Effect of different SLDs and their combination on survival of MDR/XDRTB patients*
| Variable | Unadjusted | Adjusted | ||
| HR (95% CI) | p Value | HR (95% CI) | p Value | |
| Effect of individual drugs† | ||||
| FQ | 0.55 (0.47 to 0.63) | <0.001 | 0.55 (0.47 to 0.63) | <0.001 |
| INJ | 0.76 (0.65 to 0.88) | <0.001 | 0.82 (0.70 to 0.97) | 0.016 |
| ETH/PT | 0.48 (0.41 to 0.55) | <0.001 | 0.49 (0.43 to 0.57) | <0.001 |
| CS | 0.60 (0.51 to 0.69) | <0.001 | 0.66 (0.56 to 0.76) | <0.001 |
| TRD | 0.89 (0.33 to 2.39) | 0.82 | 0.79 (0.29 to 2.14) | 0.65 |
| PAS | 0.74 (0.59 to 0.94) | 0.012 | 0.86 (0.68 to 1.09) | 0.21 |
| AMC | 0.84 (0.21 to 3.39) | 0.81 | 1.06 (0.26 to 4.40) | 0.94 |
| THZ | 8.49 (1.19 to 60.60) | 0.033 | 5.89 (0.82 to 42.19) | 0.079 |
| Effect of combinations of drugs‡ | ||||
| No SLDs | 1.00 | <0.001 | 1.00 | <0.001 |
| INJ only (group 2) | 0.69 (0.17 to 2.76) | 1.58 (0.39 to 6.48) | ||
| FQ only (group 3) | 0.75 (0.37 to 1.52) | 0.83 (0.41 to 1.68) | ||
| ETH/PT or PAS or TRD or CS only (group 4) | 0.45 (0.30 to 0.66) | 0.42 (0.28 to 0.62) | ||
| Groups 2 and 3 | 0.78 (0.40 to 1.52) | 0.82 (0.42 to 1.61) | ||
| Groups 2 and 4 | 0.40 (0.30 to 0.53) | 0.43 (0.32 to 0.57) | ||
| Groups 3 and 4 | 0.36 (0.30 to 0.44) | 0.36 (0.30 to 0.43) | ||
| Groups 2, 3 and 4 | 0.39 (0.32 to 0.47) | 0.42 (0.35 to 0.52) | ||
| Groups 3, 4 and other | 0.24 (0.03 to 1.74) | 0.32 (0.04 to 2.38) | ||
| Groups 2, 3, 4 and other | 1.03 (0.14 to 7.38) | 1.29 (0.18 to 9.49) | ||
| ETH/PT only | 0.31 (0.17 to 0.59) | 0.37 (0.20 to 0.71) | ||
| TRD or CS only | 1.73 (0.43 to 6.95) | 0.98 (0.23 to 4.19) | ||
↵* Values are HRs and CIs from a Cox proportional hazards regression: unadjusted results are not adjusted for any confounders; adjusted results are adjusted for MDR versus XDRTB, primary versus acquired, sex, age, rural/urban residence, contact with TB, smoking, alcohol use, drug abuse, homelessness, unemployment, education level, HIV status, co-morbidity, TB type, smear positivity and cavitary disease.
↵† Each drug analysed in a separate regression.
↵‡ Results of a single regression analysis with patients divided into 12 subgroups according to drug combination.
AMC, Amoxicillin/clavulanate; CS, Cycloserine; ETH/PT, Ethionamide/Prothionamide; FQ, Fluoroquinolones; INH, isoniazid; INJ, Injectables; MDR/XDRTB, multidrug- and extensively drug-resistant tuberculosis; PAS, P-aminosalicyclic acid; RIF, rifampicin; SLD, second-line drugs; THZ, Thiacetazone; TRD, Terizidone.