Patient factors impacting on oral anticoagulation therapy among adult outpatients in a Kenyan referral hospital

Kizito Mariita, David G Nyamu, Carol K Maina, Peter N Karimi, Tom B Menge


Background: Patients’ factors such as knowledge on warfarin use are important in achieving desirable anticoagulation outcomes.

Objective: To assess the patient factors impacting on oral anticoagulation control among adult outpatients taking warfarin at Kenyatta National Hospital.

Methodology: A cross-sectional survey of 147out-patients on warfarin at Kenyatta National Hospital was carried out between March and April 2015. Data were collected using a pre-designed interviewer administered questionnaire. The data included patient characteristics such as indication and duration of anticoagulation; knowledge on anticoagulation; and international normalized ratio tests. The Oral Anticoagulation Knowledge test was used with a score of ≥75% indicating sufficient knowledge. Logistic regression was used to determine independent variables associated with anticoagulation control.

Results: Females were majority (74.9%) while optimal anticoagulation control was at 43.5%. Only 10.1% had sufficient knowledge on anticoagulation. Anticoagulation knowledge scores were associated with marital status (p=0.015), education level (p=0.014) and indication (p=0.032). Independent predictors of poor anticoagulation were female gender (p=0.011) and lower education level (p=0.005). Optimal anticoagulation control was, however, not associated with knowledge on anticoagulation (p=0.794).

Conclusion: Knowledge and control of anticoagulation among the patients are poor. Female gender and lower education level were predictors of poor anticoagulation. Provision of information on anticoagulation to patients on was warfarin is recommended.

Key words: Knowledge, Warfarin, Anticoagulation, International normalized ratio


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