Showing posts with label growth. Show all posts
Showing posts with label growth. Show all posts

Monday, November 24, 2014

Postnatal Growth Following Prenatal Lead Exposure and Calcium Intake

By: Assistant Editor Lydia Furman, MD

Photo by F. Lamiot via Wikimedia Commons (edited)
Lead is a ubiquitous environmental toxin, with well appreciated deleterious effects on the neurodevelopment of young children. But what do we know about the physical growth of lead-exposed infants and children? Dr. Hong and colleagues prospectively examine the effect of maternal lead levels during early and late pregnancy on postnatal growth at birth and at 6, 12 and 24 months (doi: 10.1542./peds.2014-1658).

Lead does cross the placenta, so prenatal exposure clearly has potential to reach the developing fetus; however there is limited evidence to date of any impact on postnatal growth beyond the neonatal period (Schell et al, Am J Human Bio, 2009).

Certainly no lead level is considered “safe.” With a new focus on primary prevention, the CDC has established 5.0 micrograms/dL or greater as the lead level that identifies children who are in the highest 2.5 percent of US children based on the National Health and Nutrition Examination survey (NHANES) data on blood lead levels in children.

Previously the CDC used a “level of concern” of 10 micrograms/dL; however it became clear that even at these “low” levels there were negative effects on neurodevelopment as assessed at 24 months with the Bayley Scales of Infant Development (Tellez-Rojo et al, Pediatrics, 2006), on intelligence as assessed at age 6 years (Canfield et al, New England Journal of Medicine, 2003 and Jusko et al, Environmental Health Perspectives, 2007), and on reading readiness at kindergarten entry (McLaine et al, Pediatrics, 2013). With the new population-based 2.5 percentile level of 5.0 micrograms/dL, clinicians, public health departments and parents hope to have the opportunity to intervene earlier and prevent deleterious effects.

But with less than 5.0 micrograms/dL as a non-actionable level for children, any direct effect of prenatal lead levels higher than this on child growth would be surprising. Hong and colleagues studied a cohort of 1,150 pregnant women whose mean lead level of 1.25 micrograms/dL was actually much lower.  Their unexpected results are a call to action for public health servants, policy makers and child advocates.

The authors further asked whether dietary intake of calcium has any impact on lead’s effects, and measured women’s diets carefully using dietary interviewers and 24 hour recall. Mothers’ mean daily calcium intake at study entry was 541 mg/24 hours; when pregnancy dietary intake of calcium was below the mean, this intensified the negative effect of maternal lead levels on infant growth, particularly birth weight.

The authors make a convincing case for biological plausibility of both the interrelationship between maternal dietary calcium intake during pregnancy and maternal blood lead levels, and the consequent demonstrated effect on infant growth. This article sets the stage for additional public health work, both to promote increased dietary calcium during pregnancy, and to continue the fight to reduce exposure of mothers and children to environmental toxins, including lead.

Tuesday, November 11, 2014

BMI Changes Between Fifth and Tenth Grades

By: Lewis First, MD, MS; Editor-in-Chief 

School lunch. Photo by US Dept. of Agriculture via Flickr
We have certainly published studies on overweight or obese toddlers and preschoolers with the hope of intervening as early as possible to attenuate the increasing weight gain—but what happens to weight gain and BMI in pre-adolescent children as they enter and move through adolescence? Does weight gain get worse or better? Can you influence the trajectory of that weight gain in this age group as much as if you altered things in early childhood?

Schuster et al. (doi: 10.1542/peds. 2014-2195) studied the factors that can result in progression to obesity as well as BMI reduction factors in a cohort of fifth graders followed through tenth grade. Those fifth graders who already had a negative body image due to their being overweight or obese, lower socioeconomic status, and/or an obese parent had the most difficulty lowering their BMI as they moved through adolescence.

What’s worse—fifth graders who were not yet overweight but had a negative body image of themselves, combined with an obese parent and/or a sedentary television-watching lifestyle were on a pathway to increasing their BMI trajectory unless intervening actions could be taken.

If you are interested in learning more as to what factors enhance or inhibit a child from becoming overweight or obese between fifth and tenth grade so you can better counsel your patients accordingly, this study weighs in admirably for your consideration.

You would be a pound foolish not to read it—if you want to work with your overweight or obese teens to lower elevated BMIs. And speaking of lowering BMIs in teens—have you found some ways to do this that yield success in your practice? Share your thoughts: leave a comment below, send us an eLetter on our journal website, or find us on Facebook or Twitter.

Related Reading:

Monday, October 27, 2014

Why You Should be Thinking About Fetal Alcohol Spectrum Disorders in Your Practice

By: Lewis First, MD, MS; Editor-in-Chief 

Diagnosing someone with a fetal alcohol spectrum disorder (FASD) is easier said than done. The findings can be subtle and might be easily missed unless you uncover clues in the family history or are aware of the constellation of dysmorphology findings that can be associated with this disorder.

Sometimes there is a sense that a fetal alcohol spectrum disorder is a rarer entity than it actually is—and thus you need not worry about missing something unlikely to occur. Alternatively, you may figure it will eventually declare itself anyway if a child develops progressive development delay or another less subtle finding prompting a more careful diagnostic approach.

Yet the prevalence of fetal alcohol spectrum disorders appears to be more common than we might hope—at least according to a representative sample of children examined at ages 6 to 7 in the Midwest US as studied by May et al. (doi:10.1542/peds.2013-3319).

Figure showing final estimate of FASD prevalence in a Midwestern US city.
Copyright 2014 © American Academy of Pediatrics. Used with permission.

The researchers selected their sample simply on the basis of their being below the 25th percentile for height, weight, and head circumference. This interesting study also includes a discussion of the risk factors that might point you towards diagnosing this disorder sooner.

If you need a refresher on ways to identify fetal alcohol syndrome so you can diagnose and implement early intervention services sooner rather than later, this is the study for you.

Related Reading: 

Tuesday, September 30, 2014

The Role of Parenting & Home Stimulation in Overcoming Cognitive Deficits in Bangladesh

By: Lewis First, MD, MS; Editor-in-Chief 

Bangladeshi children. Photo by Mahmud Rassel via Flickr
Poverty certainly takes its toll on children's health given the association between poverty and cognitive deficit in infancy, but is it possible to improve this deficit with environmental and parental influence?

The answer is a resounding yes according to Hamadani et al. (doi: 10.1542/peds.2014-0694) who performed a longitudinal study of development in more than 2,800 infants in Bangladesh. They followed these infants for IQ changes over their first five years of life as impacted by such factors as parental education and home stimulation by parents. The results are impressive and stress the import of such factors in a way that can be generalizable to our own young patients born into poverty in this country.

To share even more lessons learned from this study, we invited Dr. Andrew Racine (doi: 10.1542/peds.2014-1375) to comment in an accompanying editorial that we are also early releasing this week.

Both the study and commentary are rich in take-aways that will be useful to you and the underserved families you care for.

Related Reading:

Friday, September 5, 2014

ADHD, Stimulant Treatment and Stunted Growth: Just a Tall Tale?

Photo by Woodleywonderworks via Flickr
By: Lewis First, MD, MS; Editor-in-Chief 

Do parents of your patients tell you they worry the stimulant medications being used on their child with attention deficit hyperactivity disorder (ADHD) may affect his or her growth—or so they have read on the internet? Well, stand tall and show these families the new study by Harstad et al. (doi: 10.1542/ peds.2014-0428).

The authors looked at a population–based birth cohort from 1976 through 1982 and identified 340 ADHD cases on stimulant medication and 680 controls. They followed these children into adulthood and monitored their height velocities longitudinally as well as their final adult heights.

There is good news: researchers noted no association with differences in adult height or changes in growth velocity, reinforcing the idea that concerns about growth are far more fiction than fact—at least as per this study.

Do you agree? Have you seen other data that suggests there is an effect? Share your thoughts on this growing controversy by leaving a comment, submitting an eLetter to our journal or by joining in the discussion on Facebook or Twitter.

Related Reading:

Monday, August 25, 2014

Parental Perceptions of Overweight 20 Years Ago and Today: The Times (and BMIs) They Are a Changin’!

By: Lewis First, MD, MS; Editor-in-Chief 

Photo by epSos.de via Flickr
Part of the problem of trying to get a family to help their overweight child lose weight is getting parental buy-in—and that begins when parents agree that their child is medically perceived to be overweight. One would think that parents would view their child as being overweight quite easily—and while that may have been true 20 years ago—it is not as easily perceived today—at least according to a study we are sharing this week by Hansen et al. (doi: 10.1542/peds.2014-0012).

The authors looked at survey data from parents on close to 3,000 children (ages 6-11 years) enrolled in the National Health and Nutrition Examination Survey in 1988 through 1994 and another cohort enrolled in 2005 to 2010 and found some substantive differences. Parents today are less likely to perceive their child as overweight: They did not view weight gain above the 85th percentile but below the 91st percentile as concerning, whereas 20 years ago it was.

What does this shift in social norms mean for the health of children who are showing increased body weight and crossing high percentiles on a growth curve? Weigh in on the information contained in this study and then perhaps share it with parents of overweight patients and see if it can’t help them realize that their child’s increasing BMI over time really is a problem.

Related Reading:

Tuesday, September 10, 2013

Two Studies on Cerebral Palsy Advance Our Knowledge of Children with This Disorder

Children with cerebral palsy (CP), while often requiring input from neurologic, orthopedic, rehabilitative or other specialists, also need to have their longitudinal care needs coordinated and met by the medical home established by their primary care pediatrician.  Thus, the more we can learn about the longitudinal trajectory of these patients, the more we can be poised to initiate appropriate supportive services as needed to maintain and enhance the quality of life in these patients.  It is for this reason that we are sharing two studies this week that provide some new insight on the natural history of children with cerebral palsy.

The first study by Vohr et al. (doi: 10.1542/peds.2012-3915) examines growth failure along with cognitive impairment up to 6-7 years of age in children who experienced severe hypoxic ischemic encephalopathy (HIE) in early infancy.  They report results of growth parameters and neurodevelopmental status in 115 of 122 infants surviving in a hypothermia trial for neonatal HIE.  The results demonstrate a need to closely monitor growth in these patients and adjust nutritional needs and other treatments that may help prevent the lower percentiles of growth in these patients from occurring as well as perhaps improve cognitive outcomes.

The second study by Vos et al. (doi: 10.1542/peds.2013-0499) looked at the mobility performance of more than 400 patients with CP ages 1-20 years in terms of their ability to perform daily activities of life over time based on their gross motor function with or without intellectual disability.  Both gross motor function and intellectual disability play particular roles in mobility performance and/or daily activity performance, which in turn can affect the implementation of appropriate rehabilitation strategies.

If you follow a child with CP, both these articles provide insight into the long-term management you need to consider in enhancing the quality of life for these patients.  Read them both and learn more that can, in turn, be shared with the families of your CP patients.