CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

645 VITAMIN D METABOLITES AND MORTALITY RISK AMONG HAART-TREATED HIV-INFECTED MEN

Long Zhang 1 , Todd Brown 1 , Joseph B. Margolick 1 , Sabina Haberlen 1 , Mallory Witt 2 , Frank J. Palella 3 , Lawrence Kingsley 4 , Andrew Hoofnagle 5 , Lisa Jacobson 1 , Alison Abraham 1 1 The Johns Hopkins Univ, Baltimore, MD, USA, 2 Los Angeles Biomed Rsr Inst at Harbor–UCLA Med Cntr, Torrance, CA, USA, 3 Northwestern Univ, Chicago, IL, USA, 4 Univ of Pittsburgh, Pittsburgh, PA, USA, 5 Univ of Washington, Seattle, WA, USA Background: Low serum 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) levels are associated with increased all-cause mortality risk in the general population. However, little is known about these associations in HAART-treated HIV-infected individuals. Methods: The MACS vitamin D ancillary study quantified 25(OH)D and 1,25(OH)2D levels from stored samples 1-3.5 years after HAART initiation from 1996-2013 in 641 HIV- infected men. Standardized 25(OH)D and 1,25(OH)2D levels were divided into quartiles, and the highest quartile was compared to lower three quartiles. Men contributed follow-up time from the date of the vitamin D metabolite measurement to death or to 31 March 2016. Cox proportional hazards models were used to evaluate the relationship between vitamin D levels and all-cause mortality or non-AIDS mortality risk with adjustment for covariates. The analysis was also stratified by plasma HIV viral load (VL) suppression status. Results: Of the 641 men studied, 425 were VL suppressed and 261 were VL unsuppressed at baseline. 60%were white; 75%were former or current smokers; 8%were HCV- infected; 32% had hypertension. Median age, CD4+ T cell count, and VL of participants were 44 years (IQR: 39-50), 512 cells/µL (IQR: 344-695) and <50 copies/mL (IQR: <50-129), respectively. The median 25(OH)D was 22.2 ng/mL (IQR: 16.2-28.3) and that for 1,25(OH)2D was 46.4 pg/mL (IQR: 37.1-56.0). The median follow-up was 12 years (IQR: 8-16), with 96 deaths (15%) observed: 46 AIDS-related, 10 cardiovascular, 11 from cancer, and 29 from other diseases or unknown causes. All-cause mortality did not differ across quartiles of 25(OH)D. In contrast, those with high 1,25 (OH)2D at baseline had reduced all-cause mortality compared to those in the lower three quartiles of 1,25 (OH)2D among VL-suppressed men at baseline (HR=0.25, P=0.022), but not among VL-unsuppressed men (HR= 0.90, P=0.774; interaction P=0.050). High 1,25(OH)2D levels were marginally associated with decreased risk of non-AIDS mortality among VL suppressed men (HR= 0.16, P=0.078), but not among VL unsuppressed men (HR=0.25, P=0.204; interaction P=0.575). Conclusion: High levels of 1,25(OH) 2 D, but not of the more commonly measured 25(OH)D, were associated with lower all-cause and non-AIDS-related mortality risk among virologically suppressed HIV-infected men. Further studies are needed to determine if 1,25(OH) 2 D levels have utility as a prognostic indicator of mortality risk in this population.

Poster and Themed Discussion Abstracts

CROI 2017 276