CARDIOVASCULAR JOURNAL OF AFRICA • Volume 33, No 4, July/August 2022 AFRICA 191 In an observational study from France comparing rivaroxaban and VKA for symptomatic venous thromboembolism (REMOTEV), frail patients defined by age > 75 years, estimated glomerular filtration rate (eGFR) < 50 ml/min or low body weight ≤ 50 kg did not have more bleeding events compared to the non-frail patients.10 One of the major bleeding events was fatal (0.4%). This was similar to the EINSTEIN-DVT and EINSTEINPE studies where there was one case of fatal bleeding (< 0.1% in EINSTEIN-PE study).3,28 No fatal bleeding events occurred in patients receiving rivaroxaban in the REMOTEV study.10 Strengths and weaknesses This study has several strengths. We included all patients irrespective of underlying risk factors, trying to ascertain whether the findings of the phase 3 trials could be translated to daily patient care in an East African setting. Other randomised, control trials included strict inclusion criteria, with specific and well-matched patients. For instance, in the RECOVER 1 trial6 of dabigatran use versus warfarin, exclusion criteria included liver disease with aminotransferase levels of more than twice the upper limit of normal, eGFR of < 30 ml/min, a requirement for long-term antiplatelet therapy, recent unstable cardiovascular disease and high risk of bleeding. In the AMPLIFY trial9 of apixaban use versus warfarin, subjects with uncontrolled high blood pressure, known cancer subjects with planned long-term use of LMWH, low haemoglobin < 9 g/dl and eGFR of < 25 ml/min were excluded. In our trial only 3% of the subjects had cancer. Our study included all patients with VTE and therefore was more inclusive. The combination of both clinical and patient-reported outcomes was also a strength in our study. Getting this information made sure that most of the information was captured. Moreover, to our knowledge, this is the first study on NOAC use in Kenya. One limitation of this study is the lack of a direct comparator group such as VKA-treated patients. However, since there are several large-scale VKA studies, a reliable indirect comparison can be made with the DRESDEN NOAC study.17 Moreover, this being a retrospective study, data such as INR values would have been difficult to obtain, especially if the patients were on subsequent follow up at a different facility. We noted that the uptake of NOACs has increased over the past five years, with a subsequent decline in VKA use for VTE. The numbers could have been too few and those patients put on VKA may have differed in terms of patient characteristics and socio-economic class. There was selection bias and an imbalance of patients between treatment groups. Our study population mostly included patients on rivaroxaban and a few were on apixaban and dabigatran. Since it was a retrospective review of the patients’ charts, it was subject to missing information. The type and degree of bleeding may also have been insufficiently recorded. In terms of the data collected by telephone interviews, a standardised telephone questionnaire was used. This information was subject to recall bias and subjective evaluation of factors such as bleeding severity. However, interviews were carried out by appropriately trained professionals with the appropriate medical knowledge and further information could be sought from the patients’ medical practitioners. Conclusion The incidence rate of bleeding in our study was 17.24 per 100 person-years. The most common major bleeding site was the gastrointestinal system, while the most common type of minor bleeding was menorrhagia. The bleeding rates are similar to other real-world studies and phase 3 clinical trials. 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