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Comparison of two approaches of INR-follow-up and determinants of INR-stability
Insights
Managing atrial fibrillation (AF) patients on coumarins requires close international normalized ratio (INR) monitoring. Both general practitioner (GP) and hospital hematologist follow-up yield similar INR control, but GP care is more cost-effective for patients.
Area of Science:
- Cardiology
- Pharmacology
- Health Services Research
Background:
- Patients with atrial fibrillation (AF) on coumarin therapy require regular international normalized ratio (INR) monitoring.
- Monitoring can be managed by general practitioners (GPs) or hospital-based hematologists.
Purpose of the Study:
- To compare the efficacy and cost-effectiveness of INR monitoring by GPs versus hematologists in AF patients.
- To identify factors associated with stable INR control.
Main Methods:
- A cross-sectional study at UZ Brussel involving 113 AF patients.
- Patients were grouped based on INR monitoring by either their GP (n=71) or a hematologist (n=42).
- Analysis focused on time in therapeutic range (TTR) and determinants of INR stability.
Main Results:
- No significant difference in TTR between GP and hematologist groups.
- GP group had more INR values < 2.0 (P=0.044); hematologist group had more INR values > 3.0 (P=0.038).
- Lower out-of-pocket costs for patients under GP care; time since AF diagnosis predicted higher TTR.
Conclusions:
- Both GP and hematologist monitoring achieve comparable TTR for AF patients on coumarins.
- GP follow-up offers lower patient costs.
- Time since AF diagnosis is a key factor for stable INR control.
Introduction:
Patients with atrial fibrillation (AF) and treated with coumarins need a close follow-up of the international normalized ratio (INR)-values. This can be done by the general practitioner (GP) or by a haematologist in an outpatient hospital clinic.
Objective:
To compare both ways of follow-up and to investigate determinants of stable INR-patterns.
Methods:
Cross-sectional single-centre study in patients with AF treated at the UZ Brussel, a university hospital in Brussels. Of the 113 patients included in the study, 71 had their INR followed-up by their GP and 42 similar patients were followed-up by a haematologist. Data of these 113 patients were further analysed to identify possible determinants for stable INR-values.
Results:
The time in therapeutic range (TTR) did not significantly differ between both groups. However, patients in the GP-group had significantly more INR-values under 2.0 compared to patients from the haematologist-group (P = 0.044), whereas patients in the haematologist-group had significantly more INR-values above 3.0 compared to patients from the GP-group (P = 0.038). Reimbursement costs of both ways of follow-up were comparable, but the out-of-pocket costs for the patient were lower in the GP-group. The time since AF diagnosis was the only significant determinant predicting a higher TTR.
Conclusion:
Both approaches of follow-up seem to lead to the same TTR, yielding no reason to advocate one approach above the other. However, the patient costs were lower when followed-up by the GP.
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