Muscular Calf Vein Thrombosis Is Associated With Increased 30-Day Mortality But Not 90-Day Mortality in Older Patients With Hip Fracture

Calf deep vein thrombosis (DVT) is common in patients with hip fractures. However, studies on whether calf DVT has an impact on the prognosis are limited. This retrospective cohort study explored the association between calf DVT and 30-day and 90-day all-cause mortality in older patients with hip fractures. A total of 564 consecutive patients who underwent ultrasound examination were identified from our hip fracture database and categorized into patients with calf DVT (axial DVT, muscular DVT) and no DVT. Of these, 86 patients (15.2%) had ultrasound-confirmed calf DVT, including 66 patients with muscular DVT, and 20 patients with axial DVT. The 30-day and 90-day all-cause mortality were 2.5% and 6.0%, respectively. Multivariate Cox analysis showed that calf DVT was significantly associated with an increased risk of 30-day mortality (hazard ratio [HR] 3.21, 95% confidence interval [CI] 1.05 to 9.84, p = 0.04), but this risk relationship did not persist at 90-day follow-up (HR 1.59, 95% CI 0.69 to 3.71, p = 0.28). When calf DVT was further categorized, muscular DVT remained an independent risk factor for 30-day mortality (HR 3.95, 95% CI 1.18 to 13.15, p = 0.03), whereas this relationship was not found in axial DVT (HR 1.79, 95% CI 0.21 to 15.02, p = 0.59). In conclusion, calf DVT, especially muscular calf DVT but not axial DVT, is independently associated with an increased risk of 30-day mortality in older patients with hip fracture, but this risk relationship did not persist at 90-day follow-up.