Table 2. Hazard Ratios of the Incidence of Deep Venous Thrombosis, Pulmonary Embolism, and Peripheral Artery Disease Associated With Varicose Veins.
| Varicose Veins Group | Control Group | Absolute Risk Difference/1000 Person-Years (95% CI) | Hazard Ratio (95% CI) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| No. of Patients | No. of Cases | No. of Person-Years | Incidence/1000 Person-Years (95% CI)a | No. of Patients | No. of Cases | No. of Person-Years | Incidence/1000 Person-Years (95% CI)a | |||
| DVT | ||||||||||
| Cox model using propensity score–matched controls | 212 984 | 10 360 | 1 581 466 | 6.55 (6.42-6.68) | 212 984 | 1980 | 1 605 243 | 1.23 (1.18-1.29) | 5.32 (5.18-5.46) | 5.30 (5.05-5.56) |
| Multivariable-adjusted modelb | 212 984 | 10 360 | 1 581 466 | 6.55 (6.42-6.68) | 851 936 | 6942 | 6 440 345 | 1.08 (1.05-1.10) | 5.47 (5.34-5.60) | 5.39 (5.22-5.56) |
| DVT (restricted to length of follow-up ≥1 y) | ||||||||||
| Cox model using propensity score–matched controls | 208 648 | 6060 | 1 371 818 | 4.42 (4.31-4.53) | 211 403 | 1545 | 1 393 182 | 1.11 (1.05-1.17) | 3.31 (3.19-3.43) | 3.98 (3.77-4.21) |
| Multivariable-adjusted modelb | 208 648 | 6060 | 1 371 818 | 4.42 (4.31-4.53) | 847 026 | 5488 | 5 591 184 | 0.98 (0.96-1.01) | 3.44 (3.33-3.55) | 3.99 (3.84-4.14) |
| PE | ||||||||||
| Cox model using propensity score–matched controls | 212 984 | 793 | 1 639 174 | 0.48 (0.45-0.52) | 212 984 | 451 | 1 613 354 | 0.28 (0.25-0.31) | 0.20 (0.16-0.24) | 1.73 (1.54-1.94) |
| Multivariable-adjusted modelb | 212 984 | 793 | 1 639 174 | 0.48 (0.45-0.52) | 851 936 | 1521 | 6 469 344 | 0.24 (0.22-0.25) | 0.24 (0.20-0.28) | 1.75 (1.60-1.91) |
| PAD | ||||||||||
| Cox model using propensity score–matched controls | 212 984 | 16 615 | 1 547 861 | 10.73 (10.57-10.90) | 212 984 | 9709 | 1 561 421 | 6.22 (6.09-6.34) | 4.51 (4.31-4.71) | 1.72 (1.68-1.77) |
| Multivariable-adjusted modelb | 212 984 | 16 615 | 1 547 861 | 10.73 (10.57-10.90) | 851 936 | 32725 | 6 296 328 | 5.20 (5.14-5.25) | 5.53 (5.36-5.70) | 1.76 (1.72-1.79) |
Abbreviations: DVT, deep venous thrombosis; PAD, peripheral artery disease; PE, pulmonary embolism.
a
Exact CIs for Possion distribution.
b
The analysis was performed using the sample of age-, sex-, and calendar year–matched controls. Models were adjusted for sex, age, index year, number of outpatient visits during the year before index date, and comorbidities including hypertension, diabetes, chronic obstructive pulmonary disease, hyperlipidemia, malignancy, heart failure, ischemic heart disease, stroke, and chronic renal insufficiency.