Читать книгу Nutrition and Growth - Группа авторов - Страница 23

Kao KT¹, Joseph S^1,2, Capaldi N¹, Brown S², Di Marco M^2,3, Dunne J², Horrocks I², Shepherd S¹, Ahmed SF¹, Wong SC¹

¹Developmental Endocrinology Research Group, Royal Hospital for Children, Glasgow, UK; ²Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK; ³Scottish Muscle Network, Queen Elizabeth University Hospital, Glasgow, UK

Eur J Pediatr 2019:178:633–640

Background: Boys with Duchenne muscular dystrophy (DMD) are treated with long term high dose oral glucocorticoid from approximately 4–5 years, and continued to adulthood. As a result, severe growth failure and short stature are commonly seen. Significant obesity is also a problem in paediatric DMD especially at the time of loss of ambulation. Small studies in children with hemiplegic cerebral palsy showed that lower leg length maybe present. The aim of the study is to evaluate body proportions in boys with DMD treated with GC.

Methods: Thirty boys with DMD on glucocorticoid therapy were compared with 30 healthy aged matched children (matched to within 6 months) recruited locally. Body segments and total height were measured using dual energy absorptiometry (DXA) total body images performed on Lunar Prodigy DXA scanner. Results were reported as median (range).

Results: All boys with DMD have been on oral glucocorticoid for a duration of 7.1 years (1.3 to 15.2). Height Z-score was significantly lower in boys with DMD compared with controls (p < 0.0001) and body mass index Z-score was significantly higher (p < 0.0001). Fifty seven percent of controls where pre-pubertal whereas 87% of boys with DMD were pre-pubertal. Height of boys with DMD was 10.7 cm (95% CI –17.1 to –4.3) lower than healthy controls after adjusting for pubertal status. Median percentage difference of sitting height in boys with DMD compared with controls was 6.5% lower (range –24 to +6.7%), whereas median percentage difference of leg length in boys with DMD in comparison with controls was 13% lower (range –46 to +13%). Median percentage difference in femur length in DMD compared with controls was 12% lower (range –41 to +19%) and median percentage difference in tibial length in DMD compared to controls was 23% lower (range –53 to +9.4%). Similarly, greater reduction of distal long bone of the upper limb was also observed in boys with DMD.

Conclusion: Boys with DMD on glucocorticoid therapy had evidence of skeletal disproportion with relatively shorter leg length and greater reduction in distal long bones. The underlying aetiology of this skeletal disproportion is currently unclear.

Unmodified reproduction. This work is licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/deed.en)

Comments

Glucocorticoid excess is not known to be associated with skeletal disproportion, although there are hardly any studies in any childhood chronic condition of glucocorticoid excess. This study utilized a method of evaluating body proportions and bone lengths using DXA total body images and opens up the opportunity to evaluate stature and bone lengths in children with immobility. Previous studies show that short stature is relatively common in boys with Duchenne muscular dystrophy (DMD) even prior to treatment with glucocorticoid when these boys are still ambulant (approximately 25% with height Z-scores lesser than –2.0). The authors raise the possibility of an inherent growth disorder associated with DMD. Obesity is a common occurrence in DMD especially during childhood and in those on glucocorticoid therapy. The interaction of obesity and nutritional intake on linear growth, stature, and body proportions should be studied in future research.

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