Volume 22, Number 3—March 2016
Research
Decreased Time to Treatment Initiation for Multidrug-Resistant Tuberculosis Patients after Use of Xpert MTB/RIF Test, Latvia
, Peter A. White, Vija Riekstiņa, Andra Cīrule, Ģirts Šķenders, Vaira Leimane1, Liga Kuksa1, Gunta Dravniece, James Brown, and Charlotte Jackson
Table 2
Univariate and multivariable accelerated failure time models of association between Xpert MTB/RIF use and time to MDR TB treatment initiation for patients in MDR TB treatment cohorts, Latvia, 2009–2012*
| Variable | Crude analysis, median days to diagnosis (95% CI) | Univariate regression |
Multivariable regression |
|||
|---|---|---|---|---|---|---|
| Median days to diagnosis | p value, time ratio (95% CI) | Median days to diagnosis | p value, time ratio (95% CI) | |||
| Overall |
24 (21–29) |
NA |
NA |
NA |
NA |
|
| Xpert MTB/RIF | ||||||
| Not conducted | 40 (33–45) | 38 | <0.001 | † | † | |
| Conducted, rifampin-resistant TB |
6 (5–7) |
NA |
0.19 (0.15–0.23) |
† |
† |
|
| Sex | ||||||
| M | 26 (21–30) | 30 | 0.08 | 30 | 0.08 | |
| F |
21 (11–30) |
NA |
0.80 (0.63–1.02) |
NA |
0.79 (0.62–1.02) |
|
| Age, y | ||||||
| <20 | 64 (2−‡) | 29 | 0.98 | 33 | 0.78 | |
| 20–39 | 21 (9–29) | NA | 1.00 (0.87–1.16) | NA | 0.98 (0.84–1.14) | |
| 40–59 | 28 (22–30) | NA | NA | NA | NA | |
| >60 |
30 (14–48) |
NA |
NA |
NA |
NA |
|
| Country of birth | ||||||
| Latvia | 26 (21–30) | 29 | 0.63 | NA | NA | |
| Other |
14 (8–29) |
NA |
0.91 (0.63–1.32) |
NA |
NA |
|
| Region of Latvia | ||||||
| Riga | 16 (11–24) | NA | 0.78 (0.63–0.96) | NA | 0.93 (0.75–1.16) | |
| Other |
30 (24–36) |
32 |
0.02 |
32 |
0.51 |
|
| Social risk factors | ||||||
| None or unknown | 30 (23–35) | 32 | 0.03 | NA | NA | |
| >1 |
22 (11–28) |
NA |
0.79 (0.65–0.97) |
NA |
NA |
|
| Previous TB | ||||||
| No | 24 (18–29) | 28 | 0.39 | † | † | |
| Yes |
27 (16–35) |
NA |
1.10 (0.89–1.36) |
† |
† |
|
| Site of disease | ||||||
| Pulmonary | 28 (23–31) | 30 | 0.01 | 30 | 0.05 | |
| Pulmonary and extrapulmonary |
7 (4–11) |
NA |
0.61 (0.43–0.86) |
NA |
0.69 (0.49–0.98) |
|
| HIV status | ||||||
| Negative | 29 (24–33) | 31 | 0.003 | NA | NA | |
| Positive | 7 (4–11) | NA | 0.59 (0.44–0.79) | NA | NA | |
| Unknown | 29 (14–48) | NA | 1.00 (0.71–1.43) | NA | NA | |
*Crude median time to MDR TB treatment initiation was determined (with a binomially derived CI), followed by association between use of Xpert MTB/RIF and time to treatment initiation in univariate and multivariable (372 patients) accelerated failure time models and median time to treatment in such models. Prisoners with MDR TB and persons with only extrapulmonary MDR TB were excluded; 15 patients with negative results by Xpert MTB/RIF were also excluded. Age was treated as a linear variable in regression analyses. The final regression model adjusted for all variables except country of birth, social risk factors, and HIV status. MDR TB, multidrug-resistant tuberculosis; MTB, Mycobacterium tuberculosis; RIF, rifampin; NA, not applicable.
†Stratified results are shown in Table 3.
‡No binomial prediction as small stratum.
1These authors contributed equally to this article.