Factors Associated with Low-Level Viraemia and Virological Failure: Results from the Austrian XXXX Cohort Study.

@entity1 @entity177 @entity258 @entity645
BACKGROUND: In @entity1 immunodeficiency virus treatment adequate virological suppression is warranted, nevertheless for some @entity1 it remains a challenge. We investigated factors associated with @entity258 ( @entity258 ) and @entity177 ( @entity177 ) under combined antiretroviral therapy (cART). MATERIALS AND METHODS: We analysed @entity1 receiving standard regimens between 1st July 2012 and 1st July 2013 with at least one viral load (VL) measurement below the quantification limit (BLQ) in their treatment history. After a minimum of 6 months of unmodified cART, the next single VL measurement within 6 months was analysed. @entity177 was defined as @entity645 RNA levels >= 200 copies/mL and all other quantifiable measurements were classified as @entity258 . Factors associated with @entity258 and @entity177 compared to BLQ were identified by logistic regression models. RESULTS: Of 2276 @entity1 , 1972 (86.6%) were BLQ, 222 (9.8%) showed @entity258 and 82 (3.6%) had @entity177 . A higher risk for @entity258 and @entity177 was shown in @entity1 with cART interruptions and in @entity1 with boosted PI therapy. The risk for @entity258 and @entity177 was lower in @entity1 from centres using the Abbott compared to the Roche assay to measure VL. A higher risk for @entity258 but not for @entity177 was found in @entity1 with a higher VL before cART [for >99.999 copies/mL: aOR (95% CI): 4.19 (2.07-8.49); for 10.000-99.999 copies/mL: aOR (95% CI): 2.52 (1.23-5.19)] and shorter cART duration [for <9 months: aOR (95% CI): 2.59 (1.38-4.86)]. A higher risk for @entity177 but not for @entity258 was found in younger @entity1 [for <30 years: aOR (95% CI): 2.76 (1.03-7.35); for 30-50 years: aOR (95% CI): 2.70 (1.26-5.79)], @entity1 originating from high prevalence countries [aOR (95% CI): 2.20 (1.09-4.42)] and in male injecting drug users [aOR (95% CI): 2.72 (1.38-5.34)]. CONCLUSIONS: For both @entity177 and @entity258 , factors associated with adherence play a prominent role. Furthermore, performance characteristics of the diagnostic assay used for VL quantification should also be taken into consideration.
