The prevalence of patients with positive HCV antibodies among those

tested in a given calendar year decreased from 50% in 1998 to 30% in 2008, while for HBV surface antigens the prevalence slightly decreased from 7 to 6%. In the analysis of patients grouped by treatment status, there was a significant increasing trend over time in the relative frequency of patients receiving ART for at least 6 months by increasing calendar years (from 29% in 1998 to 58% in 2008; P<0.0001), a decrease in the proportion of those treated for less than 6 months (from 22 to 12%; P<0.0001), and a decrease in the proportion of patients who were still selleck inhibitor ART-naïve at the end of the year (from 45 to 25%; P<0.0001). For patients in treatment interruption, there was a bell-shaped trend increasing from 4% in 1998 to 11% in 2004 and decreasing to 6% in 2008. The trend over time in the proportion of patients with a CD4 count ≤200 cells/μL was analysed overall and after stratifying I-BET-762 concentration by treatment status and mode of HIV transmission.

A decrease in the proportion of patients with CD4 count ≤200 cells/μL was seen, from 14% in 1998 to 6% in 2008 [relative risk (RR)=0.94; 95% CI 0.93–0.95; P<0.0001 per more recent year, after fitting a univariable Poisson regression]. Figure 1 (left panel) shows the proportion of patients with a poor immunological prognosis across calendar years and stratified by mode of transmission or ART status. The overall prevalence of low CD4 cell counts (the estimate of the intercept in the model) was the highest in IDU (11%) and other modes of HIV transmission (12%), intermediate in patients infected via heterosexual contact (8%) and lowest in patients infected Ponatinib via homosexual/bisexual

contact (6%). Differences in the overall proportions by mode of transmission were highly significant (P<0.0001). When we stratified by ART status, the highest proportion of poor prognosis was seen in patients previously treated for <6 months (16%), followed by those on treatment interruption (13%), those previously on ART for ≥6 months (7%), and those previously naïve to treatment (7%). The differences in the overall proportion among these groups were statistically significant (P<0.0001). Table 2a shows the adjusted RRs of having a CD4 count ≤200 cells/μL associated with mode of transmission, use of ART and all other patient characteristics after fitting the multivariable Poisson regression model. The factors independently associated with a significantly lower risk of a CD4 count ≤200 cells/μL were: calendar year, having acquired HIV via homosexual/bisexual contact vs. heterosexual contact, a higher nadir CD4 count, and living in the north of Italy compared with central Italy. In contrast, older age, positive vs. negative HCV Ab, any other ART status vs.