-of-pocket costs, for example, with for each HIV drug was more than $3000 (on average) between adverse-tiered plans and those that were not adverse-tiered.  Even for generic drugs, the cost was nearly a $2000 difference.

A few problems with this approach:

  • Insurer’s drug prices are not usually available to public when choosing a plan; thus, these higher out-of-pocket costs are often unanticipated. (*Price transparency could accelerate rather than hinder this process.)
  • If sicker patients flock to plans without “adverse tiering,” this could make these non-adverse-tiered plans lose money and result in similar design to avoid “adverse selection.”

Conclusion: “Preventing [this adverse tiering and] other forms of financial discrimination on the basis of health status — with the attendant risks of adverse selection in the marketplace –will require ongoing oversight.”

Here’s the NY Times Report on this study: Study Finds HIV Drugs Priced Out of Reach

Related blog post:

 

Not So Promising: FMT for Ulcerative Colitis

After initial reports suggesting that fecal microbiota transplantation (FMT) may be helpful for ulcerative colitis (UC), more recent data suggest that it is not so promising (JPGN 2015; 60: 27-29, editorial 3).

In this open-label, prospective study of four patients, all boys aged 13-16 years, patients tolerated a single-dose FMT (via nasogastric tube) without adverse effects but there was no significant clinical or laboratory improvement.

The article provides a number of references regarding the experience of FMT for UC.

Related blog posts:

Which is Safer –Drip Feeds or Bolus Feeds in Healthy Preterm Infants?

A recent provocative study (J Pediatr 2014; 165: 1255-7) takes a look at the frequency of cardiorespiratory events in healthy neonates <33 weeks gestation who needed supplemental enteral tube feeds.

It is generally accepted that continuous or “drip” feedings are less likely to provoke reflux events (and reflux-induced cardiorespiratory events) by limiting the amount of formula in the stomach at any time point.  If there is less formula, presumably there would be less stomach distention and a lower likelihood of reflux.  In addition, a continuous amount of formula would serve to buffer stomach acid.

Despite the sound theoretical underpinnings, is this really true?  In this study, the authors detected fewer cardiorespiratory events with polysomnographic monitoring in healthy premature neonates who were fed with bolus feedings rather than with drip feedings.

Study design: Each of 33 infants served as its own control.  During a 6-hour monitoring period, noninvasive polysomnographic recordings were performed.  Each infant was fed twice via an orogastric tube.  The first meal was given as a 10-minute bolus (by gravity) and the second was delivered over 3 hours. It is noted that the tube was removed after the bolus feeding (this is not routinely done in clinical practice).

Demographics: Median gestational age was 31 weeks and median postnatal age was 16 days.  Fortified human milk was given in 12, premature formula in 7, and 14 had mixed feeding.

Results (Table 2): “continuous feeding was associated with a greater number of prolonged apneas and apnea-related hypoxic episodes.”

  • Median Apnea Frequency: 4 in continuous versus 2 in bolus group (no obstructive apneas were noted)
  • Median hypoxic episodes: 3 in continuous versus 2 in bolus group.

The authors speculate that leaving the tube in place for continuous feeds could increase GER-related apnea or trigger ‘protective upper airway reflexes in response to the irritating stimulus.’

Bottomline: The assumption that continuous feedings will reduce cardiorespiratory events is not supported by this study.  The findings warrant cautious interpretation; the small sample size and specific ages of the premature infants are significant limitations.   In addition, leaving an enteral tube in place after a bolus feeding would be a better design as this is a routine practice.

Related blog post:

Prucalopride -Not Better Than Placebo for Children with Constipation

Background: There were high expectations for prucalopride for the treatment of constipation based on previous small studies as well as a placebo-controlled trial in adults.  In adults, after 12 weeks of treatment, between 19.5-29% were responders compared to 9.6-12.1% in placebo patients. Prucalopride is a 5-hydroxytryptamine receptor-4  (5HT4) agonist which has been shown to accelerate colonic motility and is similar structurally to agents like cisapride and tegaserod; these latter medications have shown effectiveness as prokinetics but were limited by life-threatening cardiovascular side effects.

Design: Large (n=213), multicenter, placebo-controlled trial (Mugie SM, et al. Gastroenterol 2014; 147: 1285-95, editorial 1214-16). Response to medication indicated by >3 spontaneous bowel movements per week and <1 episode of fecal incontinence every 2 weeks.

Findings:

  • 17% of prucalopride subjects and 17.8% of placebo subjects were considered responders.
  • If based solely on bowel movement frequency, 29.2% of prucalopride achieved >3 BMs/week, whereas 35.5% of placebo-treated patients achieved this frequency.
  • Adverse effects were similar

Why did Prucalopride not work?

The authors and editorial make several speculations.  In children, withholding behavior is much more important in the pathophysiology of functional constipation (FC) than in adults.  In addition, slow transit constipation is much more common in adults than in children. In the adolescents (≥12 to <18) there was a mild response noted: 18.5% compared with 14.8% of placebo-treated patients (P=.38). The editorial notes that the short length of the trial (8 weeks) could explain the negative results, though this is unlikely.

The editorial, by Samuel Nurko and Miguel Saps, notes a much higher response to polyethylene glycol which “is the mainstay of treatment.”  “PEG-based solutions achieved a successful outcome in 56% of participants compared with 29% in the lactulose group.”

Take-home message: “This study does not provide new data to justify a change in the indication of PEG as first line of treatment for FC in children.”

In followup to questions regarding Miralax safety, here is a link from NASPGHAN’s Neurogastroenterology and Motility Committee: Miralax FAQ

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A Sign in Our Office --Needs Clarification

A Sign in Our Office –Needs Clarification