Prevalence, Risk Factors And Management Of Venous Thromboembolism Amongst Patients Undergoing Breast Cancer Treatment At Kenyatta National Hospital

Abstract

Breast cancer is the second most common malignancy and cause of cancer-related mortality. Cancer has long been associated as a risk factor for hyper-coagulation. It may, therefore, lead to venous thromboembolism in breast cancer patients. Venous thromboembolism is a major risk factor, accounting for the second most common cause of cancer-associated mortality. This has made the management of coagulation in cancer to be both complex and also important. Objective The purpose of this study was to establish the prevalence, risk factors, and management of venous thromboembolism amongst patients undergoing breast cancer treatment at Kenyatta National Hospital. Research Methods The study adopted a cross-sectional study design and was conducted at the Kenyatta National Hospital-oncology department. Three hundred and seventy seven patient’s files which fitted the inclusion criteria were sampled by using simple random sampling technique. Data on the patient’s sociodemographic characteristics, tumor and chemotherapy-related factors were collected by using a predesigned data collection tool. The data was then checked for completeness and data quality. It was then organized, coded and analyzed using STATA version 13. Univariate analysis was done by use of descriptive statistics using mean, median and standard deviation. The risk of developing a venous thromboembolism was assessed by using the Khorana risk assessment tool. Additionally, the strength of association between the predictor and outcome variable was assessed by the use of inferential statistics with a p- value of less than 0.05 considered to be statistically significant. Results The number of patients who were found to have venous thromboembolism was 10 (2.65%). Age was found to be a significant risk factor for the development of venous thromboembolism (p= <0.001). (AOR=0.47; CI=0.24-0.94; p=0.032). Surgery done in the last one year was also found to be a predictor of the risk of having a venous thromboembolic event. (AOR= 0.68; xviii CI=0.48-0.98; p=0.04). The duration it took to initiation of chemotherapy since diagnosis and the number of chemotherapy cycles were also found to be significant predictors of risk of developing a venous thromboembolic event at (p=0.012) and (p=<0.001) respectively. (AOR= 1.64; CI=1.1-2.44; p= 0.015). Additionally, there was a statistically significant association between the use of radiotherapy and the risk of developing a venous thromboembolism (p=<0.001). (AOR=0.09; CI=0.03-0.24; p=0.001). Warfarin and Low molecular weight heparin were commonly used for the management of venous thromboembolism as depicted by 8(80%) of the patients who were managed by using these two agents. Conclusion There is a high prevalence of venous thromboembolism amongst breast cancer patients. Several predictors of the risk of the development of venous thromboembolism were identified in the study. This included the number of chemotherapy cycles, age of the breast cancer patient, use of radiotherapy and surgery in management, and the number of months since breast cancer was first diagnosed. All these risk factors need early detection to enable them to be adequately managed. Recommendation The use of venous thromboembolism risk models should be further explored and used to educate patients who are on a higher risk about the warning signs and symptoms of venous thromboembolism. In addition, modifiable risk factors for the development of a venous thromboembolism should be identified early adequately managed.