Nontuberculous mycobacterial pulmonary disease (NTM-PD) among adults ≥35 years of age, with and without obstructive lung disease in Ontario, Canada, 2001–2013
| NTM-PD | Total Ontario population | No obstructive lung disease | COPD | Asthma |
| Subjects | 6 290 603 | 5 436 773 | 543 119 | 406 712 |
| Primary analysis | ||||
| Cases | 9658 | 4398 | 4538 | 1850 |
| Incidence (95% CI)# | 13.33 (13.07–13.60) | 6.63 (6.44–6.83) | 143.26 (139.12–147.49) | 52.83 (50.45–55.30) |
| Unadjusted HR (95% CI) | Not applicable | 1.00 (ref.) | 20.03 (19.19–20.91) | 8.47 (7.99–8.98) |
| Age- and sex-adjusted HR (95% CI) | Not applicable | 1.00 (ref.) | 12.51 (11.94–13.10) | 7.74 (7.30–8.21) |
| Fully adjusted HR (95% CI)¶ | Not applicable | 1.00 (ref.) | 8.73 (8.29–9.18) | 5.14 (4.83–5.47) |
| Sensitivity analysis | ||||
| Cases | Not applicable | 5350 | 3650 | 1564 |
| Incidence (95% CI)# | Not applicable | 8.01 (7.80–8.23) | 128.54 (124.40–132.77) | 48.12 (45.77–50.57) |
| Unadjusted HR (95% CI) | Not applicable | 1.00 (ref.) | 15.45 (14.79–16.13) | 7.27 (6.84–7.72) |
| Age- and sex-adjusted HR (95% CI) | Not applicable | 1.00 (ref.) | 9.15 (8.73–9.59) | 6.58 (6.19–6.99) |
| Fully adjusted HR (95% CI)¶ | Not applicable | 1.00 (ref.) | 6.01 (5.71–6.33) | 4.26 (3.99–4.55) |
Because some patients with chronic obstructive pulmonary disease (COPD) also had asthma and some patients with asthma also had COPD, these two groups were not mutually exclusive. Primary analysis: NTM-PD was assigned to COPD or asthma if NTM-PD was diagnosed at any time after the diagnosis of COPD or asthma. Sensitivity analysis: NTM-PD was assigned to COPD or asthma if NTM-PD diagnosed ≥1 year after the diagnosis of COPD or asthma. Asthma was defined as fulfilling the diagnostic definition of asthma, regardless of co-existing COPD. COPD was defined as fulfilling the diagnostic definition of COPD, regardless of co-existing asthma. Hazard ratios (HRs) were calculated by Cox proportional hazards regression. #: calculated per 100 000 person-years with Poisson 95% confidence intervals; ¶: controlling for age, sex, income, rurality and comorbidities that may be associated with NTM-PD (bronchiectasis, chronic kidney disease, diabetes mellitus, gastro-oesophageal reflux disease, HIV infection, lung cancer, rheumatoid arthritis, transplantation (haematopoietic stem cell or solid organ) and prior culture-proven tuberculosis) modelled in a time-varying fashion.