Bone health measures in glucocorticoid-treated ambulatory boys with Duchenne muscular dystrophy.
Osteoporosis is a major problem in boys with Duchenne Muscular Dystrophy (DMD), attributable to muscle weakness and glucocorticoid therapy. Consensus regarding bone health assessment and management is lacking. Lumbar spine areal bone mineral density (defined as bone mass per area of bone) by dual-energy X-ray absorptiometry (DXA) is frequently the primary measure used, but has limitations for boys with DMD. We retrospectively studied 292 ambulant glucocorticoid-treated boys with DMD categorized by functional mobility score, FMS 1, 2 or 3. We assessed DXA whole body and lumbar spine areal bone mineral density and content Z-scores adjusted for age and height, lateral distal femur areal bone mineral density Z-scores, frequency of fractures, and osteoporosis by International Society for Clinical Densitometry 2013 criteria. Whole body and femoral DXA indices decreased, while spine fractures increased, with declining motor function. Lumbar spine areal bone mineral density Z-scores appeared to improve with declining motor function. Bone mineral content Z-scores were consistently lower than corresponding bone mineral density Z-scores. Our findings highlight the complexity of assessing bone health in boys with DMD. Bone health indices worsened with declining motor function in ambulant boys, but interpretation was affected by measure and skeletal site examined. Whole body bone mineral content may be a valuable measure in boys with DMD. Lumbar spine areal bone mineral density Z-score as an isolated measure could be misleading. Comprehensive management of osteoporosis in boys with DMD should include vertebral fracture assessment.
Division of Neurology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA; University of Cincinnati College of Medicine, 2600 Clifton Avenue, Cincinnati, OH 45220, USA.
Cuixia
C
Tian
Division of Neurology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA; University of Cincinnati College of Medicine, 2600 Clifton Avenue, Cincinnati, OH 45220, USA.
Brenda L
BL
Wong
Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA.
Lindsey
L
Hornung
University of Cincinnati College of Medicine, 2600 Clifton Avenue, Cincinnati, OH 45220, USA; Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA; Division of Endocrinology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA.
Jane C
JC
Khoury
Department of Psychological Sciences, University of Connecticut, 406 Babbidge Road, Storrs, CT 06269, USA.
Lauren
L
Miller
Division of Neurology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA.
Jean
J
Bange
Division of Neurology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA.
Irina
I
Rybalsky
University of Cincinnati College of Medicine, 2600 Clifton Avenue, Cincinnati, OH 45220, USA; Division of Endocrinology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA. Electronic address: meilan.rutter@cchmc.org.
Meilan M
MM
Rutter
D015502:Absorptiometry, Photon; D000293:Adolescent; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D004185:Disability Evaluation; D018450:Disease Progression; D050723:Fractures, Bone / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D005938:Glucocorticoids / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology*; D009465:Neuromuscular Agents / Q000009:adverse effects / Q000627:therapeutic use*; D010024:Osteoporosis / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D012189:Retrospective Studies; D016138:Walking
D005938:Glucocorticoids; D009465:Neuromuscular Agents
Bone mineral content; Bone mineral density; Dual-energy X-ray Absorptiometry (DXA); Fracture; Osteoporosis; Steroid