People being treated for tuberculosis achieved virologic and CD4 responses to antiretroviral therapy (ART) similar to people not being treated for TB, according to results of a 25-study systematic review and meta-analysis.
Although clinical trials confirm the benefit of starting ART promptly in people being treated for TB, early ART does raise the risk of immune reconstitution inflammatory syndrome. To get a better understanding of the impact of TB therapy on response to ART, researchers conducted a systematic review of studies reporting HIV RNA and CD4 count response in people receiving or not receiving TB therapy.
The 25 cohort studies eligible for analysis included 49,578 adults (range 42 to 15,646 per study), of whom 8826 (18%) were receiving TB therapy when they began ART. The analysis included 17 studies of virologic response and 21 studies of CD4-cell response.
Summarized random-effects relative risk (RRRE) of virologic suppression in adults receiving versus not receiving TB therapy showed no substantial difference between the two groups at 1 to 4 months of ART (1.06, 95% confidence interval [CI] 0.86 to 1.29), at 6 months (0.91, 95% CI 0.83 to 1.00), at 11 to 12 months (0.99, 95% CI 0.94 to 1.05), or at 18 to 48 months (0.99, 95% CI 0.77 to 1.28).
The overall RRRE from 1 to 48 months of ART was 0.97 (95% CI 0.92 to 1.03), a result indicating that TB therapy has no important impact on response to ART. Thirteen studies assessing the impact of TB therapy on virologic failure were heterogeneous and inconclusive.
In 7 studies the impact of TB therapy on CD4 count in the first 6 months of ART ranged from −10 to 60 cells/μL (median 27). In 5 studies the impact of TB therapy on CD4 count after 11 to 12 months of ART ranged from −10 to 29 cells/μL (median 6). The heterogeneity of response measures in these studies did not permit meta-analysis.
“Patients receiving TB treatment at cART initiation experience similar virologic suppression and CD4+ cell count reconstitution as those not receiving TB treatment,” the researchers conclude, a result “reinforcing the need to start cART during TB treatment and allowing more confidence in clinical decision-making.”
The World Health Organization recommends starting ART regardless of CD4 count in people with active TB. For people with HIV and active TB, WHO advises that “antituberculosis treatment should be initiated first, followed by ART as soon as possible within the first 8 weeks of treatment.”
Source: Heidi M. Soeters, Sonia Napravnik, Monita R. Patel, Joseph J. Eron, Annelies Van Rie. The effect of tuberculosis treatment on virologic and CD4+ cell count response to combination antiretroviral therapy: a systematic review. AIDS. 2014; 28: 245-255.