Point-of-Care International Normalized Ratio (INR) Monitoring Devices for Patients on Long-term Oral Anticoagulation Therapy: An Evidence-Based Analysis. The Impact of Patient Self-Testing of Prothrombin Time for Managing Anticoagulation: Rationale and Design of VA Cooperative Study #481—The Home INR Study (THINRS) Randomized controlled trial of supervised patient self-testing of warfarin therapy using an internet-based expert system. A prospective controlled trial comparing weekly self-testing and self-dosing with the standard management of patients on stable oral anticoagulation. Patient self-management of warfarin therapy: pragmatic feasibility study in Canadian primary care. INR Self-Management Permits Lower Anticoagulation Levels After Mechanical Heart Valve Replacement SMART: Self-Management of Anticoagulation, a Randomised Trial [ISRCTN19313375] Monitoring anticoagulation in atrial fibrillation Evaluation of a portable prothrombin time monitor for home use by patients who require long-term oral anticoagulant therapy. A randomised control trial of patient self‐management of oral anticoagulation compared with patient self‐testing Patient self‐testing is a reliable and acceptable alternative to laboratory INR monitoring A randomized controlled trial of shared care versus routine care for patients receiving oral anticoagulant therapy. Direct-to-patient expert system and home INR monitoring improves control of oral anticoagulation Is home warfarin self-management effective? Results of the randomised Self-Management of Anticoagulation Research Trial. International normalized ratio self-management lowers the risk of thromboembolic events after prosthetic heart valve replacement. Lower versus standard intensity oral anticoagulant therapy (OAT) in elderly warfarin-experienced patients with non-valvular atrial fibrillation. A randomised controlled trial of patient self management of oral anticoagulation treatment compared with primary care management
UNLABELLED SUBJECT OF THE EVIDENCE -BASED ANALYSIS : The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care ( POC ) international normalized ratio ( INR ) monitoring devices for patients on long-term oral anticoagulation therapy ( OAT ) .  CLINICAL NEED TARGET POPULATION AND CONDITION Long-term OAT is typically required by patients with mechanical heart valves , chronic atrial fibrillation , venous thromboembolism , myocardial infa rct ion , stroke , and /or peripheral arterial occlusion . It is estimated that approximately 1 % of the population receives anticoagulation treatment and , by applying this value to Ontario , there are an estimated 132,000 patients on OAT in the province , a figure that is expected to increase with the aging population . Patients on OAT  are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range . This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses . Optimal INR scores depend on the underlying indication for treatment and patient level characteristics , but for most patients the therapeutic range is an INR score of between 2.0 and 3.0 . The current st and ard of care in Ontario for patients on long-term OAT is laboratory-based INR determination with management carried out by primary care physicians or anticoagulation clinics ( ACCs ) . Patients also regularly visit a hospital or community-based facility to provide a venous blood sample s ( venipuncture ) that are then sent to a laboratory for INR analysis . Experts , however , have commented that there may be under-utilization of OAT due to patient factors , physician factors , or regional practice variations and that sub-optimal patient management may also occur . There is currently no population -based Ontario data to permit the assessment of patient care , but recent systematic review s have estimated that less that 50 % of patients receive OAT on a routine basis and that patients are in the therapeutic range only 64 % of the time . OVERVIEW OF POC INR DEVICES POC INR devices offer an alternative to laboratory-based testing and venipuncture , enabling INR determination from a fingerstick sample of whole blood . Independent evaluations have shown POC devices to have an acceptable level of precision . They permit INR results to be determined immediately , allowing for more rapid medication adjustments . POC devices can be used in a variety of setting s including physician offices , ACCs , long-term care facilities , pharmacies , or by the patients themselves through self-testing ( PST ) or self-management ( PSM ) techniques . With PST , patients measure their INR values and then contact their physician for instructions on dose adjustment , whereas with PSM , patients adjust the medication themselves based on pre-set algorithms . These models are not suitable for all patients and require the identification and education of suitable c and i date s. Potential advantages of POC devices include improved convenience to patients , better treatment compliance and satisfaction , more frequent monitoring and fewer thromboembolic and hemorrhagic complications . Potential disadvantages of the device include the tendency to underestimate high INR values and overestimate low INR values , low thromboplastin sensitivity , inability to calculate a mean normal PT , and errors in INR determination in patients with antiphospholipid antibodies with certain instruments . Although treatment satisfaction and quality of life ( QoL ) may improve with POC INR monitoring , some patients may experience increased anxiety or preoccupation with their disease with these strategies . EVIDENCE -BASED ANALYSIS METHODS RESEARCH QUESTIONS 1 . EffectivenessDoes POC INR monitoring improve clinical outcomes in various setting s compared to st and ard laboratory-based testing?Does POC INR monitoring impact patient satisfaction , QoL , compliance , acceptability , convenience compared to st and ard laboratory-based INR determination ? Setting s include primary care setting s with use of POC INR devices by general practitioners or nurses , ACCs , pharmacies , long-term care homes , and use by the patient either for PST or PSM . 2 . Cost-effectivenessWhat is the cost-effectiveness of POC INR monitoring devices in various setting s compared to st and ard laboratory-based INR determination ? INCLUSION CRITERIA English- language RCTs , systematic review s , and meta-analysesPUBLICATION DATE S : 1996 to November 25 , 2008 POPULATION : patients on OATINTERVENTION : anticoagulation monitoring by POC INR device in any setting including anticoagulation clinic , primary care ( general practitioner or nurse ) , pharmacy , long-term care facility , PST , PSM or any other POC INR strategy MINIMUM SAMPLE SIZE : 50 patients Minimum follow-up period : 3 monthsCOMPARATOR : usual care defined as venipuncture blood draw for an INR laboratory test and management provided by an ACC or individual practitioner OUTCOMES Hemorrhagic events , thromboembolic events , all-cause mortality , anticoagulation control as assessed by proportion of time or values in the therapeutic range , patient reported outcomes including satisfaction , QoL , compliance , acceptability , convenience EXCLUSION CRITERIA Non- RCTs , before-after studies , quasi-experimental studies , observational studies , case reports , case series , editorials , letters , non- systematic review s , conference proceedings , abstract s , non-English articles , duplicate publications Studies where POC INR devices were compared to laboratory testing to assess test accuracy Studies where the POC INR results were not used to guide patient management METHOD OF REVIEW A search of electronic data bases ( OVID MEDLINE , MEDLINE In-Process & Other Non-Indexed Citations , EMBASE , The Cochrane Library , and the International Agency for Health Technology Assessment [ INAHTA ] data base ) was undertaken to identify evidence published from January 1 , 1998 to November 25 , 2008 . Studies meeting the inclusion criteria were selected from the search results . Reference lists of selected articles were also checked for relevant studies . SUMMARY OF FINDINGS Five existing review s and 22 articles describing 17 unique RCTs met the inclusion criteria . Three RCTs examined POC INR monitoring devices with PST strategies , 11 RCTs examined PSM strategies , one RCT included both PST and PSM strategies and two RCTs examined the use of POC INR monitoring devices by health care professionals .  ANTICOAGULATION CONTROL Anticoagulation control is measured by the percentage of time INR is within the therapeutic range or by the percentage of INR values in the therapeutic range . Due to the differing method ologies and reporting structures used , it was deemed inappropriate to combine the data and estimate whether the difference between groups would be significant . Instead , the results of individual studies were weighted by the number of person-years of observation and then pooled to calculate a summary measure . Across most studies , patients in the intervention groups tended to have a higher percentage of time and values in the therapeutic target range in comparison to control patients . When the percentage of time in the therapeutic range was pooled across studies and weighted by the number of person-years of observation , the difference between the intervention and control groups was 4.2 % for PSM , 7.2 % for PST and 6.1 % for POC use by health care practitioners . Overall , intervention patients were in the target range 69 % of the time and control patients were in the therapeutic target range 64 % of the time leading to an overall difference between groups of roughly 5 % . MAJOR COMPLICATIONS AND DEATHS There was no statistically significant difference in the number of major hemorrhagic events between patients managed with POC INR monitoring devices and patients managed with st and ard laboratory testing ( OR = 0.74 ; 95 % CI : 0.52- 1.04 ) . This difference was non-significant for all POC strategies ( PSM , PST , health care practitioner ) . Patients managed with POC INR monitoring devices had significantly fewer thromboembolic events than usual care patients ( OR = 0.52 ; 95 % CI : 0.37 - 0.74 ) . When divided by POC strategy , PSM result ed in significantly fewer thromboembolic events than usual care ( OR = 0.46 . ; 95 % CI : 0.29 - 0.72 ) . The observed difference in thromboembolic events for PSM remained significant when the analysis was limited to major thromboembolic events ( OR = 0.40 ; 95 % CI : 0.17 - 0.93 ) , but was non-significant when the analysis was limited to minor thromboembolic events ( OR = 0.73 ; 95 % CI : 0.08 - 7.01 ) . PST and GP/Nurse strategies did not result in significant differences in thromboembolic events , however there were only a limited number of studies examining these interventions . No statistically significant difference was observed in the number of deaths between POC intervention and usual care control groups ( OR = 0.67 ; 95 % CI : 0.41 - 1.10 ) . This difference was non-significant for all POC strategies . Only one study reported on survival with 10-year survival rate of 76.1 % in the usual care control group compared to 84.5 % in the PSM group ( P=0.05 ) . ES Table 1 : Summary Results of Meta-Analyses of Major Complications and Deaths in POC INR Monitoring Studies EventNo . of trials ( patients ) OR(M-H , R and om Effects)95 % CIMajor Haemorrhages16 (5057)0.740.52 to 1.04Thromboembolic events16 (5057)0.520.37 to 0.74Deaths11 (2906)0.670.41 to 1.10 PATIENT SATISFACTION AND QUALITY OF LIFE : Quality of life measures were reported in eight studies comparing POC INR monitoring to st and ard laboratory testing using a variety of measurement tools . It was thus not possible to calculate a quantitative summary measure . The majority of studies reported favourable impacts of POC INR monitoring on QoL and found better treatment satisfaction with POC monitoring . Results from a pre- analysis patient and caregiver focus group conducted in Ontario also indicated improved patient QoL with POC monitoring . ( Background : Anticoagulation ( AC ) with warfarin reduces the risk of thromboembolism ( TE ) in a variety of applications , yet despite compelling evidence of the value and importance of high quality AC , warfarin remains underused , and dosing is often suboptimal . Approaches to improve AC quality include ( 1 ) an AC service ( ACS ) , which allows the physician to delegate day-to-day details of AC management to another provider dedicated to AC care , and ( 2 ) incorporating into the treatment plan patient self-testing ( PST ) under which , after completing a training program , patients perform their own blood testing ( typically , using a finger-stick blood analyzer ) , have dosage adjustments guided by a st and ard protocol , and forward test results , dosing and other information to the provider . Studies have suggested that PST can improve the quality of AC and perhaps lower TE and bleed rates . The purpose of Department of Veterans Affairs ( VA ) Cooperative Studies Program ( CSP ) # 481 , “ The Home INR Study ” ( THINRS ) is to compare AC management with frequent PST using a home monitoring device to high quality AC management ( HQACM ) implemented by an ACS with conventional monitoring of prothrombin time by international normalized ratio ( INR ) on major health outcomes . PST in THINRS involves use of an INR monitoring device that is FDA approved for home use . Study design : Sites are VA Medical Centers where the ACS has an active roster of more than 400 patients . THINRS includes patients with atrial fibrillation ( AF ) and /or mechanical heart valve ( MHV ) expected to be anticoagulated indefinitely . THINRS has two parts . In Part 1 , c and i date s for PST are evaluated for 2 to 4 weeks for their ability to use home monitoring devices . In Part 2 , individuals capable of performing PST are r and omized to ( 1 ) HQACM with testing every 4 weeks and as indicated for out of range values , medication/ clinical changes , or ( 2 ) PST with testing every week and as indicated for out of range values , medication/ clinical changes . The primary outcome measure is event rates , defined as the percent of patients who have a stroke , major bleed , or die . Secondary outcomes include total time in range ( TTR ) , other events ( myocardial infa rct ion ( MI ) , non-stroke TE , minor bleeds ) , competence and compliance with PST , satisfaction with AC , AC associated quality of life ( QOL ) , and cost-effectiveness . To assess the effect of PST frequency on TTR and other outcomes , at selected sites patients r and omized to perform PST are assigned one of three test frequencies ( weekly , twice weekly , or once every four weeks ) BACKGROUND Increased frequency of prothrombin time testing , facilitated by patient self-testing ( PST ) of the International Normalized Ratio ( INR ) can improve the clinical outcomes of oral anticoagulation therapy ( OAT ) . However , oversight of this type of management is often difficult and time-consuming for healthcare professionals . This study reports the first r and omized controlled trial of an automated direct-to-patient expert system , enabling remote and effective management of patients on OAT . METHODS A prospect i ve , r and omized controlled cross-over study was performed to test the hypothesis that supervised PST using an internet-based , direct-to-patient expert system could provide improved anticoagulation control as compared with that provided by an anticoagulation management service ( AMS ) . During the 6 months of supervised PST , patients measured their INR at home using a portable meter and entered this result , along with other information , onto the internet web page . Patients received instant feedback from the system as to what dose to take and when the next test was due . During the routine care arm , patients attended the AMS at least every 4 - 6 weeks and were dosed by the anticoagulation pharmacist or physician . The primary outcome variable was the difference in the time in therapeutic range ( TTR ) between both arms . RESULTS One hundred and sixty-two patients were enrolled ( male 61.6 % , mean age 58.7 years ) , and 132 patients ( 81.5 % ) completed both arms .  TTR was significantly higher during PST management than during AMS management ( median TTR 74 % vs 58.6 % ; z=5.67 , P < 0.001 ) . CONCLUSIONS The use of an internet-based , direct-to-patient expert system for the management of PST improves the control of OAT as compared with AMS management Oral anticoagulant therapy requires frequent laboratory controls of its intensity to assure therapeutic efficacy and to prevent potentially life threatening adverse events . It is generally assumed , that increasing the frequency of testing would lead to a better control of anticoagulation . We tested this hypothesis in a prospect i ve controlled trial comparing weekly self-testing and self-dosing ( self management ) with the st and ard-management of these patients in an anticoagulation clinic . Only patients with stable anticoagulation were included into the study . We recorded 2733 weekly determinations of the intensity of anticoagulation ( INR ) in 49 patients on self-testing and self-dosing and 539 determinations of the INR in 53 patients on st and ard-management .  Two intensities of anticoagulation were used in each group : a target INR of 3.5 for patients with artificial heart valves ( target range : 2.5 - 4.5 ) and a target INR 2.5 ( target range : 2.0 - 3.0 ) for patients with atrial fibrillation or venous thromboembolism . The deviation from the target INR , the fraction of INR determinations within the preset therapeutic range and the difference between the target INR and the actually achieved mean INR were the three major endpoints of the study . The mean deviation from the target INR was smaller in the groups of patients on self-management compared to the patients on st and ard-management . Individual deviations were significantly ( p < 0.0001 ) dependent on the type of management in interaction with the treatment intensity in a general linear model . Patients on weekly self-testing and self-dosing  had more INR values within the therapeutic range than patients on st and ard-management ( 86.2 % vs. 80.1 % at INR range 2.5 - 4.5 ; 82.2 vs. 68.9 at INR range 2.0 - 3.0 ) . The achieved mean INR was almost identical with the target INR in the patients on self-management but was significantly ( p < 0.005 ) below the target INR in the high intensity anticoagulation group on st and ard-management ( target INR:3.5 ; achieved mean INR : 3.19 ; CI 0.95 : 3.05 - 3.34 ) . Our data show , that weekly self-testing and self-dosing leads to a better control of anticoagulation than st and ard treatment in an anticoagulation clinic OBJECTIVE To investigate the effectiveness of patient self-management ( PSM ) of anticoagulation using warfarin in a typical primary care site in Canada and to determine the feasibility of conducting a future large-scale trial in this setting . DESIGN An 8-month pragmatic open-label r and omized crossover trial . SETTING A typical Canadian primary care practice in British Columbia . INTERVENTION Patients were r and omized to PSM or physician management for 4 months , after which allocation was reversed . The PSM group members were instructed to monitor their serum international normalized ratio ( INR ) at community laboratories and to adjust their warfarin doses independently using provided nomograms . Education on warfarin dose adjustment was limited to a single 15-minute office visit . MAIN OUTCOME MEASURES The primary outcome was the proportion of INR values in the therapeutic range among participants . Feasibility outcomes included proportion of eligible patients consenting , patients ' preference of management strategy , patients ' satisfaction , and visits or phone communication with physicians regarding dose adjustment . Safety outcomes included bleeding or thromboembolic events . RESULTS Eleven patients completed the trial , contributing 99 patient-months of monitoring and providing 122 INR measures . The mean proportion of INR values in therapeutic range among subjects in the PSM and physician-management groups was 82 % and 80 % , respectively ( P = .82 ) . The improvement in patient satisfaction with PSM was not significant . Ten of the 11 patients preferred PSM to physician management and elected to continue with this strategy after study completion ( P = .001 ) . No calls or visits were made to the physician regarding dose adjustment during the PSM period . There were no episodes of major bleeding or thromboembolic events . CONCLUSION Patient self-management was not demonstrated to be superior to st and ard care , but was easily implemented and was the method preferred by patients . Our feasibility outcomes justify a larger trial and suggest that subject recruitment and protocol adherence would not pose barriers for such a study . Trial registration number NCT00925028 ( Clinical Trials.gov ) Background —The Early Self Controlled Anticoagulation Trial ( ESCAT I ) showed that anticoagulation self-management after mechanical heart valve replacement decreased complication rates by maintaining INR levels closer to the target range than International Normalized Ratio ( INR ) home doctor management . The therapeutic range for the INR in that study was between 2.5 and 4.5 for all positions of prosthetic valves . ESCAT II should find out whether lowering the target range for INR self-management would further reduce complication rates . Methods —ESCAT II is a prospect i ve controlled r and omized ( valves : St. Jude Medical St and ard or Medtronic Hall , treatment : conventional/low-dose ) multicenter study with 3 300 patients . We present interim results of 1 818 patients . 908 were categorized as having a low-dose target range , which was INR 1.8 to 2.8 for prostheses in aortic position and 2.5 to 3.5 for prostheses in mitral position or in combined valve replacement . The control group ( conventional group ) with 910 patients aim ed at an INR of 2.5 to 4.5 for all valve positions . Results —In the conventional group , 74 % of INR values measured were within the therapeutic range . In the low-dose group , 72 % of the values were within that range . The linearized thromboembolism rate ( % per patient year ) was 0.21 % for both groups . The bleeding complication rate was 0.56 % in the low-dose regimen group versus 0.91 % in the conventional group . Conclusions —Early onset INR self-management under oral anticoagulation after mechanical heart valve replacement enables patients to keep within a lower and smaller INR target range . The reduced anticoagulation level result ed in fewer grade III bleeding complications without increasing thromboembolic event rates Background Oral anticoagulation monitoring has traditionally taken place in secondary care because of the need for a laboratory blood test , the international normalised ratio ( INR ) . The development of reliable near patient testing ( NPT ) systems for INR estimation has facilitated devolution of testing to primary care . Patient self-management is a logical progression from the primary care model . This study will be the first to r and omise non-selected patients in primary care , to either self-management or st and ard care . Method The study was a multi-centred r and omised controlled trial with patients from 49 general practice s recruited . Those suitable for inclusion were aged 18 or over , with a long term indication for oral anticoagulation , who had taken warfarin for at least six months . Patients r and omised to the intervention arm attended at least two training sessions which were practice -based , 1 week apart . Each patient was assessed on their capability to undertake self management . If considered capable , they were given a near patient INR testing monitor , test strips and quality control material for home testing . Patients managed their own anticoagulation for a period of 12 months and performed their INR test every 2 weeks . Control patients continued with their pre- study care either attending hospital or practice based anticoagulant clinics . Discussion The methodology used in this trial will overcome concerns from previous trials of selection bias and relevance to the UK health service . The study will give a clearer underst and ing of the benefits of self-management in terms of clinical and cost effectiveness and patient preference Abstract Background : R and omized control trials and observational studies show high- quality warfarin therapy leads to safe and effective stroke prophylaxis . In usual community practice , patient , physician and health care system factors are barriers to optimal anticoagulation . We examined the predictive relationship between inpatient and outpatient INR values in chronic non-valvular atrial fibrillation ( AF ) patients hospitalized for ischemic stroke ( S ) , bleed ( B ) and control events ( C ) in usual community practice . Methods : This nested case-control analysis identified AF patients hospitalized for S , B and C using medical and pharmacy cl aims spanning 4.5 years ( ‘ 98–‘03 ) and validating diagnosis with chart abstract ion . AF was defined as 2 medical cl aims for AF ≥ 42 days apart with a related prescription cl aim for warfarin . INRs from both outpatient and inpatient setting s were used to yield a continuous history of coagulation status . Time-in-therapeutic-range ( TTR ) was calculated by Rosendaal ’s linear interpolation method . Correlation of inpatient and prognostic utility of last outpatient INRs was tested with S or B hospitalizations using univariate and multivariate logistic regression . Results : Overall , 614 hospitalizations ( means : age 73.9 , CHADS2 = 3.24 ; 52 % male ) included S ( n = 98 ) , B ( n = 101 ) and C ( n = 415 ) events . Average TTR was 28.6 % ( 49.4 % at INR < 2.0 , 21.9 % at INR > 3.0 ) . First INR on admission ( INR < 2.0 or > 3.0 ) was associated with S and B hospitalizations ( OR-adjusted [ 95%CI ] , 1.68 [ 1.04–2.73 ] and 1.72 [ 1.02–2.90 ] ) , respectively . Last outpatient INR < 2.0 was not associated with S ( OR-adjusted [ 95%CI ] , 1.12 [ 0.77–1.81 ] ) , and INR > 3.0 was not associated with B ( OR-adjusted [ 95%CI ] , 1.25 [ 0.67–2.32 ] ) . Last outpatient INR measurement occurred at 28 , 22 and 24 days ( median ; S , B & C , respectively ) before hospitalization . Conclusion : Patients were observed within therapeutic range less than 30 % of their time on warfarin . While inpatient INRs were clearly associated with both ischemic stroke and bleed events , last outpatient INR before event was not predictive BACKGROUND The anticoagulant activity of warfarin sodium is monitored by the prothrombin time ( PT ) . The introduction of a portable PT monitor has raised the possibility that patients could reduce the inconvenience of anticoagulant therapy by measuring their PT at home . We performed this study to determine the feasibility and accuracy of home use of the portable PT monitor . METHODS A prospect i ve cohort study was performed in consecutive eligible patients who required long-term anticoagulant therapy .  Patients performed multiple measurements of their PT at home by means of the portable monitor and at their usual laboratory within a 4-hour interval . The accuracy of the portable monitor was evaluated by two criteria for agreement . St and ard agreement was achieved if the portable monitor and laboratory results were both either within or outside the patient 's targeted therapeutic range or if the two results were within 0.4 international normalized ratio units of each other . Exp and ed agreement was achieved if both the portable monitor and laboratory results were within + /- 0.4 international normalized ratio units of the targeted therapeutic range . RESULTS Forty patients ( 19 men and 21 women , aged 25 to 74 years ) were followed up for 6 to 24 months by means of the portable PT monitor . The mean level of agreement achieved per patient was 83 % ( 95 % confidence interval , 79 % to 87 % ) by the st and ard criteria and 96 % ( 95 % confidence interval , 94 % to 98 % ) by the exp and ed criteria . Twenty-seven patients ( 68 % ) and 39 patients ( 98 % ) achieved more than 80 % agreement by the st and ard and the exp and ed criteria , respectively . Question naire results revealed that 97 % of the patients preferred using the portable monitor to measure their PT . CONCLUSIONS Patients receiving long-term anticoagulant therapy achieved a high rate of clinical ly important agreement between self- measurements of the PT with the use of a portable monitor and laboratory PT results . Patients strongly preferred using the portable monitor to measure their PT levels . The use of the portable monitor as the primary method for measuring the PT can be recommended in selected patients receiving long-term anticoagulant treatment Several studies suggest that patient self‐management ( PSM ) may improve the quality of oral anticoagulation therapy as measured by time spent within the international normalised ratio ( INR ) target range . We performed a prospect i ve r and omised control trial to determine whether the improvement in quality of treatment afforded by PSM is greater than that achieved by patient self‐testing ( PST ) alone . A total of 104 of 800 eligible patients aged 22–88 years ( median = 59·8 ) , attending our hospital anticoagulant clinic and receiving long‐term warfarin for > 8 months agreed to participate . Patients were r and omised to PSM ( n = 55 ) or PST ( n = 49 ) . Both groups measured their INR using the CoaguChek S every 2 weeks or more frequently if required , for a period of 6 months . Seventy‐seven of 104 ( 74 % ) patients completed the study ( PSM = 41 and PST = 36 ) . The ‘ drop out ’ rates for both groups were similar . There was no significant difference between the percentage time in target therapeutic range  for PSM ( 69·9 % ) and PST ( 71·8 % ) . Both groups combined showed a significant improvement over the previous 6 months ( 71·0 % vs. 62·5 % ; P = 0·04 ) . Changes in time within the therapeutic range in individual patients ( + 5·86 ) also showed a significant difference . The quality of warfarin control  in both PST and PSM may be superior to that achieved by conventional management in a specialised hospital anticoagulation clinic An ageing population and the continuing expansion of clinical indications for coumadin therapy have increased pressure on hospital anticoagulant clinics . One solution is patient self‐testing ( PST ) of the international normalized ratio ( INR ) using capillary blood sample s on point‐of‐care coagulation monitors at home . We conducted a prospect i ve study to determine whether patients can achieve accurate INR values through PST , using the CoaguChek S ( Roche Diagnostics , Lewes , UK ) . The main outcome measurements were : comparability of INR values obtained by PST and the hospital laboratory , patient acceptability as assessed by a question naire and anticoagulant control . Eighty‐four patients [ 53 men , 31 women ; median age 59 years ( range 26–83 ) ] , receiving long‐term oral anticoagulation ( warfarin ) , were recruited from our Anticoagulation Clinic . Patients were r and omized to weekly self‐testing or continuing 4‐weekly hospital laboratory monitoring of INR . Comparison of INRs ( n = 234 ) showed no significant differences between the CoaguChek ( median INR 3·02 ) and laboratory testing ( median INR 3·07 ) . There was excellent correlation between the two methods ( r = 0·95 ) , with 85 % of CoaguChek results within 0·5 INR units of the laboratory method . On four occasions , differences of > 1 unit INR were obtained , but in each case the patient 's anticoagulation was unstable ( INR > 4·5 by both methods ) and the differences in INR would not have altered patient management . 87 % of patients found self‐testing straightforward , 87 % were confident in the result they obtained and 77 % preferred self‐testing . We conclude that PST is a reliable alternative to hospital clinic attendance and is acceptable to the majority of suitably trained patients OBJECTIVES To evaluate the effect of a shared care programme ( SCP ) , defined as a scheme based on shared responsibility , enhanced information exchange , continues medical education and explicit clinical guidelines , between general practitioners ( GPs ) and a hospital outpatient clinic ( HOC ) , on  oral anticoagulant therapy ( OAT ) . DESIGN The study was a 2-year prospect i ve , r and omized , controlled trial , preceded by a 1-year period of observation . SETTING The HOC , GPs , and OAT patients in the admission area of Aarhus University Hospital , Aarhus County , Denmark , covering 310 300 inhabitants . SUBJECTS A total of 207 GPs , including their enlisted patients on OAT , were invited , and 61.4 % accepted participation . They were r and omized into an intervention group [ group-INT : 64 GPs and 453 patients ( 170 patients on  OAT throughout the study period , i.e. full follow-up ) ] , and a control group [ group-CON : 63 GPs and 422 patients ( 173 with full follow-up ) ] . The remaining 80 GPs served as a nonresponder group ( group-NON ) of 485 patients ( 184 with full follow-up ) . MAIN OUTCOME MEASURE Therapeutic control of OAT in terms of time spent by the patients within the therapeutic interval ( TI ) of an international normalized ratio ( INR ) between 2.0 and 3.5 . RESULTS The groups did not differ significantly with regard to age , sex , OAT indication , anticoagulant drug used , or the therapeutic control at baseline . In a comparison based on intention-to-treat principles , the therapeutic control increased statistical significance amongst patients with full follow-up in group-INT compared with group-CON ( median time within TI : group INT = 86.6 % vs. 80.5 % , P = 0.007 ) . CONCLUSION An SCP of anticoagulant management is effective in reducing patient time outside the therapeutic INR interval in OAT patients r and omly assigned to an SCP , as compared with a control group Background and objective Internet-based disease management programs have the potential to improve patient care . The objective of this study was to determine whether an interactive , internet-based system enabling supervised , patient self-management of oral anticoagulant therapy provided management comparable to an established anticoagulation clinic . Patients / methods Sixty patients receiving chronic oral anticoagulant therapy who had access to the internet and a printer , were enrolled into this prospect i ve , single-group , before-after study from a single clinic and managed between March 2002 and January 2003 . Patients learned how to use a home prothrombin time monitor and how to access the system through the internet . Patients used the system for six months , with daily review by the supervising physician . The primary outcome variable was the difference in time in therapeutic range prior to and following introduction of internet-supervised patient self-management . Results The mean time in therapeutic range increased from 63 % in the anticoagulation clinic ( control period ) to 74.4 % during internet-supervised patient self-management ( study period ) . The mean difference score between control and study periods was 11.4 % ( P = 0.004 , 95 % confidence interval 5.5–17.3 % ) . There were no hemorrhagic or thromboembolic complications . Conclusions This novel approach of internet-supervised patient self-management improved time in therapeutic range compared to an anticoagulation clinic . This is the first demonstration of an internet-based expert system enabling remote and effective management of patients on oral anticoagulants . Expert systems may be applicable for management of other chronic diseases AIMS The Warfarin Self-Management Anticoagulation Research Trial ( Warfarin SMART ) was design ed to determine whether  patients self-managing warfarin ( PSM )  using the CoaguChek device and a dosing algorithm developed for the trial could keep the INR ( International Normalised Ratio ) test in target range at least as often as patients managed by usual care by the family doctor or hospital clinic . METHODS AND RESULTS 310 patients were r and omly assigned to PSM or usual care . The PSM group was trained to perform home INR testing and warfarin dosing using a vali date d ColourChart algorithm . The primary endpoint was the proportion of times over 12 months that a monthly , blinded " outcome INR test " , measured in a central laboratory , was outside the patient 's target therapeutic range . The rate of out-of-range outcome INRs was lower in PSM , and non-inferior to the usual care group ( PSM : 36 % vs. usual care : 41 % , P<0.001 for non-inferiority ; P=0.08 for superiority in closed-loop testing ) . The deviations from the patient 's midpoint of target INR range ( P=0.02 ) and number of extreme INRs ( P=0.03 ) were significantly less in the PSM group than the usual-care group . There was no significant difference between groups in rates of bleeding or thrombotic adverse events . CONCLUSION Patient self-management performed at least as well as usual care in maintaining the INR within the target range , without any safety concerns . This treatment modality for the long-term use of warfarin has the potential to change current local and international practice BACKGROUND Although prosthetic valves are durable and easy to implant , the need for lifetime warfarin-based anticoagulation restricts their exclusive usage . We investigated if anticoagulation self-management improves outcome in a single-center series . METHODS Between 1994 and 1998 , 765 patients with prosthetic valve replacements were prospect ively enrolled and r and omized to receive conventional anticoagulation management by their primary physician ( group 1 , n = 295 ) or to pursue anticoagulation self-management ( group 2 , n = 470 ) . A study head office was implemented to coordinate and monitor  anticoagulation protocol s ,  international normalized ratios ( INR ) , and  adverse events . Patients were instructed on how to obtain and test their own blood sample s and to adjust warfarin dosages according to the measured INR ( target range , 2.5 to 4 ) . RESULTS Mean INR values were slightly yet significantly smaller in group 1 than in group 2 ( 2.8 + /- 0.7 vs 3.0 + /- .6 , p < 0.001 ) . Moreover , INR values of patients with conventional INR management were frequently measured outside the INR target range , whereas those with anticoagulation self-management mostly remained within the range ( 35 % vs 21 % , p < 0.001 ) . In addition , the scatter of INR values was smaller if self-managed . Freedom from thromboembolism at 3 , 12 , and 24 months , respectively , was 99 % , 95 % , and 91 % in group 1 compared with 99 % , 98 % , and 96 % in group 2 ( p = 0.008 ) . Bleeding events were similar in both groups . Time-related multivariate analysis identified INR self-management and higher INR as independent predictors for better outcome . CONCLUSIONS Anticoagulation self-management can improve INR profiles up to 2 years after prosthetic valve replacement and reduce adverse events . Current indications of prosthetic rather than biologic valve implantations may be extended if the benefit of INR self-management is shown by future studies with longer follow-up It has been observed that elderly patients with nonvalvular atrial fibrillation ( NVAF ) benefit from st and ard [ an international normalised ratio ( INR ) goal of 2.0 - 3.0 ] oral anticoagulant treatment ( OAT ) . The hypothesis that lower-intensity anticoagulation therapy can offset the higher bleeding risk in this population has never been tested in an ' ad hoc ' clinical trial . Patients over 75 years of age with NVAF were r and omised to receive warfarin to maintain the INR at 1.8 ( range 1.5 - 2.0 ) or at a st and ard target of 2.5 ( range 2.0 - 3.0 ) . There were 135 patients in the low-intensity and 132 in the st and ard-intensity groups . During a mean follow-up lasting 5.1 years , 59 primary outcome events ( thromboembolism and major haemorrhage ) were recorded , 24 ( 3.5 per 100 patient-years ) in the low-intensity group and 35 ( 5.0 per 100 patient-years ) in the st and ard-intensity group ( HR=0.7 , 95 % CI 0.4 - 1.1 , p=0.1 ) . The reduction in the primary endpoint was mainly due to a diminution in major bleedings ( 1.9 vs. 3.0 per 100 patient-years ; HR=0.6 , 95 % CI 0.3 - 1.2 , p=0.1 ) . The median achieved INR value was 1.86 in the low-intensity and 2.24 in the st and ard-intensity group ( p<0.001 ) . The frequency of INR testing was 26.1 + /- 13.5 vs. 24.3 + /- 11.6 days , p<0.0001 ) . In this exploratory study we observed a low rate of stroke and major bleeding in elderly patients ( > 75 ) being managed in an anticoagulation clinic for primary stroke prevention with low-intensity anticoagulation ( INR 1.5 - 2.0 ) . However , further trials are needed to confirm the hypothesis generated by the present study Background : The increase in numbers of patients receiving warfarin treatment has led to the development of alternative models of service delivery for oral anticoagulant monitoring . Patient self management for oral anticoagulation is a model new to the UK . This r and omised trial was the first to compare routine primary care management of oral anticoagulation with patient self management . Aim : To test whether patient self management is as safe , in terms of clinical effectiveness , as primary care management within the UK , as assessed by therapeutic international normalised ratio ( INR ) control . Method : Patients receiving warfarin from six general practice s who satisfied study entry criteria were eligible to enter the study . Eligible patients were r and omised to either intervention ( patient self management ) or control ( routine primary care management ) for six months . The intervention comprised two training sessions of one to two hours duration . Patients were allowed to undertake patient self management on successful completion of training . INR testing was undertaken using a Coaguchek device and regular internal/external quality control tests were performed . Patients were advised to perform INR tests every two weeks , or weekly if a dose adjustment was made . Dosage adjustment was undertaken using a simple dosing algorithm . Results : Seventy eight of 206 ( 38 % ) patients were eligible for inclusion and , of these , 35 ( 45 % ) declined involvement or withdrew from the study . Altogether , 23 intervention and 26 control patients entered the study . There were no significant differences in INR control ( per cent time in range : intervention , 74 % ; control , 77 % ) . There were no serious adverse events in the intervention group , with one fatal retroperitoneal haemorrhage in the control group . Costs of patient self management were significantly greater than for routine care ( £ 90 v £ 425/patient/year ) . Conclusion : These are the first UK data to demonstrate that patient self management is as safe as primary care management for a selected population . Further studies are needed to eluci date whether this model of care is suitable for a larger population
Experts , however , have commented that there may be under-utilization of OAT due to patient factors , physician factors , or regional practice variations and that sub-optimal patient management may also occur .
These models are not suitable for all patients and require the identification and education of suitable c and i date s. Potential advantages of POC devices include improved convenience to patients , better treatment compliance and satisfaction , more frequent monitoring and fewer thromboembolic and hemorrhagic complications .
Potential disadvantages of the device include the tendency to underestimate high INR values and overestimate low INR values , low thromboplastin sensitivity , inability to calculate a mean normal PT , and errors in INR determination in patients with antiphospholipid antibodies with certain instruments .
Although treatment satisfaction and quality of life ( QoL ) may improve with POC INR monitoring , some patients may experience increased anxiety or preoccupation with their disease with these strategies .
The majority of studies reported favourable impacts of POC INR monitoring on QoL and found better treatment satisfaction with POC monitoring .
UNLABELLED SUBJECT OF THE EVIDENCE -BASED ANALYSIS : The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care ( POC ) international normalized ratio ( INR ) monitoring devices for patients on long-term oral anticoagulation therapy ( OAT ) .
CLINICAL NEED TARGET POPULATION AND CONDITION Long-term OAT is typically required by patients with mechanical heart valves , chronic atrial fibrillation , venous thromboembolism , myocardial infa rct ion , stroke , and /or peripheral arterial occlusion .
It is estimated that approximately 1 % of the population receives anticoagulation treatment and , by applying this value to Ontario , there are an estimated 132,000 patients on OAT in the province , a figure that is expected to increase with the aging population .
Patients on OAT  are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range .
This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses .
Optimal INR scores depend on the underlying indication for treatment and patient level characteristics , but for most patients the therapeutic range is an INR score of between 2.0 and 3.0 .
There is currently no population -based Ontario data to permit the assessment of patient care , but recent systematic review s have estimated that less that 50 % of patients receive OAT on a routine basis and that patients are in the therapeutic range only 64 % of the time .
OVERVIEW OF POC INR DEVICES POC INR devices offer an alternative to laboratory-based testing and venipuncture , enabling INR determination from a fingerstick sample of whole blood .
Independent evaluations have shown POC devices to have an acceptable level of precision .
They permit INR results to be determined immediately , allowing for more rapid medication adjustments .
POC devices can be used in a variety of setting s including physician offices , ACCs , long-term care facilities , pharmacies , or by the patients themselves through self-testing ( PST ) or self-management ( PSM ) techniques .
With PST , patients measure their INR values and then contact their physician for instructions on dose adjustment , whereas with PSM , patients adjust the medication themselves based on pre-set algorithms .
EffectivenessDoes POC INR monitoring improve clinical outcomes in various setting s compared to st and ard laboratory-based testing?Does POC INR monitoring impact patient satisfaction , QoL , compliance , acceptability , convenience compared to st and ard laboratory-based INR determination ?
Cost-effectivenessWhat is the cost-effectiveness of POC INR monitoring devices in various setting s compared to st and ard laboratory-based INR determination ?
ANTICOAGULATION CONTROL Anticoagulation control is measured by the percentage of time INR is within the therapeutic range or by the percentage of INR values in the therapeutic range .