Table 4.
Unadjusted hazard ratios and 95% confidence intervals for association of community acquired pneumonia with proton pump inhibitors (PPI), before and after prescription, according to three different definitions of community acquired pneumonia (prior event rate ratio adjusted hazard ratio)
| Parameter | Pneumonia definition | |||||||
|---|---|---|---|---|---|---|---|---|
| Broad primary care definition | Narrow primary care definition | Hospital and mortality records based definition (in HES/ONS linked patients) | ||||||
| Unexposed | Exposed | Unexposed | Exposed | Unexposed | Exposed | |||
| No of patients matched for date, sex, and 5 years age band | 160 000 | 160 000 | 160 000 | 160 000 | 128 943 | 128 943 | ||
| Before prescription: | ||||||||
| No (%) pneumonia events | 4298 (2.7) | 9642 (6.0) | 178 (0.1) | 610 (0.4) | 553 (0.4) | 1917 (1.5) | ||
| Incidence of pneumonia per 1000 person years (95% CI) | 27.24 (26.43 to 28.06) | 62.07 (60.85 to 63.32) | 1.11 (0.96 to 1.28) | 3.81 (3.52 to 4.13) | 4.29 (3.95 to 15.67) | 14.94 (14.29 to 15.62) | ||
| Hazard ratio (PPI/non-PPI) (95% CI) | 2.26 (2.18 to 2.35) | 3.42 (2.89 to 4.04) | 3.44 (3.12 to 3.78) | |||||
| After prescription: | ||||||||
| No (%) pneumonia events | 4516 (2.8) | 8727 (5.45) | 297 (0.2) | 724 (0.5) | 779 (0.6) | 1684 (1.3) | ||
| Incidence of pneumonia per 1000 person years (95% CI) | 30.41 (29.54 to 31.31) | 61.41 (60.14 to 62.71) | 1.97 (1.76 to 2.20) | 4.95 (4.60 to 5.33) | 6.52 (6.08 to 7.00) | 14.6 (13.92 to 15.31) | ||
| Hazard ratio (PPI/non-PP) (95% CI) | 2.06 (1.98 to 2.14) | 2.82 (2.44 to 2.36) | 2.55 (2.33 to 2.80) | |||||
| Prior event rate ratio* (95% CI) | 0.91 (0.83 to 0.99) | 0.82 (0.53 to 1.20) | 0.74 (0.69 to 0.97) | |||||
HES=Hospital Episode Statistics; ONS=Office for National Statistics.
*Hazard ratio for pneumonia between exposed and unexposed patients after PPI prescription, divided by hazard ratio for pneumonia before proton pump inhibitor prescription.