Breastfeeding and IQ -the Latest Data

A recent study (JY Bernard et al J Pediatr 2017; 183: 43-50) takes a look at the relationship between breastfeeding, specific polyunsaturated fatty acid (PUFA) levels and intelligence quotient at age 5-6 years.

The authors used the French EDEN cohort with 1080 children.

Key findings:

  • Breastfed children had higher IQs by 4.5 points on Wechsler Scales –though this dropped to 1.3 (not significant) when adjusted for confounders
  • DHA was positively associated with higher IQ.  Children exposed to colostrum high in linoleic acid (LA)/ow in docosahexaenoic acid (DHA) had lower IQs than those exposed to colostrum high in DHA/low LA

The authors speculate that one reason that supplemental DHA has not been shown to be effective could be related to a high intake of LA.

Related article: CT Collins et al. NEJM 2017; 376: 1245-55.  In this study, the authors showed that enteral supplemental of DHA (60 mg/kg) did not result in a lower risk of physiological bronchopulmonary dysplasia in a randomized trial of 1273 born before 29 weeks gestation.

Related blog posts:

With a new ballpark in town, there are a lot of firsts: first HR, first hit, etc. And now this

 

Selective Data Mining: Reflux and Bronchopulmonary Dysplasia

With some studies, the abstract may suggest a more compelling result than is truly evident.  That’s how I feel about a recent report (Nobile S, et al. J Pediatr 2015; 167: 279-85).

Here’s the conclusion (verbatim) from the abstract: “The increased number of (and sensitivity for) pH-only events among infants with BPD may be explained by several factors, including lower milk intake, impaired esophageal motility, and a peculiar autonomic nervous system response pattern.”

To me, it sounds like this prospective study of pH-multichannel intraluminal impedance (pH-MII) of 46 infants born ≤32 weeks gestation (12 with bronchopulmonary dysplasia (BPD) and 34 without BPD) must have identified something important linking gastroesophageal reflux disease (GERD) and BPD.  But, the real findings, in my view, are that this is a negative study. Period.

Here are the results reported in the abstract:

  • “Infants with BPD…had increased numbers of pH-only events (median number 21 v 9) and a higher symptom symptom sensitivity index for pH-only events (9% vs. 4.9%)”
  • They also state: “the number and characteristics of acid, weakly acid, nonacid and gas gastroesophageal reflux events, acid exposure, esophageal clearance, and recorded symptoms did not significantly differ between the 2 groups.”

Here’s a little more data –not in the abstract:

  • The P value for the difference in pH-only events was .360
  • The authors could just have easily pointed out (in the abstract) that infants without BPD had increased acid exposure: 40.5 min compared with 27.0 min (P = .599)

What should have been in the abstract conclusion? Perhaps, the first line of their discussion: “Infants with BPD did not have significantly higher GER features compared with infants without BPD as measured by esophageal pH-MII monitoring, except for higher occurrence of pH-only events and higher SSI for pH-only events.”

The authors try to explain the differences in the BPD patients by highlighting some of the potential mechanisms of reflux and/or autonomic dysfunction.  I think the limitations of this study deserve careful scrutiny.  This was a small study with only 12 BPD infants.  There was a significant selection bias -only ‘symptomatic’ infants were included.  Some of the factors affecting BPD directly could have an indirect effect on reflux (eg. caffeine).

The authors make one other point: “we believe pharmacologic treatment for GER should be initiated only after the demonstration of pathologic pH-MII monitoring to avoid unnecessary drug therapy, adverse events, and costs.”

Related blog posts:

Grand Prismatic Spring, Yellowstone

Grand Prismatic Spring, Yellowstone

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.