Monitoring growth can serve as an early warning for many childhood diseases, but a lack of consensus on how tracking should work and what to look for may mean diagnosis is delayed for some and wrong for others, a recent research review suggests.
It may seem simple in theory to look at how children’s height and weight compare to that of other kids their age and then search for medical reasons why some of them might, for example, be unusually short.
But first, doctors need to agree on what constitutes abnormal growth – and they don’t – researchers note in their January 14 online paper in The Lancet Diabetes and Endocrinology.
“Growth-monitoring is widely used in most countries in the world,” lead researcher Pauline Scherdel of INSERM in Paris said by email. “However, we have found strong empirical evidence showing that the current practices are suboptimal – diagnostic delays in one hand and unnecessary diagnostic work-up in the other hand.”
Researchers examined 69 previously published studies, which compared the performance of growth charts from the World Health Organization (WHO) to other growth charts and looked at seven different algorithms for defining abnormal growth that have been proposed in the past 20 years.
They also explored which conditions might be spotted by monitoring growth charts and how abnormal development should be defined.
While dozens of diseases may be potential causes of abnormal growth, researchers found most previous research focused on six conditions: Turner syndrome, celiac disease, cystic fibrosis, growth hormone deficiency, renal tubular acidosis and small for gestational age with no catch-up after two or three years.
Even though there was some consensus that these diseases are among the ones that should be considered when kids don't grow like their peers, the analysis found little evidence that the seven algorithms used to define abnormal growth proposed in earlier studies were effective.
Two studies reported that WHO growth charts had poorer performance compared with other existing growth charts for early detection of target conditions.
One study from the Netherlands found as many as 95% of referrals for tests to detect problems based on abnormal growth didn't turn up anything, suggesting there were unnecessary screenings being done in healthy children, the authors conclude.
Two clinical decision tools – the Grote and Saari methods – appeared to be the most promising of the bunch because they were highly specific in detecting Turner syndrome and celiac disease, the authors concluded. The Grote clinical decision rule also appeared specific enough to detect cystic fibrosis.
Among other things, the Grote and Saari methods both relied on observation of standardized height, distance to standardized target height, and height deflection (a reduced growth rate indicated by adjusted height over time).
Limitations of the study include its reliance on published studies, which may not accurately reflect what doctors do in day-to-day practice to track how children grow, the authors note.
Finding the best way to use growth as an early warning for childhood disease is important because this has the potential to be a low-cost and simple way to identify kids who may have health problems that are negatively impacting their development, Dr. Jana Vignerova, a researcher at the National Institute of Public Health in Prague who wasn't involved in the study, said by email.
"Growth charts are a single, cheap and non-invasive tool, Vignerova said. "Other methods are more expensive and mostly invasive, such as blood tests, X-rays and other examinations."
