Volume 23, Number 3—March 2017
Research
Pulmonary Nontuberculous Mycobacteria–Associated Deaths, Ontario, Canada, 2001–2013
, Michael A. Campitelli, Hong Lu, Hannah Chung, Sarah K. Brode, Alex Marchand-Austin, Kevin L. Winthrop, Andrea S. Gershon, Jeffrey C. Kwong1, and Frances B. Jamieson1
Table 2
Characteristics of patients with NTM pulmonary isolation and matched persons without NTM for MAC, Mycobacterium xenopi, and M. abscessus, Ontario, Canada, 2001–2013*
| Characteristic |
MAC | M. xenopi | M. abscessus | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Isolation,
n = 5,242 |
Control,
n = 5,242 |
SDM |
Isolation,
n = 2,693 |
Control,
n = 2,693 |
SDM |
Isolation,
n = 162 |
Control,
n = 162 |
SDM |
|||
| Female sex, % | 51 | 51 | 0 | 48 | 47 | 0 | 49 | 49 | 0 | ||
| Median age, y (IQR) |
65 (49–76) |
65 (49–76) |
0 |
65 (48–76) |
65 (48–76) |
0 |
60 (43–74) |
60 (43–74) |
0 |
||
| Underlying condition, % | |||||||||||
| Asthma | 29 | 25 | 0.09 | 31 | 26 | 0.1 | 25 | 20 | 0.12 | ||
| COPD | 36 | 41 | 0.1 | 38 | 42 | 0.09 | 25 | 26 | 0.01 | ||
| Diabetes | 18 | 23 | 0.12 | 19 | 21 | 0.06 | 15 | 16 | 0.03 | ||
| Rheumatoid arthritis | 3 | 2 | 0.06 | 3 | 3 | 0.01 | <4† | 5 | 0.09 | ||
| Chronic kidney disease | 6 | 7 | 0.05 | 7 | 8 | 0.03 | 5 | 6 | 0.05 | ||
| GERD | 14 | 17 | 0.08 | 15 | 17 | 0.05 | 14 | 13 | 0.02 | ||
| Bronchiectasis | 7 | 4 | 0.13 | 6 | 4 | 0.09 | 6 | 5 | 0.03 | ||
| Interstitial lung disease | 3 | 2 | 0.06 | 3 | 3 | 0.03 | <4† | 4 | 0.11 | ||
| Lung cancer | 2 | 2 | 0.02 | 2 | 2 | 0.04 | <4† | <4† | 0.18 | ||
| HIV infection‡ | 1 | 0.2 | 0.13 | 2 | <0.2† | 0.19 | 0 | 0 | |||
| Solid organ transplant‡ | 0.3 | 0.3 | 0 | 0.5 | <0.2† | 0.07 | 0 | <4† | 0.11 | ||
| BMT‡ | 0.1 | 0.1 | 0 | <0.2† | <0.2%† | 0.04 | 0 | 0 | |||
| Cystic fibrosis‡ | 0.4 | 0.1 | 0.05 | 0.2 | 0 | 0.07 | 5 | <4† | 0.27 | ||
| Prior tuberculosis‡ |
3 |
<0.1† |
0.23 |
3 |
<0.2%† |
0.25 |
<4† |
0 |
0.19 |
||
| Hospitalizations§ |
0.31 ± 0.77 |
0.30 ± 0.76 |
0.01 |
0.33 ± 0.78 |
0.31 ± 0.78 |
0.02 |
0.19 ± 0.53 |
0.23 ± 0.60 |
0.09 |
||
| ED visits§ |
0.83 ± 1.22 |
0.79 ± 1.79 |
0.02 |
0.81 ± 1.21 |
0.77 ± 1.59 |
0.03 |
0.49 ± 0.88 |
0.46 ± 1.08 |
0.03 |
||
| ACG diagnoses | 9.0 ± 4.1 | 8.7 ± 4.1 | 0.06 | 9.1 ± 4.2 | 8.8 ± 4.2 | 0.08 | 7.3 ± 4.3 | 7.4 ± 4.4 | 0.01 | ||
*Matched according to age (years), sex, index date (± 90 d), and propensity score (estimating the patient-level likelihood of species-specific NTM pulmonary isolation) value within 0.2 × SD of the exposed patient. NTM pulmonary isolation was defined as the presence of 1 positive sputum specimen. Controls were persons without NTM matched by age, sex, index date, and propensity score. ACG, adjusted clinical group diagnoses using the ACG case mix system (16); BMT, hematopoietic stem cell transplant; COPD, chronic obstructive pulmonary disease; ED, emergency department; GERD, gastresophageal reflux disease; IQR, interquartile range; MAC, Mycobacterium avium complex; NTM, nontuberculous mycobacteria; SDM, standardized difference of the mean (value <0.1 generally considered not significant) (17). Blank cells indicate value undefined.
†Range reported because of small cell size (direct or by inference), which according to privacy regulations cannot be reported.
‡Baseline characteristics not included in the propensity score because of their effect to substantially reduce successful matching of exposed cases with unexposed controls. Inclusion of these variables as covariates was explored, but none significantly altered the hazard ratio point estimates.
§Number of events in year before index date.
1These authors contributed equally to this article.