CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

Poster and Themed Discussion Abstracts 681 BONE DENSITY, MICROARCHITECTURE, AND BONE STRENGTH AFTER 1 YEAR OF TDF Robert Güerri-Fernández 1 , Hernando Knobel 1 , Judit Villar 1 , Alicia González-Mena 1 , Ana Guelar 1 , Ludovic Humbert 2 , Elisabet Lerma-Chipirraz 1 , Marta Trenchs-Rodríguez 3 , Adolfo Díez-Pérez 1 1 Hosp del Mar, Barcelona, Spain, 2 Galgo Med, Inc, Barcelona, Spain, 3 CAP Passeig de Sant Joan, Barcelona, Spain Background: Bone mineral density (BMD) by dual-energy x-ray absorptiometry (DXA) measures the amount of mineral,but not other key aspects of bone strength such as bone microarchitecture or bone quality.Other techniques such as DXA-3D,Trabecular Bone Score (TBS)and in vivo microindentation directly measure cortical,trabecular microarchitecture and bone quality, respectively.These techniques provide a more comprehensive assessment of bone health in those situations where BMD is not fully capturing the decrease in bone strength,and thus,the risk of fracture. Methods: Longitudinal study with HIV naïve patients starting TDF based ART.BMD (DXA-Hologic) was measured at lumbar spine and hip.Spine trabecular microarchitecture was measured by TBS (Medimaps inc).DXA-3D was measured by a 3D-software (Galgo Medical, Spain) on the hip DXA quantifying the volumetric BMD (vBMD),bone volume and cortical thickness distribution.Microindentation were measured using a Osteoprobe (Active-Life-Scientific,CA) at the anterior tibial face. Results are expressed as bone material strength index (BMSi) units. The BMD,TBS,BMSi and DXA-3D measurements at baseline and 1 year after treatment were compared using paired samples Student’s t-test. Results: Forty-nine HIV patients were included.Changes in DMO(g/cm^2)were: lumbar spine (0.976±0.024vs0.947±0.024;p<0.001;-2.8%),total hip(0.936±0.026 vs 0.930±0.025;p=0.56;-0.3%) and femoral neck (0.829±0.251vs0.802±0.023;p<0.001;-2.9%) at baseline and after 1 year of TDF treatment respectively.When analyzing DXA-3D a statistically significant decrease of the integral vBMD (-11.9 mg/cm3,-3.0%,p=0.001) and cortical vBMD (-4.0 mg/cm3,-0.4%,p=0.004) was observed at the femoral neck. The cortex at the neck was also significantly thinner after 1-year of treatment (-0.05 mm, -3.2%,p=0.006)with significantly significant difference for the trabecular vBMD.A significant reduction of TBS was observed (1.359±0.016vs1.322±0.01; p=0.0059; -2.5%).With microindentation,the BMSi was significantly higher (85.5±1.1 vs 88.5±1.2;p= 0.03; +3.8%),showing better bone strength after 1 year of treatment with TDF. Conclusion: A decrease in trabecular and cortical microarchitecture at spine and hip was observed after 1 year of TDF therapy. However,tissue quality seemed to recover after 1 year of TDF,following the control of HIV infection.These techniques provide additional information to DXA about bone health in HIV patients.Due to its convenience and feasibility the role of them should be evaluated in future studies.

CROI 2017 296