Objective: To compare changes over 48 weeks in bone mineral density (BMD) between participants randomized to lopinavir/ritonavir (LPV/r) + raltegravir (RAL) or LPV/r + 2–3 nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) as second line therapy.
Design: 48-week open-label sub-study of the Second Line trial conducted in South Africa, India, Thailand, Malaysia and Argentina.
Methods: Dual energy X-ray absorptiometry scans of proximal femur and lumbar spine were performed at baseline and week 48. Linear regression was used to compare means of differences between arms. McNemars test compared osteopenia and osteoporosis. Associations between percentage BMD changes and baseline variables were assessed by multivariate linear regression.
Results: Two hundred and ten participants were randomized. Analyses were adjusted for sex, BMI and smoking status. Mean (95% CI) proximal femur BMD% reduced over 48 weeks by −5.2% (−6.7 to −3.8%) in the LPV/r+2-3N(t)RTIs arm and by −2.9% (−4.3 to −1.5%) in the LPV/r+RAL arm (P = 0.0001). Lumbar spine BMD reduced by −4.2% (−5.7 to −2.7%) in the LPV/r+2-3N(t)RTIs arm and by −2.0% (−3.5 to −0.6%) in the LPV/r+RAL arm (P = 0.0006). The incidence of osteopenia (7.6%) and osteoporosis (2.0%) assessed over 48 weeks were similar between arms. Reduced BMD over 48 weeks was significantly associated with longer duration of tenofovir on study [% change (SE) −1.58 (0.38) femur, −1.65 (0.38) spine, P = 0.0001] and low baseline BMI [% change (SE) 0.5 (0.13) femur, 0.17 (0.07) spine; P < 0.01].
Conclusion: An N(t)RTI-sparing antiretroviral regimen of LPV/r and raltegravir as second line therapy is associated with less bone loss than a LPV/r regimen containing N(t)RTIs.
aThe Kirby Institute, University of New South Wales, Sydney, Australia
bUCD School of Medicine and Medical Science, Dublin, Ireland
cThe Alfred Hospital, Melbourne, Australia
dCICAL, Buenos Aires, Argentina
eThai Red Cross AIDS Research Center, Bangkok, Thailand
fHopital Saint-Louis, Paris, France.
Correspondence to Allison Martin, The Kirby Institute, University of New South Wales, Sydney, NSW 2052, Australia. Tel: +61 2 9385 0900; fax: +61 2 9385 0910; e-mail: email@example.com
This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivitives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. http://creativecommons.org/licenses/by-nc-nd/3.0.
Received May 6, 2013
Accepted June 25, 2013