Trial results comparing INR monitoring strategies for atrial fibrillation, deep vein thrombosis, and stroke were posted on ClinicalTrials.gov on 2026-03-03. The study, which enrolled 45 participants, found that a weekly capillary INR monitoring strategy achieved a mean 68% time in therapeutic range, compared to 43% with monthly venous monitoring.
Background
Atrial Fibrillation, Deep Vein Thrombosis, and Stroke are conditions often managed with Anti-Vitamin K (AVK) treatments, particularly in frail elderly patients. These patients, especially those residing in nursing homes, are at an increased risk for both embolic and hemorrhagic complications due to the narrow therapeutic window of AVK therapies. Effective monitoring of the International Normalized Ratio (INR) is therefore critical to maintain the 'time in therapeutic range' (TTR), which directly impacts the safety and efficacy of anticoagulation.
Trial design
This study, designated as Phase NA, was terminated and enrolled 45 participants. It investigated monitoring strategies for conditions including Atrial Fibrillation, Deep Vein Thrombosis, and Stroke. The trial aimed to compare the "time in therapeutic range" (TTR) of two INR monitoring strategies over 6 months in nursing home residents. The interventional group received weekly monitoring of capillary INR, while the control group received monthly monitoring of venous INR.
Key results
The trial reported several key measurements:
- Time in Therapeutic Range Using the Capillary International Normalized Range Weekly Monitoring Strategy:
- CONTROL GROUP: A mean of 43 percentage of time in therapeutic range (Standard Deviation 31).
- INTERVENTIONAL GROUP: A mean of 68 percentage of time in therapeutic range (Standard Deviation 21).
- Venous Thromboembolic Events Occurring During the 6-month Monitoring Period.:
- CONTROL GROUP: 0 Participants.
- INTERVENTIONAL GROUP: 0 Participants.
- Haemorrhagic Events Occurring During the 6-month Monitoring Period.:
- CONTROL GROUP: 2 Participants.
- INTERVENTIONAL GROUP: 7 Participants.
- Time in Therapeutic Range Using International Normalized Range Weekly Monitoring Strategy in Patients ≤90.:
- CONTROL GROUP: A mean of 43 percentage of time (Standard Deviation 28).
- INTERVENTIONAL GROUP: A mean of 72 percentage of time (Standard Deviation 23).
- Time in Therapeutic Range Using the International Normalized Range Weekly Monitoring Strategy in Patients >90.:
- CONTROL GROUP: A mean of 42 percentage of time (Standard Deviation 35).
- INTERVENTIONAL GROUP: A mean of 62 percentage of time (Standard Deviation 19).
- Cost-consequences Study on the Weekly INRc Monitoring Strategy:
- CONTROL GROUP: 0 Participants.
- INTERVENTIONAL GROUP: 0 Participants.
What this means
The results indicate that a weekly capillary INR monitoring strategy significantly increased the time in therapeutic range for patients with atrial fibrillation and other conditions in nursing homes. The interventional group achieved a mean TTR of 68%, a substantial improvement over the 43% seen in the control group. This benefit was observed across age subgroups, with patients aged ≤90 years showing a TTR of 72% and those >90 years showing 62% in the interventional group. While no venous thromboembolic events occurred in either group, the interventional group experienced more hemorrhagic events, with 7 participants compared to 2 in the control group. This suggests a potential trade-off between improved TTR and an increased risk of bleeding, which warrants careful consideration. The study was terminated, and these results provide important data for managing anticoagulation in this vulnerable population.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT05561244, titled "Weekly Monitoring Strategy of Capillary INR Versus Monthly Monitoring Strategy of Venous INR in Elderly Patients in a Nursing Home.", were posted on 2026-03-03 on clinicaltrials.gov.