COVID-19 may exacerbate risk of deep vein thrombosis

Deep vein thrombosis (DVT) appears to be common in patients with the coronavirus disease 2019 (COVID-19) and is associated with worse outcomes, a new study has found.

“[W]e performed a single institutional study of the patients with confirmed COVID-19 pneumonia and found from ultrasound scans a high prevalence of DVT and an association between DVT and CURB-65* scores, Padua scores, and D-dimer levels in hospitalized patients with COVID-19,” researchers said.

Among the 143 patients (mean age, 63±14 years; 51.7 percent male) included, frequently presenting symptoms for COVID-19 were fever, dry coughs, fatigue, headache, diarrhoea, and dyspnoea. Comorbidities such as hypertension, diabetes mellitus, and coronary artery disease were also common. One patient had a history of venous thromboembolism. [Circulation 2020;142:114-128]

Almost half (n=66; 46.1 percent) were found to have DVT, of whom 23 had proximal DVT, and the remaining 43 had distal DVT.

Multivariate logistic regression analysis revealed that a higher Padua score was a significant predictor of DVT risk in COVID-19 patients (odds ratio [OR] for score ≥4, 4.016, 95 percent confidence interval [CI], 1.069–15.094; p=0.04). The same was true for an elevated CURB-65 score (OR for scores 3–5, 6.122, 95 percent CI, 1.190–31.773; p=0.031) and D-dimer levels (OR for D-dimer >1.0 µg/mL, 5.818, 95 percent CI, 1.422–23.809; p=0.014).

Taking all three risk factors together gave high predictive accuracy for DVT (area under the curve, 0.817, 95 percent CI, 0.739–0.879). The sensitivity and specificity values were 88.52 percent and 61.43 percent, respectively.

DVT patients also saw worse outcomes. They were commonly sent to the intensive care (12 vs 3 admissions; p=0.005) and were less frequently discharged (32 vs 60; p<0.001). Death was also more common in the DVT subgroup (23 vs 9; p=0.001). Kaplan-Meier survival curves additionally revealed a greater rate of adverse clinical outcomes in COVID-19 patients with DVT (p=0.004). This remained true in both proximal and distal DVT subgroups.

“In hospitalized patients with COVID-19, the prevalence of DVT is high and is associated with adverse outcomes,” the researchers said. “Because the prevalence of DVT is higher in this cohort than in other severe or critical respiratory or high-risk groups, we suspect that COVID-19 is an additional risk factor for DVT in the hospitalized patients.”

“Prevention of DVT with low-molecular-weight heparin in high risk patients may reduce DVT in hospitalized patients with COVID-19,” they added.

Important study limitations include the lack of a non-COVID-19 control group, which otherwise could have more strongly validated the higher prevalence of DVT in COVID-19 patients, as well as the associated adverse outcomes.

*Confusion status, urea, respiratory rate, and blood pressure