Time in Therapeutic Range and Percentage of International Normalized Ratio in the Therapeutic Range as a Measure of Quality of Anticoagulation Control in Patients With Atrial Fibrillation

2016 ◽  
Vol 32 (10) ◽  
pp. 1247.e23-1247.e28 ◽  
Author(s):  
Pak-Hei Chan ◽  
Wen-Hua Li ◽  
Jo-Jo Hai ◽  
Esther W. Chan ◽  
Ian C.K. Wong ◽  
...  
2020 ◽  
Vol 103 (6) ◽  
pp. 548-552

Objective: To predict the quality of anticoagulation control in patients with atrial fibrillation (AF) receiving warfarin in Thailand. Materials and Methods: The present study retrospectively recruited Thai AF patients receiving warfarin for three months or longer between June 2012 and December 2017 in Central Chest Institute of Thailand. The patients were classified into those with SAMe-TT₂R₂ of 2 or less, and 3 or more. The Chi-square test or Fisher’s exact test was used to compare the proportion of the patients with poor time in therapeutic range (TTR) between the two groups of SAMe-TT₂R₂ score. The discrimination performance of SAMe-TT₂R₂ score was demonstrated with c-statistics. Results: Ninety AF patients were enrolled. An average age was 69.89±10.04 years. Most patients were persistent AF. An average CHA₂DS₂-VASc, SAMe-TT₂R₂, and HAS-BLED score were 3.68±1.51, 3.26±0.88, and 1.98±0.85, respectively. The present study showed the increased proportion of AF patients with poor TTR with higher SAMe-TT₂R₂ score. The AF patients with SAMe-TT₂R₂ score of 3 or more had a larger proportion of patients with poor TTR than those with SAMe-TT₂R₂ score of 2 or less with statistical significance when TTR was below 70% (p=0.03) and 65% (p=0.04), respectively. The discrimination performance of SAMe-TT₂R₂ score was demonstrated with c-statistics of 0.60, 0.59, and 0.55 when TTR was below 70%, 65% and 60%, respectively. Conclusion: Thai AF patients receiving warfarin had a larger proportion of patients with poor TTR when the SAMe-TT₂R₂ score was higher. The score of 3 or more could predict poor quality of anticoagulation control in those patients. Keywords: Time in therapeutic range, Poor quality of anticoagulation control, Warfarin, SAMe-TT₂R₂, Labile INR


2021 ◽  
Vol 8 ◽  
Author(s):  
Nur Azyyati Zawawi ◽  
Izzati Abdul Halim Zaki ◽  
Long Chiau Ming ◽  
Hui Poh Goh ◽  
Hanis Hanum Zulkifly

Vitamin K antagonist such as warfarin reduces the risk of stroke in atrial fibrillation (AF) patients. Since warfarin has a narrow therapeutic index, its administration needs to be regularly monitored to avoid any adverse clinical outcomes such as stroke and bleeding. The quality of anticoagulation control with warfarin therapy can be measured by using time in therapeutic range (TTR). This review focuses on the prevalence of AF, quality of anticoagulation control (TTR) and adverse clinical outcome in AF patients within different ethnic groups receiving warfarin therapy for stroke prevention. A literature search was conducted in Embase and PubMed using keywords of “prevalence,” “atrial fibrillation,” “stroke prevention,” “oral anticoagulants,” “warfarin,” “ethnicities,” “race” “time in therapeutic range,” “adverse clinical outcome,” “stroke, bleeding.” Articles published by 1st February 2020 were included. Forty-one studies were included in the final review consisting of AF prevalence (n = 14 studies), time in therapeutic range (n = 18 studies), adverse clinical outcome (n = 9 studies) within different ethnic groups. Findings indicate that higher prevalence of AF but better anticoagulation control among the Whites as compared to other ethnicities. Of note, non-whites had higher risk of strokes and bleeding outcomes while on warfarin therapy. Addressing disparities in prevention and healthcare resource allocation could potentially improve AF-related outcomes in minorities.


2017 ◽  
Vol 117 (12) ◽  
pp. 2291-2299 ◽  
Author(s):  
Anders Bonde ◽  
Gregory Lip ◽  
Anne-Lise Kamper ◽  
Laila Staerk ◽  
Christian Torp-Pedersen ◽  
...  

AbstractPatients with severely reduced renal function have been excluded from randomized controlled trials of oral anticoagulation in atrial fibrillation (AF). Warfarin treatment in this population is controversial and data on anticoagulation control and the impact on adverse outcomes are needed. By individual-level linkage of nationwide registries, we identified all patients discharged from hospitals with AF in Denmark between 1997 and 2011. Patients with available serum creatinine tests were categorized according to the estimated glomerular filtration rate (eGFR). Time in therapeutic range (TTR) was calculated using the Rosendaal method. The risk of stroke and bleeding was estimated using multivariable Cox regression analyses with eGFR and TTR estimated time dependently throughout follow-up. We identified 10,423 warfarin-treated AF patients with available international normalized ratio and creatinine tests; 5,527 with eGFR > 60 mL/min/1.73 m2, 4,524 with eGFR 30–60 mL/min/1.73 m2 and 372 with eGFR < 30 mL/min/1.73 m2. Median TTR was 66.7, 61.2 and 49.7% in patients with eGFR > 60, 30–59 and <30 mL/min/1.73 m2, respectively. A TTR < 70% was associated with a higher risk of stroke/thromboembolism (hazard ratio [HR]: 1.39; 95% confidence interval [CI]: 1.20–1.60) and bleeding (HR: 1.22; 95% CI: 1.05–1.42) among patients with eGFR of 30 to 59 and a trend towards higher risk of stroke/thromboembolism (HR: 1.24; 95% CI: 0.86–1.80) and bleeding (HR: 1.17; 95% CI: 0.83–1.65) among patients with eGFR < 30 mL/min/1.73 m2. In conclusion, warfarin-treated AF patients with reduced renal function have suboptimal anticoagulation control which was related to the risk of adverse outcomes.


2020 ◽  
Vol 9 (6) ◽  
pp. 1698 ◽  
Author(s):  
Rungroj Krittayaphong ◽  
Thoranis Chantrarat ◽  
Roj Rojjarekampai ◽  
Pongpun Jittham ◽  
Poom Sairat ◽  
...  

Background: Warfarin remains the most commonly used oral anticoagulant (OAC) in Thailand for stroke prevention among patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to investigate the relationship between time in therapeutic range (TTR) after warfarin initiation and clinical outcomes of NVAF. Methods: TTR was calculated by the Rosendaal method from international normalized ratio (INR) data acquired from a nationwide NVAF registry in Thailand. Patients were followed-up every six months. The association between TTR and clinical outcomes was analyzed. Results: There was a total of 2233 patients from 27 hospitals. The average age was 68.4 ± 10.6 years. The average TTR was 53.56 ± 26.37%. Rates of ischemic stroke/TIA, major bleeding, ICH, and death were 1.33, 2.48, 0.76, and 3.3 per 100 person-years, respectively. When patients with a TTR < 65% were compared with those with TTR ≥ 65%, the adjusted hazard ratios (aHR) for the increased risks of ischemic stroke/TIA, major bleeding, ICH, and death were 3.07, 1.90, 2.34, and 2.11, respectively. Conclusion: Poor TTR control is associated with adverse clinical outcomes in patients with NVAF who were on warfarin. Efforts to ensure good TTR (≥65%) after initiation of warfarin are mandatory to minimize the risk of adverse clinical outcomes.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
H Zulkifly ◽  
D Pastori ◽  
G Y H Lip ◽  
D Lane

Abstract Introduction Good quality of anticoagulation in patients with valvular heart disease (VHD) is needed to reduce ischaemic complications. There is limited evidence on factors affecting anticoagulation control in patients implanted with mechanical or tissue prosthetic valve(s). Objective To examine quality, factors affecting anticoagulation control and all-cause death in VHD patients with and without atrial fibrillation (AF) receiving a vitamin K antagonist (VKA) oral anticoagulant. The relationship between INR control with all-cause death and ≥1 adverse clinical events (ACE) [thromboembolism, bleeding, cardiovascular hospitalisation and all-cause death] were explored. Methods Anticoagulation control of 456 VHD patients [164 (36%) with AF and 290 (64%) without AF] referred to a hospital-based anticoagulation clinic were assessed retrospectively by time in therapeutic range (TTR) (Rosendaal) and percentage of INRs in range (PINRR) for a median of (IQR) 6.2 years (3.3–8.5). VHD was defined by the presence of mechanical or tissue prosthetic valve at either the mitral or aortic site or both. Results Mean (SD) age 51 (14.7), 64.5% male, mean (SD) CHA2DS2-VASc score 2.0 (1.4), 96.1% mechanical prosthesis and 64% aortic valve replacement. VHD patients with AF had lower mean TTR and PINRR, lower proportion of optimal TTR (i.e.≥70%) despite similar number of INR tests compared to VHD patients without AF [Table 1]. Predictors of poor TTR on multivariate logistic regression analysis were female sex, AF and anaemia/bleeding history. Significantly higher proportions of VHD patients with AF died [Table 1]. More deaths (13.1% vs. 4.1%; p=0.011) and ≥1 ACE (42.7% vs. 27.6%; p=0.006) were seen in VHD patients with TTR <70% vs. TTR≥70%, respectively. Table 1 N (%) Total (N=456) AF (N=164) No AF (N=290) p-value Mean (SD) TTR 58.5 (14.6) 55.7 (14.2) 60.1 (14.6) 0.002 TTR ≥70% 98 (21.5) 23 (14.0) 75 (25.7) 0.004 Mean (SD) PINRR 50.1 (13.8) 47.4 (13.5) 51.6 (13.7) 0.002 Mean (SD) INR tests 96.2 (55.3) 100.7 (58.8) 93.7 (53.1) 0.19 All-cause death 51 (11.2) 34 (20.7) 17 (5.8) <0.001 AF: Atrial fibrillation; IQR: interquartile range; PINRR: percentage of INRs in range; SD: standard deviation; TTR: Time in therapeutic range. Conclusion The quality of anticoagulation in VHD patients with AF was low. The presence of AF, anaemia/bleeding history and female sex independently predicted poor TTR. All-cause death was more common in VHD patients with AF and poor TTR. Closer INR monitoring is needed especially in VHD patients with AF to improve anticoagulation control and prevent adverse clinical outcomes. Acknowledgement/Funding Kementerian Pendidikan Malaysia and Universiti Teknologi MARA for PhD study but not directly for work under consideration


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
A N Bonde ◽  
J Bjerre ◽  
M Proietti ◽  
G Gislason ◽  
G Y H Lip ◽  
...  

Abstract Background Efficacy and safety of vitamin K antagonists (VKAs) depend on quality of anticoagulation control, usually measured as time in therapeutic range (TTR). Factors that predict low TTR on VKAs could be used to identify patients who might benefit from interventions, or who would be better treated with a non-VKA oral anticoagulant (NOAC). Patients living alone may have difficulties in taking their medications, managing their diets, or coming to clinic for monitoring. Purpose To assess influence of cohabitation status on TTR with VKA among men and women. Methods We identified all Danish patients with atrial fibrillation (AF) who initiated VKA between 1997 and 2012, and studied patients who had 6 months of continuous VKA use and international normalized ratio (INR) monitoring. Patients were divided according to sex and whether they lived alone or with others. We calculated TTR using the Rosendaal method, and INR variability using Fihns method. We used a linear regression model to test for associations between TTR and covariates, and adjusted for age, income, medications and comorbidities. Results We identified 4,772 AF patients with 6 months of continuous VKA use and INR monitoring. 713 (15%) were men living alone, 1,073 (23%) were women living alone, 2,164 (45%) were men not living alone and 822 (17%) were women not living alone. INR was measured a median of 11 (interquartile range 8–15) times during the 180 days of VKA use, but men who lived alone had 0.6 (95% confidence interval (CI): 0.2 to 1.2) fewer INR measurements during the period. Median TTR was lowest among men living alone (57.2%), followed by women living alone (58.8%), women not living alone (61.0%) and men not living alone (62.5%). After multivariable adjustment, men who lived alone had a 3.6% (CI −5.6 to −1.6) lower TTR compared with men not living alone, but women who lived alone did not have significantly lower TTR (P=0.80) compared with women not living alone. Living alone had significantly greater effect on TTR among men than among women (interaction P=0.02). Men living alone also had higher adjusted INR variability (0.2, CI 0.0 to 0.4) compared with men not living alone. Conclusion Living alone was significantly related to low quality of anticoagulation control among men, but not among women. Acknowledgement/Funding this study was funded by an unrestricted grant from the Capital Region of Denmark, Foundation for Health Research


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Proietti ◽  
G F Romiti ◽  
B Olshansky ◽  
G Y H Lip

Abstract Introduction Quality of anticoagulation control is essential to ensure better clinical outcomes in patients with atrial fibrillation (AF). Time in therapeutic range (TTR) is recommended as a measure of the quality of anticoagulation control. The International normalized ratio (INR) variability has been suggested as an alternative index, even though large independent validations for this index are still lacking. Purpose To provide validation of clinical usefulness of INR variability as a measure of the quality of anticoagulation control in a large cohort of AF patients. Methods Data from the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial were analysed. INR variability was defined as the standard deviation (SD) of mean INR values [INR-SD] recorded throughout the follow-up observation for each patient. All patients with available INR values were included in the analysis. Stroke, major bleeding, cardiovascular (CV) death and all-cause death were study outcomes. Results Among the original 4060 patients, a total of 3185 (78.4%) were available for analysis. Mean (SD) INR-SD was 0.58 (0.25). According to INR-SD patients were categorized into four quartiles. Mean (SD) CHA2DS2-VASc score was increased (p=0.040), with no difference in proportions of CHA2DS2-VASc ≥2 (p=0.582) between the subgroups. A significant inverse correlation was found between INR-SD and TTR (Spearman's Rho: −0.536, p<0.001). Continuous INR-SD, after multiple adjustments, was inversely associated with TTR (standardized beta: −0.451, p<0.001) and directly associated with SAMe-TT2R2score (standardized beta: 0.084, p<0.001). A fully adjusted Cox multivariate regression analysis found that INR-SD was directly associated with increased risk of stroke, major bleeding and all-cause death (Table). An INR-SD ≥0.85 was directly associated with all the study outcomes, on multivariate analysis (Table). Cox Regression Analysis INR-SD INR-SD ≥0.85 HR (95% CI) HR (95%) Stroke 2.52 (1.34–4.67) 1.62 (1.00–2.63) Major Bleeding 2.43 (1.49–3.96) 1.61 (1.10–2.36) CV Death 1.50 (0.87–2.59) 1.54 (1.07–2.24) All-Cause Death 1.79 (1.21–2.66) 1.55 (1.17–2.05) CI = Confidence Interval; CV = Cardiovascular; HR = Hazard Ratio; INR-SD = International Normalized Ratio Standard Deviation. Conclusions INR variability, expressed as INR-SD, was significantly correlated and associated with TTR. Both continuous INR-SD and INR-SD ≥0.85 were significantly associated with a higher risk of all study adverse outcomes. Acknowledgement/Funding None


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