Table 2.
Meta-analysis including subgroup analysis of aromatase inhibitors, tamoxifen, and control groups on fractures.
| Treatment arms | Study (n) | Participant (n) | Pooled RR (95% CI) | p for effect | I2 (%)a | p for subgroup differences | ID of article included |
|---|---|---|---|---|---|---|---|
| Tam versus control (no-Tam)b | |||||||
| Total effect | 5 | 37,783 | 0.95 (0.84, 1.07) | 0.39 | 0 | 0 | 2, 3, 35, 36, 37 |
| Subgroup analysis | |||||||
| Menopausal status | 0.65 | ||||||
| Premenopausal | 0 | – | – | – | – | ||
| Pre-/postmenopausal | 4 | 0.95 (0.84, 1.08) | 0.42 | 0 | 3, 35, 36, 37 | ||
| Postmenopausal | 1 | 0.75 (0.27, 2.05) | 0.57 | – | 2 | ||
| Prior tamoxifen treatment | 0.74 | ||||||
| No | 4 | 0.95 (0.84, 1.07) | 0.41 | 0 | 2, 35, 36, 37 | ||
| Yes | 1 | 0.81 (0.32, 2.05) | 0.66 | – | 3 | ||
| Study design | 0.58 | ||||||
| RCT | 2 | 0.78 (0.40, 1.55) | 0.48 | 0 | 2, 3 | ||
| Cohort | 3 | 0.95 (0.84, 1.08) | 0.45 | 0 | 35, 36, 37 | ||
| AIs versus control (no-AIs)b | |||||||
| Total effect | 7 | 59,258 | 1.17 (1.07, 1.28) | <0.01 | 8 | 4, 6, 9, 10, 35, 36, 37 | |
| Subgroup analysis | |||||||
| Menopausal status | 0.88 | ||||||
| Premenopausal | 0 | – | – | – | – | ||
| Pre-/postmenopausal | 4 | 1.19 (1.01, 1.41) | 0.04 | 49 | 4, 35, 36, 37 | ||
| Postmenopausal | 3 | 1.17 (0.97, 1.41) | 0.10 | 0 | 6, 9, 10 | ||
| Prior tamoxifen treatment | 0.99 | ||||||
| No | 5 | 1.18 (1.02, 1.37) | 0.03 | 35 | 4, 9, 35, 36, 37 | ||
| Yes | 2 | 1.18 (0.97, 1.42) | 0.09 | 0 | 6, 10 | ||
| Study design | 0.88 | ||||||
| RCT | 3 | 1.17 (0.97, 1.41) | 0.10 | 0 | 6, 9, 10 | ||
| Cohort | 4 | 1.19 (1.01, 1.41) | 0.04 | 49 | 4, 35, 36, 37 | ||
| AI treatment duration | 0.57 | ||||||
| ⩽48 months | 2 | 1.18 (0.97, 1.42) | 0.09 | 0 | 6, 10 | ||
| 60 months | 1 | 0.81 (0.23, 2.90) | 0.75 | – | 9 | ||
| AI drug | 0.93 | ||||||
| Nonsteroidal (letrozole and anastrozole) | 1 | 1.15 (0.94, 1.41) | 0.16 | – | 6 | ||
| Steroidal (exemestane) | 2 | 1.27 (0.76, 2.14) | 0.36 | 0 | 9, 10 | ||
| Any AI | 4 | 1.19 (1.01, 1.41) | 0.04 | 49 | 35, 36, 37 | ||
| AIs versus Tamb | |||||||
| Total effect | 9 | 20,403 | 1.35 (1.21, 1.51) | <0.01 | 12 | 14, 15, 18, 26, 30, 32, 33, 36, 37 | |
| Subgroup analysis | |||||||
| Menopausal status | 0.75 | ||||||
| Premenopausal | 1 | 1.08 (0.5, 2.35) | 0.85 | – | 14 | ||
| Pre-/postmenopausal | 2 | 2.00 (0.36, 11.21) | 0.43 | 67 | 36, 37 | ||
| Postmenopausal | 6 | 1.39 (1.26, 1.54) | <0.01 | 0 | 15, 18, 26, 30, 32, 33 | ||
| Prior tamoxifen treatment | 0.5 | ||||||
| No | 5 | 1.38 (1.18, 1.62) | <0.01 | 27 | 14, 18, 26, 36, 37 | ||
| Yes | 4 | 1.27 (1.07, 1.51) | <0.01 | 0 | 15, 30, 32, 33 | ||
| Study design | 0.68 | ||||||
| RCT | 7 | 1.39 (1.26, 1.53) | <0.01 | 0 | 14, 15, 18, 26, 30, 32, 33 | ||
| Cohort | 2 | 2.00 (0.36, 11.21) | 0.43 | 67 | 36, 37 | ||
| AI treatment duration | 0.19 | ||||||
| ⩽48 months | 5 | 1.26 (1.07, 1.50) | <0.01 | 0 | 14, 15, 30, 32, 33 | ||
| 60 months | 2 | 1.45 (1.29, 1.64) | <0.01 | 0 | 18, 26 | ||
| AI drug | 0.76 | ||||||
| Nonsteroidal (letrozole and anastrozole) | 6 | 1.41 (1.26, 1.59) | <0.01 | 0 | 14, 15, 18, 26, 32, 33 | ||
| Steroidal (exemestane) | 1 | 1.32 (1.10, 1.58) | <0.01 | – | 30 | ||
| Any AI | 2 | 2.00 (0.36, 11.21) | 0.43 | 67 | 36, 37 | ||
Values in bold indicate statistical significance.
AI, aromatase inhibitor; CI, confidence interval; RCT, randomized controlled trial; RR, risk ratio; Tam, tamoxifen.
a
For heterogeneity.
b
Reference group.