title: Low bone mineral density in adolescents with beta-thalassemia.
abstract: The pervasiveness of low bone mass (LBM) in beta-thalassemia (Thal) patients (pts) is escalating as the average life expectancy of these pts increases. Adolescence is a period of substantial bone accrual, which is crucial for future bone strength. Studies of LBM are prevalent among adults with Thal. However, limited information exists about bone accrual and LBM in adolescents with the disease. Thirty-one pts with beta-Thal (26 Thal major [TM], 5 Thal intermedia [TI]), aged 9-20 years (mean: 15.3 years), 14 males and 17 females, underwent measurement of spinal bone mineral density (BMD) by DEXA (Lunar, Prodigy). Height, weight, body mass index, and Tanner stage were assessed at the time of the BMD measurement. A total of 16.1% of the patients had normal bone mass (Z > or = -1), 22.6% had reduced bone mass (Z = -1 to -2), and 61.3% had low bone mass (Z < or = -2). BMD Z correlated with height and weight Z scores. Some 53.9% of subjects had normal gonadal function and 46.1% had induced puberty with gonadal steroids. BMD Z significantly worsened with age (P < .0001). However, there was no difference in the LBM prevalence between subjects with normal versus those with induced puberty: BMD Z was -2 or less in 71.4% of subjects with normal puberty versus 66.7% in those with induced puberty. Our results indicate a high prevalence of LBM among adolescents with Thal regardless of adequate transfusion and chelation regimens. Bone accrual was found to be suboptimal in adolescents with normal or induced puberty. Thus, calcium and vitamin D supplementation with antiresorptive therapies should be evaluated in the adolescent Thal pt with close monitoring of growth and sexual development.
authors.affiliation: Department of Pediatrics, New York-Presbyterian Hospital / Weill Medical College of Cornell University, New York, New York 10021, USA.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Vogiatzi
authors.forename: Karen A
authors.initials: KA
authors.lastname: Autio
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Mait
authors.forename: Robert
authors.initials: R
authors.lastname: Schneider
authors.forename: Martin
authors.initials: M
authors.lastname: Lesser
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Giardina
mesh_terms: D000293:Adolescent; D000328:Adult; D000886:Anthropometry; D001803:Blood Transfusion; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000453:epidemiology / Q000209:etiology*; D015913:Chelation Therapy; D002648:Child; D003131:Combined Modality Therapy; D003676:Deferoxamine / Q000627:therapeutic use; D018450:Disease Progression; D004700:Endocrine System Diseases / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D005260:Female; D012739:Gonadal Steroid Hormones / Q000627:therapeutic use; D019382:Human Growth Hormone / Q000627:therapeutic use; D006801:Humans; D007006:Hypogonadism / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D007502:Iron Chelating Agents / Q000627:therapeutic use; D008297:Male; D010024:Osteoporosis / Q000453:epidemiology / Q000209:etiology*; D015995:Prevalence; D011628:Puberty, Delayed / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D013131:Spine / Q000737:chemistry; D017086:beta-Thalassemia / Q000150:complications*
chemical_list: D012739:Gonadal Steroid Hormones; D007502:Iron Chelating Agents; D019382:Human Growth Hormone; D003676:Deferoxamine