Performance evaluation of the microINR® point-of-care INR-testing system

A review of the epidemiology of atrial fibrillation in sub-Saharan Africa

This systematic review summarizes the data on the prevalence, risk factors, complications, and management of atrial fibrillation (AF) in sub-Saharan Africa (SSA). Bibliographic databases were searched from inception to 31 May 2019, to identify all published studies providing data on AF in populations living in SSA. A total of 72 studies were included. The community-based prevalence of AF was 4.3% and 0.7% in individuals aged ≥40 years and aged ≥70 years, respectively. The prevalence of AF ranged between 6.7% and 34.8% in patients with ischemic stroke, between 9.5% and 46.8% in those with rheumatic heart disease (RHD), between 5% and 31.5% in patients with dilated cardiomyopathy. The main risk factors for AF were hypertension, affecting at least one-third of patients with AF, and valvular heart disease (12.3%-44.4%) and cardiomyopathy (~20%). Complications of AF included heart failure in about two thirds and stroke in 10% to 15% of cases. The use of anticoagulation for stroke prevention was suboptimal. Rate control was the most frequent therapeutic strategy, used in approximately 65% to 95% of AF patients, with approximately 80% of them achieving rate control. The management of AF was associated with exorbitant cost. In conclusion, AF seems to have a higher prevalence in the general population than previously thought and is mostly associated with hypertension, cardiomyopathy, and RHD in SSA. It is associated with a high incidence of heart failure and stroke. The management of AF is suboptimal in SSA, especially with a low uptake of oral anticoagulation.

Verification of the qLabs international normalized ratio point-of-care device for monitoring of patients attending an anticoagulation clinic

INTRODUCTION

In the developing world, point-of-care (POC) testing for international normalized ratio (INR) plays an important role in the monitoring of patients on long-term warfarin therapy with limited access to healthcare ensuring safe and effective anticoagulation. A newly developed POC device for INR measurement by healthcare workers is the handheld qLabs POC device^® (Micropoint Biotechnologies Incorporated, Guangdong, China).

METHODS

The qLabs POC device^® was evaluated in 262 patients attending an anticoagulation clinic with regards to accuracy and precision of the INR results. The results were compared to the results obtained on the Stago STA R Max^® coagulation analyzer (Stago Diagnostica, Paris, France) on a wide range of normal and abnormal results of clinical relevance.

RESULTS

The mean laboratory INR (2.50 ± 1.08) was significantly higher than the qLabs POC device^® INR (2.38 ± 1.07) (P < .0001). The correlation coefficient (r) was .88, the slope coefficient was 1.0 (CI, 0.8-1.2), and the intercept was -0.10 (CI, -0.50 to 0.30). The mean of the differences was -0.13% (CI, -0.19 to -0.06). Dosage concordance was 85.46% and clinical agreement was 92.37%. However, clinical agreement was 42.42% in the subgroup above the target range (>3.5). The imprecision was within acceptable limits (<5%) and the error message rate was 4.38%.

CONCLUSION

In conclusion, the qLabs POC device^® is accurate and precise with high levels of dosage concordance and clinical agreement for INR values within and below the target range.