Time of Progression to Osteopenia/Osteoporosis in Chronically HIV-Infected Patients: Screening DXA Scan

et al. (2012) Time of Progression to Osteopenia/Osteoporosis in Chronically HIV-Infected Patients: Screening DXA Scan. PLoS ONE 7(10): e46031. doi:10.1371/journal.pone.0046031 Time of Progression to Osteopenia/Osteoporosis in Chronically HIV-Infected Patients: Screening DXA Scan Eugenia Negredo 0 Anna Bonjoch 0 Moise s Go mez-Mateu 0 Carla Estany 0 Jordi Puig 0 Nuria Perez- 0 Alvarez 0 Joaquin Rosales 0 Silvana di Gregorio 0 Luis del Rio 0 Guadalupe Go mez 0 Bonaventura Clotet 0 Songtao Shi, University of Southern California, United States of America 0 1 Lluita contra la SIDA Foundation, Hospital Universitari Germans Trias i Pujol, Universitat Auto` noma de Barcelona , Barcelona , Spain , 2 Statistics and Operations Research Department, Universitat Polite`cnica de Catalunya , Barcelona, Spain, 3 CETIR Centre Me`dic, Barcelona, Spain, 4 Irsicaixa Foundation, Barcelona , Spain Background: Algorithms for bone mineral density (BMD) management in HIV-infected patients are lacking. Our objective was to assess how often a dual-energy x-ray absorptiometry (DXA) scan should be performed by assessing time of progression to osteopenia/osteoporosis. Methods: All DXA scans performed between 2000 and 2009 from HIV-infected patients with at least two DXA were included. Time to an event (osteopenia and osteoporosis) was assessed using the Kaplan-Meier method. Strata (tertiles) were defined using baseline minimum T scores. Differences between strata in time to an event were compared with the logrank test. Results: Of 391 patients (1,639 DXAs), 49.6% had osteopenia and 21.7% osteoporosis at their first DXA scan. Of the 112 (28.6%) with normal BMD, 35.7% progressed to osteopenia; median progression time was 6.7 years. These patients were stratified: ''low-risk'' (baseline minimum T score .20.2 SD), ''middle-risk'' (between 20.2 and 20.6 SD), and ''high-risk'' (from 20.6 to 21 SD); median progression time to osteopenia was 8.7, .7.2, and 1.7 years, respectively (p,0.0001). Of patients with osteopenia, 23.7% progressed to osteoporosis; median progression time was .8.5 years. Progression time was .8.2 years in ''low-risk'' tertile (T score between 21.1 and 21.6 SD), .8.5 years in ''middle-risk'' (between 21.6 and 22), and 3.2 years in ''high-risk'' (from 22 to 22.4) (p,0.0001). Conclusions: Our results may help to define the BMD testing interval. The lowest T score tertiles would suggest recommending a subsequent DXA in 1-2 years; in the highest tertiles, $6 years. Early intervention in patients with bone demineralization could reduce fracture-related morbidity/mortality. - Funding: This work was supported in part by a grant from the Spanish Ministry of Education and Science [Grant number MTM2008-06747-C02-00]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. No additional external funding was received for this study. Competing Interests: The authors have declared that no competing interests exist. Bone strength is the result of bone mineral density (BMD) and bone microarchitecture. A decrease in BMD leads to deterioration of microarchitecture, and is determined by the intensity of bone remodeling. These changes lead to critical damage and porosity that weaken bone and increase the probability of fractures.[1] Many factors lead to accelerated bone loss, and HIV infection is one of the most recently identified [2,3,4]. The results of several studies confirm a higher incidence of osteopenia and osteoporosis in HIV-infected patients than in HIV-negative individuals. In fact, up to 25% of infected patients fulfill the criteria for osteoporosis and up to 50% fulfill those of osteopenia [2,3,4,5]. Accelerated bone demineralization in this population is due to an additional number of factors such as the HIV infection itself and the chronic inflammatory status, by increasing apoptosis of osteoblast cells and promotion of osteoclastic activity [6,7,8,9,10,11,12,13,14,15], the exposure to specific antiretroviral agents [2,13,16,17,18] and the immune reconstitution [14,19,20], together with traditional risk factors, such as vitamin D insufficiency, a secondary cause of osteoporosis that is very prevalent among HIV-infected patients. [21] In addition, the first available longitudinal studies revealed that HIV-infected patients experience more rapid bone loss [5,19,20] and more frequent fractures than HIV-negative individuals. [20,22,23,24] The high associated morbidity and mortality of bone fractures [25] means that optimal monitoring of bone mineralization should be offered to patients at high risk of low BMD, such as the HIVinfected population. Dual-energy X-ray absorptiometry (DXA) is the method of choice for the assessment of BMD. Most clinicians attending HIVinfected patients agree that this group should undergo DXA screening, especially those patients with traditional risk factors for bone loss. [26,27] However, the optimal BMD testing intervals remains undetermined. This study aims to determine how often a DXA scan should be performed in chronically HIV-infected patients by assessing the time of progression to osteopenia or osteoporosis in a large cohort. Study design, population, and objective We performed a retrospective longitudinal observational study of all DXA scans from HIV-infected patients who attended our HIV Unit between January 2000 and December 2009. Of a total of 671 patients with at least one DXA scan, 391 had at least two DXA scans performed during the study period. These scans were included in the present analysis. The study was performed according to the stipulations of the Declaration of Helsinki, and all patients gave their written informed consent for their medical information to be used for purposes of scientific research in accordance with the ethical committee of the participating site. A more detailed description of the methodology applied has been described elsewhere. [2] The objective of the study was to determine the time of progression to bone loss defined as time from normal BMD to osteopenia and from osteopenia to osteoporosis. Osteopenia and osteoporosis were defined following the World Health Organization (WHO) criteria, as follows: normal, when the T score by DXA was higher than 21.0 SD, osteopenia when the T score was between 21.0 SD and 22.5 SD, and osteoporosis when the T score was less than 22.5 SD. [28] Assessments A total of 1,639 DXA scans from 391 patients were included in the present analysis. The mean BMD and T score (comparison with normal reference values for young adults expressed as standard deviation units) for the lumbar spine and femoral neck were measured using the same DXA device (Lunar Prodigy, GE Healthcare, Belgium) at an external center (CETIR Grup Me`dic, Barcelona, Spain). Epidemiological and HIV-related data (time since diagnosis of HIV infection, time on antiretroviral treatment, viral load, CD4 T-cell count, nadir CD4 T-cell count, total t (...truncated)