Prevalence, sonographic findings and factors associated with deep venous thrombosis among HIV in-patients at selected national referral hospitals, Uganda

Abstract

BACKGROUND: Deep vein thrombosis (DVT) is part of a spectrum of venous thromboembolism (VTE) which also includes pulmonary embolism (PE). Up to 50% of hospitalized individuals who develop PE have DVT and PE is said to be responsible for up to 10% of hospital deaths. The burden of DVT among HIV in-patients is not well established in our setting. There exists a paucity of studies that report the specific risk factors for DVT among HIV-positive in-patients. The risk of DVT can be reduced through the use of prophylactic anticoagulation. However, not every hospitalized patient receives prophylactic anticoagulation. Understanding the burden and risk factors for DVT will help determine the need for preventive measures and also help to identify those who need this intervention and inform local guidelines for strategic and cost-effective initiation of thromboprophylaxis. This study aims to determine the prevalence, sonographic findings, and factors associated with lower extremity DVT among HIV in-patients. METHODS: This was a cross-sectional study carried out between October 2023 and April 2024 in two national referral hospitals among adult hospitalized HIV medical in-patients. A total of 186 participants were consecutively sampled and enrolled in the study. All adult HIV-positive in-patients who fulfilled the eligibility criteria had a bedside screening Doppler ultrasound scan of the lower extremity deep veins for DVT. Relevant demographic, clinical, laboratory, and HIV-related data were obtained. Both bivariate and multivariate analyses were done using R software. RESULTS: A total of 186 participants were enrolled with a median age 40 years and an interquartile range (IQR) of (34-52) years. The prevalence of lower extremity DVT was found to be 18.3% (34/186). Participants with DVT had a median age of 49 years and an IQR of (39 – 56) years with a P-value of 0.045. Up to 53% (99/186) of the participants were male. The median duration of hospitalization (IQR) was 5.0 days (IQR: 4.0-7.8) among those with DVT. Up to 74% (25/34) had acute DVT and 47% (16/34) had bilateral lower extremity involvement. A positive history of cigarette smoking was identified in 12/34 participants (6.5%) and was significantly associated with the development of DVT (P-value = 0.004). Up to 74% (138/186) of the participants had at least one comorbidity and 42% (78/186) had Tuberculosis (TB) co-infection. TB was significantly associated with DVT with a prevalence ratio of 2.22(95%Confidence interval (CI): 1.25-3.97) and a P-value of 0.007. A low CD4 count (<200 cells/μ) was also significantly 9

associated with lower extremity DVT, with a prevalence ratio of 2.70 with a 95% CI of (1.41-5.14) and, a P-value of 0.003. CONCLUSION: The prevalence of lower extremity DVT among HIV in-patients is high (18.3%) in our setting. Older age, a positive history of smoking, low CD4 count (<200), and TB co-infection are risk factors for DVT among HIV in-patients. RECOMMENDATION: We recommend lower extremity DVT screening among HIV in-patients particularly those with CD4<200, TB co-infection, and a positive history of smoking. We further recommend larger studies to help develop guidelines for thromboprophylaxis in hospitalized HIV patients.