Factors associated with TB incidence after cART initiation
| Univariate model | Final adjusted model | |||||
|---|---|---|---|---|---|---|
| IRR | 95% CI | p* | IRR | 95% CI | p* | |
| Risk group | <0.001 | 0.002 | ||||
| Sex between men | 1 (ref) | 1 (ref) | ||||
| Sex between men and women | 1.67 | (1.07 to 2.61) | 1.58 | (0.78 to 3.21) | ||
| Injecting drug users | 3.34 | (2.17 to 5.15) | 4.26 | (2.18 to 8.33) | ||
| Other/unknown | 0.85 | (0.27 to 2.75) | 1.05 | (0.24 to 4.59) | ||
| Geographical origin | 0.008 | 0.031 | ||||
| Mid–low TB incidence† | 1 (ref) | 1 (ref) | ||||
| High–mid TB incidence‡ | 1.91 | (0.93 to 3.93) | 2.14 | (0.76 to 5.99) | ||
| Very high TB incidence: sub-Saharan Africa | 1.90 | (0.89 to 4.15) | 2.69 | (0.95 to 7.64) | ||
| Unknown | 0.56 | (0.33 to 0.94) | 0.42 | (0.17 to 1.08) | ||
| Duration of HIV infection at cART initiation (years) | 1.03 | (0.98 to 1.07) | 0.241 | 1.01 | (0.93 to (1.09) | 0.869 |
| Current CD4 count | <0.001 | <0.001 | ||||
| ≥500 | 1 (ref) | 1 (ref) | ||||
| 350–499 | 1.89 | (1.00 to 3.58) | 1.69 | (0.74 to 3.84) | ||
| 200–349 | 2.58 | (1.38 to 4.83) | 2.24 | (0.97 to 5.18) | ||
| <200 | 15.4 | (9.24 to 25.5) | 11.57 | (5.58 to 23.96) | ||
| Nadir CD4 count at cART initiation | 0.011 | 0.109 | ||||
| ≥500 | 1 (ref) | 1 (ref) | ||||
| 350–499 | 1.04 | (0.53 to 2.03) | 1.12 | (0.74 to 3.84) | ||
| 200–349 | 1.19 | (0.69 to 2.04) | 1.77 | (0.97 to 5.18) | ||
| <200 | 2.02 | (1.23 to 3.32) | 2.64 | (0.74 to 3.84) | ||
| Time-weighted average CD4 at cART initiation | 0.031 | 0.4316 | ||||
| ≥500 | 1 (ref) | 1 (ref) | ||||
| 350–499 | 0.85 | (0.53 to 1.38) | 0.52 | (0.21 to 1.14) | ||
| 200–349 | 1.31 | (0.83 to 2.07) | 0.71 | (0.29 to 1.72) | ||
| <200 | 2.05 | (1.19 to 3.54) | 0.60 | (0.18 to 1.99) | ||
| HIV-RNA at cART initiation (1 log increase) | 1.16 | (1.04 to 1.29) | 0.006 | 1.118 | (1.04 to 1.33) | 0.007 |
| Current age (10-year increase) | 1.01 | (0.83 to 1.22) | 0.941 | |||
| Sex | 0.269 | |||||
| Men | 1 | |||||
| Women | 1.26 | (0.84 to 1.90) | ||||
| Calendar year at cART initiation | 0.586 | |||||
| <2001 | 1 | |||||
| ≥2001 | 0.9 | (0.60 to 1.35) | ||||
*Wald test for heterogeneity when variable is categorical. Multivariable Poisson model for the association of TB risk and past and current level of immunosuppression (current CD4 count, nadir and time weighted average CD4 count and duration of HIV infection at cART initiation) adjusted for risk group, geographical origin and HIV-RNA at cART initiation.
†Mid–low incidence regions: Western Europe, North America, Oceania, Middle East and Latin America.
‡High–mid incidence regions: Eastern Europe, Central Asia, North Africa, South Asia, East Asia and the Caribbean.
cART, combination antiretroviral therapy; IRR, incidence rate ratio; TB, tuberculosis.