Table 3.
Association Between Body Mass Index and Venous Thromboembolism
| Person-Years | Outcomes | IR per 1000 PY (95% CI) | Crude HR (95% CI) | Adjusted* HR (95% CI) | |
|---|---|---|---|---|---|
| VTE overall† | |||||
| Normal weight | 187,052 | 187 | 1.00 (0.87–1.15) | 1 (reference) | 1 (reference) |
| Underweight | 6773 | 6 | 0.89 (0.40–1.97) | 0.95 (0.43–2.13) | 0.96 (0.42–2.15) |
| Overweight | 132,725 | 213 | 1.60 (1.40–1.84) | 1.64 (1.35–1.99) | 1.34 (1.09–1.64) |
| Obesity | 51,104 | 97 | 1.90 (1.56–2.32) | 1.94 (1.52–2.47) | 1.62 (1.26–2.09) |
| VTE provoked | |||||
| Normal weight | 187,052 | 91 | 0.49 (0.40–0.60) | 1 (reference) | 1 (reference) |
| Underweight | 6773 | 5 | 0.74 (0.31–1.78) | 1.56 (0.64–3.82) | 1.41 (0.57–3.50) |
| Overweight | 132,725 | 103 | 0.78 (0.64–0.94) | 1.63 (1.23–2.17) | 1.34 (1.00–1.78) |
| Obesity | 51,104 | 43 | 0.84 (0.62–1.13) | 1.76 (1.23–2.53) | 1.43 (0.98–2.08) |
| VTE unprovoked | |||||
| Normal weight | 187,052 | 96 | 0.51 (0.42–0.63) | 1 (reference) | 1 (reference) |
| Underweight | 6773 | 1 | 0.15 (0.02–1.05) | 0.35 (0.05–2.46) | 0.39 (0.56–2.73) |
| Overweight | 132,725 | 110 | 0.83 (0.69–1.00) | 1.64 (1.25–2.15) | 1.34 (1.01–1.77) |
| Obesity | 51,104 | 54 | 1.06 (0.81–1.38) | 2.11 (1.50–2.95) | 1.81 (1.27–2.58) |
Notes: *Adjusted for the following sets of covariates: age, sex, smoking status, physical activity, level of education, hypertension, atrial fibrillation/flutter, Charlson Comorbidity Index score, statins, vitamin K antagonists, low-dose aspirin. †31 VTE events occurred among individuals with missing information on body mass index, and are therefore not shown.