Bone Mineral Density and Dickkopf-1 in Adolescents with Non-deletional
Hemoglobin H Disease
Background: Low bone mineral density (BMD) is prevalent in
individuals with β-thalassemia which might be related to increased
circulating dickkopf-1 (Dkk-1). These data are limited in α-thalassemia.
Objectives: To evaluate the prevalence of low BMD in
adolescents with non-deletional hemoglobin (Hb) H disease. Additionally,
we aimed to examine the association between serum Dkk-1 concentration
and BMD. Methods: Participant medical records were reviewed.
The lumbar spine (LS) and total body (TB) BMD were measured and
converted into height-adjusted z-scores. Serum Dkk-1, osteocalcin and
C-telopeptide of type-I collagen (CTX) concentrations were also
analyzed. Results: Thirty-seven participants (59% female, 86%
Tanner stage ≥2, 95% regularly transfused) had mean age 14.6 ± 3.2
years, and average pretransfusion Hb and ferritin concentrations of 8.8
± 1.0 g/dL and 958 ± 513 ng/mL, respectively. No participants had
experienced fracture. The prevalence of low LSBMD and TBBMD was 42% and
17%, respectively. LSBMD z-score was lower in males vs. females
(p-value = 0.029). LSBMD and TBBMD z-scores were correlated positively
with BA, Tanner stage, and BMI, and negatively with Dkk-1 (p-values
<0.05). Dkk-1 was correlated positively with history of
delayed puberty, and negatively with transfusion interval (p-values =
0.038). Osteocalcin and CTX did not correlate with BMD or Dkk-1.
Multiple regression analysis showed Dkk-1 inversely associated with
TBBMD z-score adjusting for confounders (p-value = 0.009).
Conclusions: We demonstrated a high prevalence of low BMD in
adolescents with non-deletional Hb H disease. Moreover, Dkk-1 inversely
associated with TBBMD suggesting it may serve as bone biomarker in