title: Fractures after antiretroviral initiation.
abstract: BACKGROUND
  Bone mineral density declines by 2-6% within 1-2 years after initiation of antiretroviral therapy (ART); however, it is uncertain whether this results in an immediate or cumulative increase in fracture rates.
  
  
  METHODS
  We evaluated the incidence and predictors of fracture in 4640 HIV-positive participants from 26 randomized ART studies followed in the AIDS Clinical Trials Group (ACTG) Longitudinal-Linked Randomized Trial study for a median of 5 years. Fragility and nonfragility fractures were recorded prospectively at semiannual visits. Incidence was calculated as fractures/total person-years. Cox proportional hazards models evaluated effects of traditional fracture risks, HIV disease characteristics, and ART exposure on fracture incidence.
  
  
  RESULTS
  Median (interquartile range) age was 39 (33, 45) years; 83% were men, 48% white, and median nadir CD4 cell count was 187 (65, 308) cells/μl. Overall, 116 fractures were reported in 106 participants with median time-to-first fracture of 2.3 years. Fracture incidence was 0.40 of 100 person-years among all participants and 0.38 of 100 person-years among 3398 participants who were ART naive at enrollment into ACTG parent studies. Among ART-naive participants, fracture rates were higher within the first 2 years after ART initiation (0.53/100 person-years) than subsequent years (0.30/100 person-years). In a multivariate analysis of ART-naive participants, increased hazard of fracture was associated with current smoking and glucocorticoid use but not with exposure to specific antiretrovirals.
  
  
  CONCLUSIONS
  Fracture rates were higher within the first 2 years after ART initiation, relative to subsequent years. However, continuation of ART was not associated with increasing fracture rates in these relatively young HIV-positive individuals.
authors.affiliation: Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA. Mty4@columbia.edu
authors.forename: Michael T
authors.initials: MT
authors.lastname: Yin
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Kendall
authors.forename: Xingye
authors.initials: X
authors.lastname: Wu
authors.forename: Katherine
authors.initials: K
authors.lastname: Tassiopoulos
authors.forename: Marc
authors.initials: M
authors.lastname: Hochberg
authors.forename: Jeannie S
authors.initials: JS
authors.lastname: Huang
authors.forename: Marshall J
authors.initials: MJ
authors.lastname: Glesby
authors.forename: Hector
authors.initials: H
authors.lastname: Bolivar
authors.forename: Grace A
authors.initials: GA
authors.lastname: McComsey
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000163:Acquired Immunodeficiency Syndrome / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000009:adverse effects*; D015992:Body Mass Index; D015519:Bone Density / Q000187:drug effects*; D018791:CD4 Lymphocyte Count; D005260:Female; D005500:Follow-Up Studies; D050723:Fractures, Bone / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology; D005938:Glucocorticoids / Q000009:adverse effects*; D006679:HIV Seropositivity / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D013997:Time Factors
chemical_list: D019380:Anti-HIV Agents; D005938:Glucocorticoids