Background: People with HIV are at increased risk of low trauma fractures (LTFs). Published data on LTF incidence trends over time has not been uniform. This study sought to analyze LTF time trends in the Swiss HIV Cohort Study (SHCS) 2009-2022.

Methods: Fractures are prospectively captured in the SHCS. Since 2008, using a standardized form, each fracture and its low trauma nature was validated by the treating HIV physician and the main investigators. Applying negative binomial regression, we estimated the LTF incidence rate ratio per calendar year univariably and adjusting for time-updated clinical and HIV-related risk factors, plus a genome-wide polygenic risk score associated with bone mineral density.

Results: Between 2009 and 2022, 7524 SHCS participants accumulated 71983 participant-years of observation and 235 validated LTFs, for a LTF incidence of 0.33 (95% confidence interval [CI], 0.29-0.37) per 100 participant-years. There were statistically significant changes over time in multiple demographic, clinical and HIV-related variables potentially associated with better bone health. The LTF incidence rate declined 9.2% (95%CI, 5.6-12.6%) per year on average in univariable analysis and by 7.5% (95%CI, 2.9-11.9%) per year in the full multivariable model. Declining LTF time trends were noted in men and women, younger and older age groups, and participants with favorable and unfavorable genetic background.

Conclusion: LTFs have considerably decreased in people with HIV in Switzerland over a 14-year period. The LTF decline likely is multifactorial and occurred concomitant with favorable trends in ART, demographic and lifestyle variables that may contribute to better bone health.