Risks of VTE by patient risk category (low, medium, or high) in major abdominal, urologic, and gynecologic surgery, with RRs estimated using Poisson regression
| . | Patient VTE risk category . | ||
|---|---|---|---|
| Low . | Medium . | High . | |
| RR (95% CI); P value | 1.00 (reference) | 1.56 (1.01-2.43); P = .047 | 3.60 (1.90-6.83); P < .001 |
| n/N (%) | 56/8329 (0.7%) | 30/2853 (1.1%) | 11/454 (2.4%) |
| . | Patient VTE risk category . | ||
|---|---|---|---|
| Low . | Medium . | High . | |
| RR (95% CI); P value | 1.00 (reference) | 1.56 (1.01-2.43); P = .047 | 3.60 (1.90-6.83); P < .001 |
| n/N (%) | 56/8329 (0.7%) | 30/2853 (1.1%) | 11/454 (2.4%) |
Low risk was BMI <35 kg/m2, age <75 years, and no history of VTE. Medium risk was BMI ≥35 kg/m2 or age ≥75 years, without a history of VTE. High risk was history of VTE or both BMI ≥35 kg/m2 and age ≥75 years. The table presents both relative risks (RRs) and absolute 30-day event rates of VTE. RRs and 95% CIs were estimated in a Poisson regression model with a robust variance estimator.