Prevalence of lower limb deep vein thrombosis and associated factors among Breast Cancer patients on chemotherapy at Uganda cancer institute

Abstract

Background Cancer and its treatments are well recognized risk factors for venous thromboembolism. Evidence suggests that VTE risk depends on; stage of cancer, age of patient, type of chemotherapy, surgery, immobilization and other comorbid features. The most common malignancies associated with thrombosis are breast, colon and lung cancers reflecting the prevalence of these malignancies in the general population. However, when adjusted for disease prevalence, pancreatic, ovarian and brain cancers are strongly associated with thrombotic complications. Deep vein thrombosis accounts for about two thirds of all venous thrombotic events. DVT leads to pulmonary embolism in 50% of the cases when left untreated which is usually very fatal and one of the causes of sudden death in patients with venous thromboembolism. Breast cancer is among the most prevalent cancer in the world and hence accounts for a significant proportion of VTE events. To prevent complications of venous thromboembolism, we needed to study the deep vein thrombosis trends so that prophylaxis or preventive measures can be considered. Objective The study aimed to determine the prevalence of lower limb deep vein thrombosis and its associated factors among breast cancer patients undergoing chemotherapy at Uganda cancer institute. Methodology This was a descriptive cross-sectional study done at Uganda Cancer Institute, Kampala-Uganda from November 2018 to April 2019. Consecutive sampling method was used, eligible participants were identified, consented, and a clinical assessment done. Doppler ultrasound scanning of the lower limbs was performed to detect evidence of DVT. Results A total of 98 breast cancer patients were recruited and 96.9% were females. The average age of participants was 48 years. Half of the participants were unemployed and less than half had comorbidities with 26.5% hypertensive, while 10.2% diabetic. The prevalence of DVT was found to be 6% with majority of the thrombi in the distal veins of the legs at 71.4%. Among the associated factors, lower limb edema, age of more than 60 years, and diabetes were found to be significant at bivariate analysis. At multivariate analysis, the odds of occurrence of DVT in those with lower limb edema was 20 times as high in those without lower limb edema [(p<0.001), 95% CI 2.17,186.62]. Conclusion Deep vein thrombosis was found to be a major concern among breast cancer patients on chemotherapy and it was strongly associated with lower limb edema, thus clinicians should xii

consider anticoagulation therapy in all breast cancer patients with lower limb edema or perform routine Doppler ultrasound scan monitoring in breast cancer patients on chemotherapy.