Deep vein thrombosis in severe community-acquired pneumonia patients undergoing thromboprophylaxis: Prevalence, risk factors, and outcome.

Background: Even with adherence to thromboprophylaxis recommended by guidelines, the incidence of deep vein thrombosis (DVT) remains high among patients with severe community-acquired pneumonia (SCAP). There is an urgent need to identify the risk factors for DVT in these patients to optimize preventive strategies.

Study design and methods: We retrospectively enrolled 309 adults with SCAP admitted to Beijing Chao-Yang Hospital between 1 January 2015 and 30 June 2023. All patients received guideline-recommended thromboprophylaxis and lower extremity venous compression ultrasound scanning. Clinical characteristics, including demographic information, clinical history, vital signs, laboratory findings, treatments, complications, and outcomes, were analyzed for patients with and without DVT in these two cohorts.

Results: Of the 309 patients, 110 (35.6%) developed 1ower extremity DVT. There was no significant difference in the incidence of DVT among the different prophylactic measures (P = 0.393). Multivariate logistic regression analysis showed an association between a history of VTE (OR, 13.388, 95% CI: 2.179 ~ 82.257; P = 0.005), bedridden time > 3 days (OR, 17.672, 95% CI: 5.686 ~ 54.929; P < 0.001), D-dimer levels ≥ 1.0 µg/mL (OR, 2.109, 95% CI: 1.018 ~ 4.372; P = 0.045), LDH levels ≥ 400 U/L (OR, 2.548, 95% CI: 1.308 ~ 4.965; P = 0.006), IMV (OR, 2.479, 95% CI: 1.233 ~ 4.986; P = 0.011) and the occurrence of DVT. A new prediction model, including history of VTE, bedridden time, D-dimer levels, LDH levels and IMV, showed a better performance in predicting DVT (AUC = 0.856; 95% CI: 0.766 ~ 0.921; sensitivity: 80.6%; specificity: 81.4%) than Padua prediction score (AUC = 0.666) and Caprini prediction score (AUC = 0.688) for patients with SCAP. The 30-day mortality and in-hospital mortality in the DVT group were significantly higher than those in the non-DVT group.

Conclusions: Even received guideline-recommended thromboprophylaxis, the prevalence of DVT among patients with SCAP remains unexpectedly high which is also associated with a poor prognosis. It is necessary to identify people at high risk of DVT early and refine the preventive strategies accordingly to improve patient outcomes.