Wits Journal of Clinical Medicine

A Histopathological Audit of Hyperparathyroidism in the South African Setting
The South African Breast and HIV Outcome (SABCHO) Study – Preliminary Results of a Multi-centre Prospective Trial
The Rates and Risk Factors for Local Recurrence of Phyllodes Tumours in a South African Population
Reliability and Versatility of the Wise Pattern, Medial Pedicle for Breast Reduction in South Africa
THINK: From MMED to Clinical Trial, a Promising Pilot
Gastrointestinal Cancer Patients Who Received Neoadjuvant and Adjuvant Therapy at Charlotte Maxeke Johannesburg Academic Hospital
The Profile of Colorectal Cancer Patients at CMJAH, Department of Surgery (April 2015 to March 2017)
An Audit of Colonoscopies Performed at Wits Donald Gordon Medical Centre and Helen Joseph Hospital
What Determines Outcome: Data Derived from a Prospective Cohort Study of Colorectal Cancer Patients Presenting to Four Witwatersrand University Hospitals
Monocyte Human Leucocyte Antigen Expression and CD4+/CD8+ ratio in the Second Hit of Acute Pancreatitis: Role in Disease Progression
Comparison of the Risk Factors and Initial Presenting Symptoms to the Stage of Disease in Pancreatic Ductal Adenocarcinoma at Chris Hani Baragwanath Academic Hospital

Background: Atrial fibrillation (AF) is a growing concern worldwide. In order to prevent AF-related adverse vascular events, adequate oral anticoagulation with warfarin is essential. The Rosendaal method has long been used to calculate time in therapeutic range (TTR) in clinical trials to assess the quality of anticoagulation but now suffers dwindling popularity due to its tedious method of calculation and inability to account for the duration spent in an out-of-range international normalized ratio (INR). Frequency in range (FIR) is being reassessed as to its value as it is easier to calculate.

Objectives: We aimed to compare FIR and TTR (using the Rosendaal method) as a measure to assess the quality of anticoagulation with warfarin in a cohort of 102 consecutive patients with valvular and non-valvular AF at a tertiary South African hospital. Secondary objectives were to assess the predictive ability of FIR to categorize patients with a TTR ≥ 65% as well as to compare the CHA₂DS₂VASc and HASBLED scores with TTRs and FIRs.

Methods: We retrospectively analysed the INR values for all patients over a 2-year period and calculated both individual and overall mean TTR and FIR and assessed the agreement between these parameters.

Results: The mean overall TTR was 58.1% ± 16% and the mean FIR was 50.8% ± 16.7%. The mean TTR was significantly higher than the mean FIR (p < 0.0001). At the individual level, FIR was positively correlated with TTR in a linear fashion (r = 0.93, p < 0.001). However, the Bland–Altman method plot indicated lack of agreement between TTR and FIR, with a bias of 7.4% (95% CI: 6.1%–8.6%) and limits of agreement −4.6% to 19.3%, standard deviation (SD) = 6.1%. A cut-off value of FIR ≥ 53.3% was found to be a good predictor of TTR ≥65%.

Conclusion: Our study shows that although TTR and FIR are highly correlated with the individual INR levels, they are not equal. The two methods cannot be used interchangeably to assess warfarin control, and TTR should probably remain the gold standard.

Background: A significant number of patients with acute coronary syndrome (ACS) are reported to suffer from anaemia. However, data relating to anaemia and clinical outcomes in patients presenting with ACS, particularly in Africa, are scarce. This study thus aimed to assess the prevalence of anaemia and its association with clinical characteristics and in-hospital mortality in patients presenting with ACS to a large urban public hospital in South Africa.

Methods: The study is a retrospective analysis of patients 18 years and above admitted with a diagnosis of ACS to the Charlotte Maxeke Johannesburg Hospital (CMJAH) over a two-and-a-half-year period between January 2010 and June 2012. Data on clinical characteristics, blood chemistry including haemoglobin (Hb) level, therapies received and in-hospital mortality was collected.

Results: A total of 431 ACS patients fulfilled the diagnostic criteria for ACS during the review period. The majority were males (72.2%) with a mean age of 58 ± 12.4 years. Anaemia was found to be present in 18.8% of all patients. Patients with anaemia were found to be significantly older, more likely to be female, have hypertension or diabetes and were more likely to be in a higher Killip functional class as compared to those not having anaemia. Anaemic patients were also less likely to receive optimal medical therapy for ACS (60.5% vs. 72.7%, p < 0.001). Killip class ≥3 (p < 0.001), atrial fibrillation (p < 0.045) and haemoglobin (Hb) < 11.4 g/dl (p < 0.0001) were significantly associated with mortality. However, only Hb of <11.4 g/dl was found to be an independent predictor of mortality and had more than fourfold increased risk compared to those with normal Hb (CI – 1.393–13.041; RR – 4.262; p < 0.011).

Conclusion: Anaemia was present in almost one-fifth of patients presenting with ACS. Furthermore it was significantly associated with diabetes, hypertension, older age, female sex and Killip class ≥3. Anaemic patients were also less likely to receive optimal medical therapy. Importantly, a haemoglobin level <11.4 g/dl was found to be an independent predictor of mortality. Simple serial measurement of Hb is recommended in patients presenting with ACS and should be incorporated into the risk stratification of patients with ACS.