Table 2.
Relative risks of fracture between groups by period
| Groups | Period before surgery (or index date) | Period after surgery (or index date) | |||||
|---|---|---|---|---|---|---|---|
| No (%) with fractures | Unadjusted RR (95% CI) | Adjusted RR* (95% CI) | No (%) with fractures | Unadjusted RR (95% CI) | Adjusted RR* (95% CI) | ||
| Bariatric group (n=12 676) | 1326 (10.5) | 1.65 (1.55 to 1.76) | 1.30 (1.21 to 1.39) | 514 (4.1) | 1.85 (1.68 to 2.04) | 1.44 (1.29 to 1.59) | |
| Obese group (n=38 028) | 3065 (8.1) | 1.22 (1.17 to 1.27) | 1.18 (1.13 to 1.23) | 1013 (2.7) | 1.13 (1.04 to 1.21) | 1.04 (0.96 to 1.12) | |
| Non-obese group (n=126 760) | 8329 (6.6) | Reference | Reference | 3008 (2.4) | Reference | Reference | |
| P value† | ---- | <0.001 | <0.001 | ---- | <0.001 | <0.001 | |
RR=relative risk.
*Adjusted for duration of follow-up, material and social deprivation, area of residence, history of fractures (analysis for period after index date only), and number of comorbidities in previous five years, using multivariate conditional Poisson regression model.
†Type III P value for group variable.