Table 4.
Nested case-control analysis of exposure to drug treatment and comorbid conditions as predictor of hip fractures in treatment naive adults initially starting alendronate in Denmark. Table summarises several multivariate conditional logistic regression analyses examining exposure in terms of current user status, adherence, or number of dose years
| No (%) of patients | OR (95% CI) for hip fracture | ||
|---|---|---|---|
| Unadjusted | Adjusted* | ||
| Alendronate (users switching to other osteoporosis drugs considered no longer exposed) | |||
| User status: | |||
| Past user (≥1 year before) | 6297 (23.6) | Reference | — |
| Recent user (<1 year before) | 11 592 (43.4) | 0.78 (0.73 to 0.84), P<0.001 | 0.79 (0.74 to 0.86), P<0.001 |
| Current user | 8847 (33.1) | 0.70 (0.65 to 0.76), P<0.001 | 0.70 (0.65 to 0.77), P<0.001 |
| Medication possession ratio: | |||
| <50% | 7125 (26.6) | Reference | — |
| 50-80% | 2838 (10.6) | 0.99 (0.90 to 1.09), P=0.85 | 0.98 (0.89 to 1.08), P=0.65 |
| >80% | 16 773 (62.7) | 0.72 (0.68 to 0.77), P<0.001 | 0.73 (0.69 to 0.79), P<0.001 |
| Dose years: | |||
| <5 | 22 220 (83.1) | Reference | — |
| ≥5-<10 | 4091 (15.3) | 0.74 (0.67 to 0.82), P<0.001 | 0.74 (0.67 to 0.83), P<0.001 |
| ≥10 | 425 (1.6) | 0.74 (0.56 to 0.97), P=0.03 | 0.74 (0.55 to 0.97), P=0.03 |
| Sensitivity analysis: | |||
| Dose years: | |||
| <3 | 18 396 (68.8) | 1.27 (1.15 to 1.40), P<0.001 | 1.24 (1.13 to 1.38), P<0.001 |
| ≥3-<5 | 3767 (14.1) | Reference | — |
| ≥5-<10 | 4091 (15.3) | 0.87 (0.77 to 0.99), P=0.03 | 0.87 (0.77 to 0.99), P=0.04 |
| ≥10 | 425 (1.6) | 0.88 (0.67 to 1.17), P=0.39 | 0.86 (0.65 to 1.15), P=0.32 |
| Alendronate (users switching to other osteoporosis drugs removed from analysis) | |||
| User status: | |||
| Past user (≥1 year before) | 4238 (17.8) | Reference | — |
| Recent user (<1 year before) | 10 907 (45.8) | 0.74 (0.67 to 0.80), P<0.001 | 0.74 (0.68 to 0.81), P<0.001 |
| Current user | 8661 (36.4) | 0.66 (0.60 to 0.72), P<0.001 | 0.65 (0.59 to 0.72), P<0.001 |
| Medication possession ratio: | |||
| <50% | 5020 (21.1) | Reference | — |
| 50-80% | 2372 (10.0) | 0.97 (0.87 to 1.09), P=0.64 | 0.96 (0.85 to 1.08), P=0.47 |
| >80% | 16 414 (68.9) | 0.69 (0.64 to 0.74), P<0.001 | 0.70 (0.64 to 0.75), P<0.001 |
| Dose years: | |||
| <5 | 19 619 (82.4) | Reference | — |
| ≥5-<10 | 3793 (15.9) | 0.68 (0.60 to 0.77), P<0.001 | 0.69 (0.61 to 0.78), P<0.001 |
| ≥10 | 394 (1.7) | 0.64 (0.46 to 0.89), P=0.01 | 0.63 (0.45 to 0.88), P=0.007 |
| Sensitivity analysis: | |||
| Dose years: | |||
| <3 | 16 168 (67.9) | 1.30 (1.15 to 1.45), P<0.001 | 1.26 (1.12 to 1.42), P<0.001 |
| ≥3-<5 | 3451 (14.5) | Reference | — |
| ≥5-<10 | 3793 (15.9) | 0.80 (0.70 to 0.93), P=0.002 | 0.80 (0.69 to 0.92), P=0.002 |
| ≥10 | 394 (1.7) | 0.81 (0.58 to 1.13), P=0.22 | 0.75 (0.53 to 1.06), P=0.10 |
| Comorbid conditions and comedications | |||
| Major osteoporotic fracture | 11 487 (43) | 2.01 (1.89 to 2.13), P<0.001 | 1.99 (1.88 to 2.11), P<0.001 |
| Fracture of pelvis femur or lower leg | 3807 (14.2) | 1.55 (1.44 to 1.66), P<0.001 | 1.37 (1.27 to 1.48), P<0.001 |
| Fractures other | 1050 (3.9) | 1.68 (1.48 to 1.92), P<0.001 | 1.41 (1.24 to 1.62), P<0.001 |
| Diabetes | 1700 (6.4) | 1.22 (1.09 to 1.36), P<0.001 | 1.17 (1.05 to 1.31), P<0.001 |
| Chronic kidney disease | 373 (1.4) | 1.49 (1.19 to 1.85), P<0.001 | 1.35 (1.08 to 1.69), P<0.001 |
| Chronic pulmonary disease | 5498 (20.6) | 1.13 (1.06 to 1.21), P<0.001 | 1.13 (1.05 to 1.21), P<0.001 |
| Previous myocardial infarction | 2374 (8.9) | 1.11 (1.01 to 1.22), P=0.03 | 1.04 (0.95 to 1.15), P=0.39 |
| Prednisolone in past year | 5401 (20.2) | 0.87 (0.81 to 0.93), P<0.001 | 0.87 (0.81 to 0.94), P<0.001 |
| Proton pump inhibitors in past year | 7714 (28.9) | 1.29 (1.22 to 1.37), P<0.001 | 1.25 (1.18 to 1.33), P<0.001 |
| Thiazides in past year | 6949 (26.0) | 0.99 (0.94 to 1.07), P=0.98 | 1.00 (0.94 to 1.07), P=0.94 |
*Adjusted for comorbid diabetes, chronic kidney disease, chronic pulmonary disease, and previous myocardial infarction, and use in past year of prednisolone, proton pump inhibitors, and thiazides.