Volume 19, Number 5—May 2013
CME ACTIVITY - Research
Transmission of Mycobacterium tuberculosis Beijing Strains, Alberta, Canada, 1991–2007
Table 2
Case-patient characteristics associated with clustering of Beijing and non-Beijing Mycobacterium tuberculosis lineages, Alberta, Canada, 1991–2007
Characteristic | All cases | No. (%) clustered cases | OR (95% CI)* |
|
---|---|---|---|---|
Unadjusted | Adjusted† | |||
Beijing | ||||
Sex | ||||
F | 100 | 19 (19.0) | 1.0 | |
M | 158 | 36 (22.8) | 1.3 (0.7–2.3) | |
Age at diagnosis, y | ||||
<35 | 72 | 17 (23.6) | 1.0 | 1.0 |
35–64 | 69 | 19 (27.5) | 1.2 (0.6–2.6) | 1.3 (0.6–2.8) |
>64 | 117 | 19 (16.2) | 0.6 (0.3–1.3) | 0.7 (0.3–1.5) |
Population group | ||||
Canadian-born | 19 | 7 (36.8) | 1.0 | |
Foreign-born, other | 26 | 6 (23.1) | 0.5 (0.1–1.9) | |
Foreign-born, Western Pacific | 213 | 42 (19.7) | 0.4 (0.2–1.1) | |
Sputum smear status | ||||
Negative | 132 | 26 (19.7) | 1.0 | |
Positive | 112 | 25 (22.3) | 1.2 (0.6–2.2) | |
Bacillary load | ||||
Low | 38 | 7 (18.4) | 1.0 | |
High | 16 | 6 (37.5) | 2.7 (0.7–9.8) | |
Chest radiography | ||||
No cavitation | 206 | 40 (19.4) | 1.0 | 1.0 |
Cavitation | 52 | 15 (28.8) | 1.7 (0.8–3.4) | 1.6 (0.8–3.2) |
Drug resistance | ||||
Pan-susceptible | 202 | 42 (20.8) | 1.0 | |
Monoresistance | 30 | 7 (23.3) | 1.2 (0.5–2.9) | |
Polyresistance | 20 | 6 (30.0) | 1.6 (0.6–4.5) | |
Multidrug resistance |
6 |
0 |
NA |
|
Non-Beijing | ||||
Sex | ||||
F | 492 | 168 (34.1) | 1.0 | 1.0 |
M | 629 | 250 (39.7) | 1.3 (0.98–1.6) | 1.1 (0.8, 1.4) |
Age at diagnosis, y | ||||
<35 | 319 | 134 (42.0) | 1.0 | 1.0 |
35–64 | 421 | 182 (43.2) | 1.1 (0.8–1.4) | 0.8 (0.5–1.1) |
>64 | 381 | 102 (26.8) | 0.5 (0.4–0.7) | 0.4 (0.3–0.6) |
Population group | ||||
Canadian-born | 520 | 316 (60.8) | 1.0 | 1.0 |
Foreign-born, other | 346 | 42 (12.1) | 0. 1 (0.06–0.13) | 0.09 (0.06–0.13) |
Foreign-born, Western Pacific | 255 | 60 (23.5) | 0.20 (0.14–0.28) | 0.21 (0.15–0.31) |
Sputum smear status | ||||
Negative | 517 | 198 (38.3) | 1.0 | |
Positive | 538 | 199 (37.0) | 0.9 (0.7–1.2) | |
Bacillary load | ||||
Low | 177 | 67 (37.9) | 1.0 | |
High | 89 | 39 (43.8) | 1.3 (0.8–2.1) | |
Chest radiography | ||||
No cavitation | 853 | 312 (36.6) | 1.0 | |
Cavitation | 268 | 106 (39.6) | 1.1 (0.9–1.5) | |
Drug resistance | ||||
Pan-susceptible | 1,000 | 393 (39.3) | 1.0 | 1.0 |
Monoresistance | 90 | 19 (21.1) | 0.4 (0.2–0.7) | 0.6 (0.4–1.1) |
Polyresistance | 25 | 5 (20.0) | 0.4 (0.1–1.04) | 0.7 (0.3–2.1) |
Multidrug resistance | 6 | 1 (16.7) | 0.3 (0.04–2.7) | 0.5 (0.05–5.0) |
*Boldface indicates significance (p<0.05). OR, odds ratio.
†Multivariate analysis was based on purposeful selection with variables with p<0.2 in unadjusted analyses being included in the multivariate model. For Beijing strains, multivariate analysis included the independent variables of age at diagnosis and chest radiography. Sex, age at diagnosis, population group, and drug resistance were the independent variables in the multivariate analysis for non-Beijing strains.