Table 5.
Risk of hip fracture according to use of proton pump inhibitors (PPI) in selected strata of 79 899 postmenopausal women enrolled in the Nurses’ Health Study
| Stratum | Non-user of PPIs | Regular PPI user | Pinteraction* |
|---|---|---|---|
| Age | |||
| ≤65 years: | 1.00 | ||
| No of cases/No of person years | 66/160 861 | 12/21 360 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.51 (0.80 to 2.86) | |
| Multivariable adjusted† | 1.00 | 1.34 (0.70 to 2.60) | |
| >65 years: | |||
| No of cases/No of person years | 678/331 294 | 137/52 273 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.34 (1.10 to 1.61) | |
| Multivariable adjusted† | 1.00 | 1.36 (1.12 to 1.64) | |
| Body mass index | |||
| <25: | 0.54 | ||
| No of cases/No of person years | 455/218 797 | 85/25 372 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.54 (1.21 to 1.95) | |
| Multivariable adjusted† | 1.00 | 1.45 (1.14 to 1.85) | |
| ≥25: | |||
| No of cases/No of person years | 289/273 357 | 64/48 260 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.30 (0.99 to 1.72) | |
| Multivariable adjusted† | 1.00 | 1.23 (0.93 to 1.64) | |
| Postmenopausal hormone use | |||
| Never or previously used: | 0.72 | ||
| No of cases/No of person years | 625/350 735 | 125/54 534 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.36 (1.11 to 1.66) | |
| Multivariable adjusted† | 1.00 | 1.36 (1.11 to 1.66) | |
| Currently used: | |||
| No of cases/No of person years | 119/141 419 | 24/19 099 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.44 (0.91 to 2.28) | |
| Multivariable adjusted† | 1.00 | 1.36 (0.84 to 2.19) | |
| Smoking status | |||
| Never: | 0.03 | ||
| No of cases/No of person years | 322/220 553 | 49/31 829 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.07 (0.78 to 1.45) | |
| Multivariable adjusted† | 1.00 | 1.06 (0.77 to 1.46) | |
| Current or past: | |||
| No of cases/No of person years | 422/271 600 | 100/41 803 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.54 (1.23 to 1.93) | |
| Multivariable adjusted† | 1.00 | 1.51 (1.20 to 1.91) | |
| Corticosteroid use | |||
| User: | 0.10 | ||
| No of cases/No of person years | 71/29 054 | 40/9816 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.87 (1.22 to 2.86) | |
| Multivariable adjusted† | 1.00 | 2.09 (1.32 to 3.30) | |
| Non-user: | |||
| No of cases/No of person years | 673/463 101 | 109/63 817 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.19 (0.97 to 1.47) | |
| Multivariable adjusted† | 1.00 | 1.26 (1.02 to 1.55) | |
| History of osteoporosis | |||
| Yes: | 0.76 | ||
| No of cases/No of person years | 392/353 613 | 62/45 687 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.25 (0.98 to 1.60) | |
| Multivariable adjusted† | 1.00 | 1.28 (1.00 to 1.64) | |
| None: | |||
| No of cases/No of person years | 352/138 542 | 87/27 945 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.31 (1.00 to 1.73) | |
| Multivariable adjusted† | 1.00 | 1.41 (1.07 to 1.87) | |
| Calcium intake | |||
| ≥900 mg/day: | 0.38 | ||
| No of cases/No of person years | 371/274 346 | 79/42 070 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.41 (1.10 to 1.82) | |
| Multivariable adjusted† | 1.00 | 1.42 (1.10 to 1.83) | |
| <900 mg/day: | |||
| No of cases/No of person years | 373/217 810 | 70/31 563 | |
| Hazard ratio (95% CI): | |||
| Age adjusted | 1.00 | 1.26 (0.97 to 1.64) | |
| Multivariable adjusted† | 1.00 | 1.25 (0.95 to 1.64) | |
*We evaluated effect modification using cross classified categories of hip fracture risk factors and PPI use. We tested significance of interactions using the log-likelihood ratio test comparing the model with cross classified categories with a model that included the risk factors as independent variables.
†Adjusted for same variables as Table 3 minus the stratum covariate.