Bone and fractures

Background

Several other studies, not related to the POPPY project, have reported that PLWH are more likely to experience fractures (broken bones) than similarly aged people without HIV.  It has been proposed that some ART drugs may contribute by leading to a loss of bone density.  HIV infection (and immunosuppression) may also play a role, leading to more rapid bone loss but less rapid bone growth.  Equally, we know that as people age their bones start to lose strength and that there are other factors (e.g. some recreational drugs, hepatitis C virus coinfection, smoking etc.) which may also contribute to weakened bones.  Thus, the increased fracture rate that has been seen in other studies may simply be a reflection of these factors.

Study aims

We are studying whether HIV status is independently associated with a reduction in bone mineral density at the three most commonly assessed sites (the lumbar spine, femoral neck and hip), once we have taken into consideration several other factors, including social and demographic factors, information on medications received, hepatitis virus coinfection and laboratory markers that are known to be associated with bone loss and fractures.  We will also study the associations between bone mineral density and recent fractures reported at the baseline POPPY visit, as well as with the risk of new fractures over the two years of the study.  Finally, we will investigate changes in bone mineral density in all POPPY participants to investigate whether PLWH appear to lose bone density at a more rapid rate than similarly aged HIV-negative people.

Work to date

Almost 1300 people in the POPPY study have had a DXA scan at their baseline visit, providing detailed information on bone mineral density.  Our initial findings suggest that HIV does continue to lead to a drop in bone mineral density, even after adjusting for other factors that have previously been shown to affect this.

Next steps

We are continuing to analyse the bone mineral density data and will next look at the associations between this and the fractures that were reported at the baseline POPPY visit.

Study group

Aoife Cotter (University College Dublin), Paddy Mallon (University College Dublin), Manolis Bagkeris (UCL), Caroline Sabin (UCL), Frank Post (Kings College Hospital), Alan Winston (Imperial College London).  Contact Caroline Sabin (c.sabin@ucl.ac.uk)