2-NBDG To identify factors associated with being HCV unaware
To identify factors associated with being HCV-unaware, univariable and multivariable logistic model were used, odds ratios, 95% confidence intervals and p-values were reported. We included in the multivariable model factors associated with unawareness of HCV infection in univariable analysis with a p-value less than 0.1. Values of p<0.05 were considered statistically significant. All statistical analyses were conducted using StataCorp 2013. Stata Statistical Software: Release 13. College Station, TX: StataCorp LP.
Results From January 2004 to December 2015, 3563 individuals were newly diagnosed with HIV: 636 (17.8%) lacking anamnestic and/or serologic information on HCV infection within 3 months of HIV diagnosis were excluded from the analysis. Of the 2927 HIV positive persons included in the analysis, 250 resulted anti-HCV positive with an overall prevalence rate of 8.5% (Fig. 1). The rate of anti-HCV positivity decreased significantly over time being 15.3% in 2004–2006, 8.8% in 2007–2009, 7.4% in 2010–2012 and 4.5% in 2013–2015 (p<0.001 by chi-square for trend). No significant trends over time in anti-HCV prevalence were observed stratifying by mode of infection (Fig. 2). HCV RNA testing within 3 months of HIV diagnosis was available for 181 HCV-positive individuals, and 143 (79.0%) were viremic. Among the anti-HCV positive persons, 40 (16.0%) had a FIB-4 score≥3.25 indicative of advanced liver fibrosis, while for 17 (6.8%) laboratory data to calculate the score were not available within three months from diagnosis. Among the persons with a FIB-4 score, 22 (9.4%) had a platelet count below 100×109/L. Among 105 persons who reported a previous diagnosis of HCV infection, the median time from HCV to HIV diagnosis was 9.6years (Interquartile range [IQR]: 4.1–14.5). Sixteen (15.2%) of them did not report any HIV-negative test and, they 2-NBDG eventually resulted HIV-positive a median of 8.4 years (IQR: 3.1–14.8) from HCV positivity. Overall, 145 anti-HCV positive persons (58.0%) were unaware of their serostatus at the time of HIV diagnosis. A FIB-4 score≥3.25 was recorded for 25 (17.2%) HCV-unaware individuals and, among the 104 HCV-unaware individuals for whom HCV RNA was available, 85 (81.7%) tested positive. The proportion of HCV-unaware individuals did not show significant variations over time (Table 1). At univariable analysis, the probability of being HCV-unaware was higher among those with a late HIV diagnosis, among those who did not have a previous HIV negative test as well as among those without this information, and among those who did not have a previous diagnosis of sexually-transmitted infections (STI) or did not report this information. HBV coinfection was detected in 51.2% of persons and no differences emerged between HCV-unware and HCV-aware. No association were found by gender, place of birth, place of living, risk factors for HIV acquisition and FIB-4 score. Moreover, no significant differences in the prevalence of HCV viremia were observed (Table 1). Among those with positive viremia, the median HCV RNA level detected did not differ comparing HCV-aware and unaware persons (640,402; IQR: 190,548–2,234,779 vs 1,044,649; IQR: 260,857–3,199,032 respectively, p=0.256; Mann–Whitney test). The most widespread HCV genotype, classified in 116 persons, was type 1 (53.9%) while type 3 was present in 22.4%, type 4 in 16.4% and type 2 in 3.4%. These proportions did not vary according to HCV awareness (data not shown).
Discussion Over a 12-year period, we recorded a 70.6% decrease in prevalence of anti-HCV positivity, among persons with newly diagnosed HIV infection. This observation is consistent with the decreasing trend of HCV prevalence recorded among persons entering HIV care in Italy, and may partly reflect a decrease in the proportion of injecting drug users among newly diagnosed HIV infections . We observed that more than half of newly diagnosed persons were unaware of their positive HCV serostatus before HIV diagnosis, and this proportion was stable over time. This evidence, taken together with other studies , , may suggest the existence of a sizeable population of persons with undiagnosed coinfection in high-income countries.