THU419 Comprehensive Evaluation Of Osteoporosis And Impaired Bone Micro Architecture In Patients With Transfusion Dependent Beta Thalassemia

Abstract

Abstract Disclosure: P. Dutta: None. comprehensive evaluation of osteoporosis and impaired bone micro architecture in patients with transfusion dependent beta thalassemia Authors: Pinaki Dutta, Liza Das, Alka Khadwal, Pankaj Malhotra, Sanjay Kumar Bhadada, Vandana Dhiman, Vivek Sharma, Raman Introduction: Thalassemia-related bone disease is an entity that includes low bone mass, fractures and impaired bone microarchitecture. The current study was designed to evaluate the prevalence and determinants of low bone mass, osteoporosis and microarchitectural parameters using high-resolution peripheral quantitative computed tomography (HR-pQCT) in patients with transfusion-dependent thalassemia (TDT). Patients and Methods TDT patients (n=42) and age- and BMI-matched controls (n=40) were recruited. Demographic, biochemical and hormonal parameters were assessed. Bone mineral density (BMD), T- and Z- scores were measured by DEXA using the HOLOGIC Discovery A Viewer 6 machine. Bone microarchitecture was estimated by HR-pQCT (XtremeCT II, Scanco Medical AG, Switzerland). Results: The mean age of thalassemia patients at recruitment was 26.9 ± 6.5 years and that of controls was 28.9 ± 7.9 years. The mean age of transfusion initiation was 7 months (IQR 3-18) and the median number of transfusions required was 24 (15-25) annually. Serum calcium in cases (8.87 ± 0.67mg/dl) was significantly lower than the controls (9.40 ± 0.45mg/dl), with 9 patients having hypocalcemia and 7 of these having hypoparathyroidism. Hypogonadism was present in 40.4% patients. Bone turnover markers (P1NP, β-CTX) were not significantly different between cases and controls, except alkaline phosphatase (ALP) which was higher in the cases (102.6 ± 60.7 U/l) as opposed to controls (78.2 ± 32.1 U/l). There was a significant correlation between ALP and liver dysfunction (alanine transaminase exceeding the upper normal limit) (r = 0.36, p=0.01) and 63.6% of those with elevated ALP had liver dysfunction. Low bone mass (Z ≤−2) was present in significantly greater proportion of patients versus controls at femoral neck (29.3% vs 2.4%) and at lumbar spine (52.4% vs 14.7%). Total, cortical and trabecular volumetric bone mineral density were significantly lower in cases as compared to controls(p<0.05). The trabecular number was significantly lower (p<0.0001) and trabecular separation significantly higher at radius and tibia (p<0.001). Cortical thickness at radius and tibia were also significantly lower in cases than controls (p<0.0001). Conclusion: Patients with transfusion-dependent thalassemia have significantly lower areal and volumetric BMD (both cortical and trabecular). The bone microarchitecture is also significantly impaired in terms of lower number and wider spacing of trabeculae as well as lower cortical thickness at both radius and tibia. Presentation: Thursday, June 15, 2023