Trial Outcomes & Findings for Improving Anticoagulation Control in VISN 1 (NCT NCT01653405)
NCT ID: NCT01653405
Last Updated: 2019-04-16
Results Overview
We compared TTR after the intervention to before the intervention. We used a difference in differences analysis to compare the absolute percentage change over time in the intervention group vs. the control group.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
1260576 participants
Primary outcome timeframe
Baseline and 4 years
Results posted on
2019-04-16
Participant Flow
Unit of analysis: VA sites
Participant milestones
| Measure |
VISN1 (Intervention Group)
VA patients receiving care at anticoagulation clinics at 8 sites within VISN 1
|
Outside VISN1 (Control Group)
VA patients receiving care at anticoagulation clinics at 116 sites outside of VISN 1.
|
|---|---|---|
|
Overall Study
STARTED
|
11794 8
|
1248782 116
|
|
Overall Study
COMPLETED
|
8029 8
|
179979 116
|
|
Overall Study
NOT COMPLETED
|
3765 0
|
1068803 0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Improving Anticoagulation Control in VISN 1
Baseline characteristics by cohort
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites in VISN 1.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
Total
n=188008 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
77.7 years
STANDARD_DEVIATION 11.0 • n=99 Participants
|
75.3 years
STANDARD_DEVIATION 11.2 • n=107 Participants
|
75.4 years
STANDARD_DEVIATION 11.2 • n=206 Participants
|
|
Sex: Female, Male
Female
|
181 Participants
n=99 Participants
|
4340 Participants
n=107 Participants
|
4521 Participants
n=206 Participants
|
|
Sex: Female, Male
Male
|
7848 Participants
n=99 Participants
|
175639 Participants
n=107 Participants
|
183487 Participants
n=206 Participants
|
|
Average TTR
|
66.4 percentage of time in target INR range
STANDARD_DEVIATION 3.4 • n=99 Participants
|
65.9 percentage of time in target INR range
STANDARD_DEVIATION 3.7 • n=107 Participants
|
65.9 percentage of time in target INR range
STANDARD_DEVIATION 3.7 • n=206 Participants
|
|
Percentage of instances where INR<=1.5 was followed by a second INR within 7 days
|
36 percentage of instances
n=99 Participants
|
28 percentage of instances
n=107 Participants
|
28 percentage of instances
n=206 Participants
|
|
Percentage of instances where an INR >= 4.0 was followed by a second INR within 7 days
|
50 percentage of instances
n=99 Participants
|
42 percentage of instances
n=107 Participants
|
42 percentage of instances
n=206 Participants
|
|
Gaps in monitoring per patient-year
|
0.31 gaps per patient-year
STANDARD_DEVIATION 0.15 • n=99 Participants
|
0.37 gaps per patient-year
STANDARD_DEVIATION 0.18 • n=107 Participants
|
0.37 gaps per patient-year
STANDARD_DEVIATION 0.18 • n=206 Participants
|
|
Percentage of patients whose mean INR value was between 2.3 and 2.7
|
50 percentage of patients
n=99 Participants
|
47 percentage of patients
n=107 Participants
|
47 percentage of patients
n=206 Participants
|
PRIMARY outcome
Timeframe: Baseline and 4 yearsPopulation: Patients receiving care at specified sites. Patient-level analyses were aggregated to the site level.
We compared TTR after the intervention to before the intervention. We used a difference in differences analysis to compare the absolute percentage change over time in the intervention group vs. the control group.
Outcome measures
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites within VISN 1. We provided sites with a system to measure processes of care, along with targeted audit and feedback. We focused on processes of care associated with site level anticoagulation control, including prompt follow-up after out-of-range international normalized ratio (INR) values, minimizing loss to follow-up, and use of guideline-concordant INR target ranges.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
|---|---|---|
|
Percent Change in Time in Therapeutic Range (TTR)
|
2.8 percent change
|
0.5 percent change
|
SECONDARY outcome
Timeframe: Baseline and 4 yearsWe compared the rate of 56-day gaps per patient year in the pre-intervention and post-intervention period. We used a difference in differences analysis to compare the intervention and control group. We are reporting absolute change.
Outcome measures
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites within VISN 1. We provided sites with a system to measure processes of care, along with targeted audit and feedback. We focused on processes of care associated with site level anticoagulation control, including prompt follow-up after out-of-range international normalized ratio (INR) values, minimizing loss to follow-up, and use of guideline-concordant INR target ranges.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
|---|---|---|
|
Change in Gaps in Monitoring Per Patient-year Among Patients Receiving Anticoagulation With Warfarin
|
-0.03 gaps per patient year
Standard Deviation 0.10
|
-0.01 gaps per patient year
Standard Deviation 0.09
|
SECONDARY outcome
Timeframe: Baseline and 4 yearsWe compared the percentage of patients with follow-up within 7 days before and after the intervention. We used a difference in differences analysis to compare the intervention and control groups.
Outcome measures
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites within VISN 1. We provided sites with a system to measure processes of care, along with targeted audit and feedback. We focused on processes of care associated with site level anticoagulation control, including prompt follow-up after out-of-range international normalized ratio (INR) values, minimizing loss to follow-up, and use of guideline-concordant INR target ranges.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
|---|---|---|
|
Change in Percentage of Patients With Follow-up Within 7 Days After a High INR Value (>4.0)
|
15 percentage change
|
0 percentage change
|
SECONDARY outcome
Timeframe: Baseline and 4 yearsWe compared the percentage of patients before and after the intervention. We used a difference in differences analysis to compare the intervention and control groups. Absolute percentage is reported.
Outcome measures
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites within VISN 1. We provided sites with a system to measure processes of care, along with targeted audit and feedback. We focused on processes of care associated with site level anticoagulation control, including prompt follow-up after out-of-range international normalized ratio (INR) values, minimizing loss to follow-up, and use of guideline-concordant INR target ranges.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
|---|---|---|
|
Change in Percentage of Patients With Follow-up Within 7 Days After a Low INR Value (1.5 or Lower)
|
15 percentage change
|
2 percentage change
|
SECONDARY outcome
Timeframe: Baseline and 4 yearsWe compared the absolute percentage of patients with a mean INR of 2.3 - 2.7 before and after the intervention. We used a difference in differences analysis to compare the intervention and control groups.
Outcome measures
| Measure |
Intervention Group
n=8029 Participants
VA patients receiving anticoagulation clinic services at 8 sites within VISN 1. We provided sites with a system to measure processes of care, along with targeted audit and feedback. We focused on processes of care associated with site level anticoagulation control, including prompt follow-up after out-of-range international normalized ratio (INR) values, minimizing loss to follow-up, and use of guideline-concordant INR target ranges.
|
Control Group
n=179979 Participants
VA patients receiving anticoagulation clinic services at 116 sites outside of VISN 1.
|
|---|---|---|
|
Percentage of Patients With Mean INR Value Between 2.3 - 2.7
|
6 percentage change
|
1 percentage change
|
Adverse Events
VISN1 (Intervention Group)
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Outside VISN1 (Control Group)
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place