Assessment of nutritional status and bone health in neurologically impaired children: a challenge in pediatric clinical practice.

Introduction: neurologically impaired children frequently experience nutritional disorders and bone health complications. Our aim was firstly to analyze a method to interpret bone mineral density (BMD) accurately in neurologically impaired children. Secondly, to determine its relationship with the nutritional status and micronutrient levels in order to identify which factors are associated with low BMD. Methods: a observational multicenter study was conducted in children with moderate-to-severe neurological impairment. Data collected included: medical records, anthropometric measures, hematologic and biochemical evaluation. BMD was measured with Dual-energy X-ray absorptiometry and z-scores were calculated adjusting for sex and chronological age. Secondly, BMD z-scores were calculated applying height age (age at which the child's height would be in 2nd percentile) instead of chronological age. Results: fifty-two children were included (aged 4-16 years). Seventeen patients (32.7%) received feeding by gastrostomy tube. Height and BMI z-score were below 2SD in 64% and 31% of patients respectively, with normal mid upper arm circumference and skinfold thickness measurements. Low vitamin-D levels were found in 42% of cases. 50% of patients evidenced low BMD when calculated for chronological age, whereas only 34.5% showed BMD z-score <-2 when calculated for height age. No correlation was observed between BMD and vitamin-D levels, weight and height z-scores or age when BMD was calculated applying height age. Conclusions: the prevalence of low BMD is high in neurologically impaired children, and it is probably multifactorial. In these children, we suggest adjusting BMD for height age, in order not to over diagnose low BMD.