HRs (95% CI) for redemption of index PPI prescription and for long-term use of PPI (defined as ≥180 DDD/year)
| Variable | N | N index PPI prescription | HR index PPI prescription | N long-term PPI use | HR long-term PPI use |
|---|---|---|---|---|---|
| Gender | |||||
| Female | 1473 | 1094 | 1.00 (ref) | 688 | 1.00 (ref) |
| Male | 1992 | 1205 | 0.69 (0.63 to 0.75) | 647 | 0.65 (0.58 to 0.72) |
| Age at operation (years) | |||||
| ≤40 | 1100 | 666 | 1.00 (ref) | 323 | 1.00 (ref) |
| 41–50 | 889 | 599 | 1.08 (0.96 to 1.21) | 336 | 1.19 (1.02 to 1.39) |
| 51–60 | 886 | 627 | 1.16 (1.03 to 1.29) | 397 | 1.39 (1.20 to 1.62) |
| 61–70 | 445 | 318 | 1.26 (1.10 to 1.45) | 213 | 1.58 (1.32 to 1.90) |
| 71–80 | 133 | 81 | 1.37 (1.08 to 1.74) | 58 | 1.92 (1.44 to 2.57) |
| ≥81 | 12 | 8 | 2.14 (1.06 to 4.35) | 8 | 4.76 (2.32 to 9.76) |
| Year of index ARS | |||||
| 1996–2000 | 1166 | 819 | 1.00 (ref) | 460 | 1.00 (ref) |
| 2001–2005 | 1324 | 902 | 1.28 (1.16 to 1.41) | 523 | 1.59 (1.38 to 1.82) |
| 2006–2010 | 975 | 578 | 1.65 (1.47 to 1.85) | 352 | 2.25 (1.91 to 2.64) |
| Prior use of PPI | |||||
| 0 DDD | 441 | 255 | 0.63 (0.55 to 0.72) | 125 | 0.50 (0.41 to 0.60) |
| 1–89 DDD | 493 | 282 | 0.63 (0.55 to 0.71) | 129 | 0.50 (0.41 to 0.60) |
| 90–179 DDD | 464 | 286 | 0.74 (0.65 to 0.84) | 132 | 0.55 (0.46 to 0.66) |
| ≥180 DDD | 2067 | 1476 | 1.00 (ref) | 949 | 1.00 (ref) |
| Use of drugs | |||||
| NSAID | 1.96 (1.74 to 2.20) | 1.81 (1.55 to 2.11) | |||
| ASA | 1.24 (1.05 to 1.46) | 1.55 (1.30 to 1.86) | |||
| Clopidogrel | 3.18 (2.05 to 4.91) | 1.83 (1.13 to 2.95) | |||
Age is categorised in intervals of 10 years, and year of index ARS is categorised in intervals of 5 years. Prior use of PPI, expressed in DDD in the year before index surgery, is categorised in four intervals. Use of NSAID, clopidogrel and acetylsalicylic acid (ASA) are time-dependent variables.
ARS, antireflux surgery; DDD, defined daily dose; NSAID, nonsteroidal anti-inflammatory drugs; PPI, proton pump inhibitor.