Table 4.
Odds ratios (ORs), with 95% confidence intervals (CIs), for femoral stress fractures associated with bisphosphonate use
| Bisphosphonate use | Cases Controls | Age- and sex-adjusted OR (CI) | Multi variable-adjusted a OR (CI) | |
|---|---|---|---|---|
| Never use | 38 | 842 | 1.0 (reference) | 1.0 (rreference) |
| Ever use | 134 | 110 | 26 (20–34) | 26 (18–38) |
| (78%) | (12%) | |||
| Alendronate use | 120 | 73 | 36 (29–44) | 36 (28–46) |
| Any other oral bisphosphonate | 18 | 39 | 7.8 (4.1–15) | 8.0 (4.0–16) |
| Risedronate use | 16 | 26 | 12 (6.5–21) | 13 (6.1–26) |
| Etidronate use | 0 | 13 | NA | NA |
| Ibandronate use | 2 | 0 | NA | NA |
| Zoledronate use | 0 | 2 | NA | NA |
| Per year since last use | 0.31 (0.28–0.36) | 0.31 (0.27–0.35) | ||
| Per year of use | 2.6 (2.1–3.2) | 2.5 (2.0–3.1) | ||
| Current use (within the last year) | 129 | 79 | 34 (26–46) | 35 (23–51) |
| Years of use b in current users | ||||
| 0–1 | 1 | 10 | 1.3 (0.1–16) | 1.7 (0.2–19) |
| 1–2 | 5 | 11 | 8.4 (2.5–28) | 8.2 (2.5–27) |
| 2–3 | 17 | 11 | 27 (25–30) | 29 (26–32) |
| 3–4 | 12 | 5 | 47 (22–99) | 40 (17–91) |
| 4–5 | 13 | 3 | 81 (40–164) | 116 (58–234) |
| > 5 | 11 | 5 | 85 (66–111) | 93 (66–132) |
| Women | ||||
| Never use | 30 | 670 | 1.0 (reference) | 1.0 (reference) |
| Ever use | 130 | 104 | 26 (21–33) | 29 (21–41) |
| (81%) | (13%) | |||
| Per year of use | 2.6 (2.2–3.2) | 2.6 (2.1–3.3) | ||
| Per year since last use | 0.30 (0.28–0.33) | 0.29 (0.26–0.32) | ||
| Men | ||||
| Never use | 8 | 172 | 1.0 (reference) | 1.0 (reference) |
| Ever use | 4 | 6 | 19.1 (8.0–46.0) | 19.0 (9.9–36.6) |
| (33%) | (3%) | |||
| Per year of use | 2.1 (1.3–3.3) | 2.4 (2.1–2.7) | ||
| Per year since last use | 0.37 (0.28–0.50) | 0.37 (0.30–0.47) |
a
Adjusted by age (continuous), sex, cortisone use (yes/no), and Charlson’s co-morbidity index (continuous).
b
First use after October 1, 2005 to ascertain non-use in the period July through September 2005. The national Swedish Prescription Register started on July 1, 2005, and provides complete national data on individuals exposed to dispensed drugs in the Swedish population; the drugs are normally dispensed every third month.
NA: not applicable.