Use of proton pump inhibitors (PPIs) and risk of community-acquired pneumonia (CAP)
| Exposure | CAP events n | Incidence rate per 1000 person-years | Age/sex-adjusted HR (95% CI) | Fully adjusted HR# (95% CI) |
| Never PPI or H2RA | 21 471 | 19.1 | Reference | Reference |
| PPI use by time since last prescription | ||||
| Current: 1–30 days | 739 | 68.4 | 2.66 (2.47–2.86) | 2.05 (1.90–2.22) |
| Recent: 31–60 days | 288 | 45.2 | 2.13 (1.89–2.39) | 1.72 (1.53–1.94) |
| Past: 61–210 days | 729 | 36.9 | 2.12 (1.97–2.28) | 1.79 (1.66–1.93) |
| Distant past: ≥211 days | 1588 | 19.8 | 1.39 (1.32–1.46) | 1.29 (1.23–1.36) |
| Current PPI use by duration of use | ||||
| 1–30 days | 186 | 41.8 | 2.29 (1.99–2.65) | 1.89 (1.63–2.18) |
| 31–60 days | 75 | 80.1 | 2.22 (1.77–2.79) | 1.81 (1.44–2.27) |
| 61–210 days | 241 | 95.1 | 2.62 (2.30–2.97) | 2.04 (1.79–2.32) |
| ≥211 days | 237 | 82.0 | 3.32 (2.92–3.77) | 2.34 (2.06–2.67) |
| Current use of both PPI and H2RA | 73 | 111.1 | 3.47 (2.76–4.36) | 2.52 (2.00–3.18) |
H2RA: histamine-2 receptor antagonist; HR: hazard ratio. #: adjusted for age, sex, history of pneumonia, gastro-oesophageal reflux 1 year before, asthma, bronchopulmonary dysplasia and cystic fibrosis. All analyses are adjusted for use of H2RAs.