Specialized anticoagulation clinic care

Six systematic reviews were identified that compared specialized anticoagulation services with UC.^33–38 Results are summarized in Table 2 and Appendix 3.

Table 2

Summary of Results for Specialized Clinic Care versus Usual Care.

In 2011, the US Department of Veterans Affairs published a systematic review comparing specialized anticoagulation clinics with UC for long-term anticoagulation.³³ UC was defined as non-specialized clinics, such as primary care clinics or physician offices. Included studies were limited to those involving an adult, outpatient population receiving chronic anticoagulation therapy. Non-English articles, or studies dealing with inpatients, pediatric populations, or short-term anticoagulation (less than three months) were excluded. The review identified 11 articles (three RCTs and eight cohort studies) that met all inclusion criteria. RCTs and cohort studies were analyzed separately.

The follow-up interval in the RCTs was three months in one study and up to two years in another. The follow-up time for the third RCT was not reported. Pooled analysis of the three RCTs indicated no difference between anticoagulation clinics and UC in rates of mortality (RR 0.81, 95% CI 0.25 to 2.58), major thromboembolic events (RR 1.05, 95% CI 0.36 to 3.12), and major bleeding events (RR 1.29, 95% CI 0.59 to 2.81). The pooled weighted mean TTR was higher for patients treated in an anticoagulation clinic (59.9% versus 56.3% for UC) for a weighted mean difference of 3.6% (range of mean differences, 3.3% to 5%, 95% CI not reported).

Results from cohort studies were not pooled. One included study reported mortality and found no significant difference between clinic and usual care. Four included studies reported major thromboembolic events. One reported a significantly higher incidence with UC, one reported a statistically significant higher incidence with clinic care, and two did not report P-values. The incidence of major bleeding was reported in five studies. One found a significantly higher rate of bleeding incidents with UC, and one found no statistically significant difference. The remaining studies did not report significance. Four studies reported TTR. The pooled weighted mean of TTR was higher with clinic care (63.5% versus 53.5%) for a weighted mean difference of 10% (range of mean differences, 4.3% to 26%, 95% CI not reported). Three included observational studies reported hospital admissions or emergency department visits. One found no difference between clinic and UC groups, while two found significantly fewer anticoagulation-related hospitalizations with clinic care.

A 2010 systematic review and meta-analysis by Saokaew et al.³⁴ included 24 studies (five RCTs, 19 non-randomized trials) comparing UC with warfarin therapy in which a pharmacist participated. UC was defined as a control group comprising health care professionals other than pharmacists as service providers. In 19 studies, this was a physician. Details of UC were not reported for the other five studies. Results of pooled analysis were reported separately for RCTs and non-randomized studies.

Care in which a pharmacist participated was found to reduce the risk of bleeding events in RCTs (RR 0.51, 95% CI 0.28 to 0.94) and non-randomized (RR 0.71, 95% CI 0.52 to 0.96) studies. When only major bleeding events (based on individual study definitions) were considered, no significant difference was observed in RCTs (RR 0.64, 95% CI 0.18 to 2.36, P = 0.507). A reduction in major bleeding events with pharmacist care was observed in pooled analysis of non-randomized studies (RR 0.49, 95% CI 0.26 to 0.93, P = 0.030). Similarly, RCTs found no statistically significant difference in total thromboembolic events in pharmacist-managed care compared with UC (RR 0.79, 95% CI 0.33 to 1.93, P = 0.610), while a statistically significant reduction was observed with pharmacist-managed care in non-randomized studies (0.37, 95% CI 0.26 to 0.53, P < 0.001). No statistically significant difference in mortality was observed with pharmacist-managed care compared with UC in either RCTs (RR 0.93, 95% CI 0.41 to 2.13, P = 0.867) or non-randomized studies (RR 0.85, 95% CI 0.37 to 1.98, P = 0.711).

In a 2009 systematic review and meta-analysis, Cios et al.³⁵ evaluated the impact of study setting on INR control in US studies. For the purpose of evaluating the impact of study-level factors on warfarin control, RCTs were considered separately from observational studies. The analysis included 24 studies with 43 study groups performed in an anticoagulation clinic (the study was not an RCT and was performed in a clinic, or the stated role of clinicians in patient care was limited to anticoagulation management) or community practice (the study could not be classified as anticoagulation clinic or RCT). TTR across all included studies was 57% (95% CI 55% to 59%). Subgroup analysis showed that the overall TTR in the anticoagulation clinic setting was 64% (95% CI 61% to 67%), while in community practice, TTR was 51% (95% CI 48% to 54%). After meta-regression analysis using a multiple-linear, mixed-method model controlling for study-level factors, the adjusted difference (–13, 95% CI –18.1 to –7.9) was statistically significant (P < 0.001). In post-hoc analyses, Canadian warfarin studies were included, with similar results. With Canadian studies included, clinic TTR was 65% (95% CI 61% to 69%) and community practice TTR was 53% (95% CI 50% to 56%), a statistically significant adjusted difference (–11.3, 95% CI –16.2 to –6.3, P < 0.001). Results from Canadian studies were not reported separately.

A systematic review and meta-analysis performed by Baker et al.³⁶ in 2009 examined the effect of warfarin management setting on TTR in patients with atrial fibrillation. The setting was defined as an anticoagulation clinic if the study took place in a clinic or the stated role of study clinicians was limited to anticoagulation management. All others were classified as community practice. To be included in the meta-analysis, studies had to contain at least one warfarin-treated group with a minimum of 25 patients who had INR monitoring for at least three weeks. No included studies were RCTs. A total of eight studies (four anticoagulation clinic and six community practice; two studies examined both) with 13 study groups (four anticoagulation clinic and nine community practice) were included. With anticoagulation clinic-based warfarin dosing, patients had an average TTR of 63% (95% CI 58% to 68%) compared with an average TTR of 51% (95% CI 47% to 55%) in community practice. Compared with anticoagulation clinics, patients in community practice spent 11% less time in range (95% CI 2% to 20%, n = six studies with nine groups), based on meta-regression analysis. Additionally, five included trials reported the proportion of eligible atrial fibrillation patients receiving warfarin. A definition of eligibility was not provided. The proportion of eligible patients receiving warfarin was higher in the clinic setting (53%, 95% CI 38% to 72%) compared with community-based dosing (47%, 95% CI 41% to 54%), but the significance of this result was not discussed.

In 2008, Dolan et al.³⁷ published a systematic review and meta-analysis examining the effect of various factors, including management setting, on TTR. A total of 36 studies met inclusion criteria, of which 22 dealt exclusively with patients with AF and had at least one treatment group given oral anticoagulation treatment with a target INR range of 2.0 to 3.0. The remaining 14 studies were conducted in patients with mixed indications and were not included in the primary analysis. These 14 studies were used to conduct sensitivity analysis. Among the AF studies, 18 study groups were judged to have received anticoagulation care in an organized setting (specialized care, including anticoagulation clinics) and 10 study groups were categorized as UC (care delivered in non-specialist settings, including family practice). Patients receiving organized care had a higher TTR (63.6%, 95% CI 61.3% to 65.9%) compared with those receiving UC (52.3%, 95% CI 42.1% to 62.4%). This difference of 11.3% was found to be statistically significant (95% CI 0.1% to 21.7%).

A 2006 systematic review by van Walraven et al.³⁸ examined the effect of study setting on anticoagulation control. Studies were included if they contained data measuring anticoagulation control in at least one patient group. A total of 67 studies including 123 study groups were classified as being based in an anticoagulation clinic (the authors stated the study was set in a clinic, or the methods stated that the role of study physicians were limited to INR control), a randomized controlled trial, or as community-based practice (all other studies). Patients treated in randomized controlled trials had a mean TTR of 66.4% (95% CI 59.4% to 73.3%), clinic patients had a mean TTR of 65.6% (95% CI 63.7% to 67.7%), and those treated in a community practice setting had a mean TTR of 56.7% (95% CI 51.5% to 62.0%). There was no significant difference in TTR between the RCT and clinic groups (−3.9%, 95% CI –10.7 to 2.9). However, a decrease in TTR of 12.2% (95% CI 4.8% to 19.5%) was observed in patients treated by their community physicians, compared with RCTs. Community practices had statistically significant lower rates of INR control compared with both anticoagulation clinics and RCTs.

In addition to the included systematic reviews, five studies were identified that compared specialized anticoagulation clinics with UC, which were not included in an included systematic review. The results of these four studies are summarized in Table 2 and Appendix 4.

One cohort study¹⁵ compared patients referred to a nurse-managed anticoagulation clinic (n = 131) with patients managed by physicians (n = 2,266) for long-term anticoagulation therapy (not defined). POC testing was not used. The rate of emergency room (ER) visits was lower for patients receiving care in the nurse-managed clinic compared with usual physician care (1.5% versus 10.9%). Similarly, hospitalization rate was lower with clinic care (2.3% versus 12.8%). Statistical analysis was not done on these figures, but cost savings due to fewer ER visits or hospitalizations were significantly lower in the clinic model (P = 0.0006 and P = 0.0004, respectively).

One retrospective medical record review¹⁶ compared patients receiving usual physician care before and after transfer with a pharmacist-managed anticoagulation clinic using POC INR testing (n = 64). All patients had been established at the clinic for at least one year. TTR was not reported, but the percentage of INR tests within the therapeutic range was reported instead. The number of INR measurements within the therapeutic range was higher after transfer to the pharmacist-managed clinic (81.1% versus 71.1%, P < 0.0001). The estimated variance in therapeutic INR rates was significantly higher for usual physician care (365.7 versus 185.2, P = 0.004).

One retrospective cohort study¹⁷ compared 175 patients receiving usual physician care with the same number managed by a pharmacist-administered anticoagulation service for at least two months. TTR, calculated using the linear interpolation method, was higher in pharmacist-managed care compared with UC (73.7% versus 61.3%, P < 0.0001). The number of ER visits (58 versus 134, P < 0.00001) and hospital admissions (three versus 14, P < 0.00001) were significantly lower with clinic care. Similarly, the anticoagulation-related adverse event rate was lower with clinic care (5.1% versus 15.4%, P < 0.0001) but the nature of these events (thrombosis, hemorrhage, etc.) was not described.

One retrospective chart review¹⁸ compared UC by the patient’s primary care provider with either pharmacist- or nurse-managed anticoagulation services. TTR was lowest in patients treated in the primary care model compared with nurse- or pharmacist-managed care (57.4% versus 71.8% versus 83.6% for primary, nurse, and pharmacist care, respectively; P < 0.05 between all models). Hospitalization rate was higher for primary care (13.9 hospitalizations per 100 patient-years) and nurse-managed care (12.3 per 100 patient-years) compared with pharmacist-managed care (5.4 per 100 patient-years, P < 0.05). Similarly, the rate of emergency department visits (expressed as number per 100 patient-years) was higher for primary care (5.6) and nurse-managed clinics (5.6) compared with pharmacist-managed care (1.2, P < 0.05). There was no significant difference in hospitalization or ER visit rate between the nurse-managed model and UC.

A 2008 retrospective study compared the quality of anticoagulation care before and after transition from a pharmacist-managed anticoagulation clinic with physician-managed primary care.¹⁹ In pharmacist-managed care, before transition, 76% of patient INRs were within the target range, compared with 48% after transition to primary care (P < 0.0001). Similarly, the number of INRs within the target range for each patient was lower after transition to primary care (75% versus 36.5%, P < 0.0001). Before transition from the anticoagulation clinic, two emergency department visits for symptoms related to bleeding were reported. After transition to primary care, 13 cases of additional medical care were reported, 12 bleeding related and one thrombosis related. Six resulted in emergency room visits. This was a statistically significant increase in the number of cases requiring medical care after transition from the pharmacist-managed clinic (two versus 13, P = 0.0412). The severity of these events was not reported. The perceived quality of care based on a patient satisfaction survey was higher for pharmacist-managed care.

No systematic reviews were identified comparing different models of specialized clinic care. One RCT²⁰ and two non-randomized studies^18,21 compared different specialized services. The results of these studies are summarized in Table 3 and Appendix 4.

Table 3

Summary of Results for Comparison of Specialized Care Models.

In a 2006 RCT,²⁰ patients already on warfarin were randomized to either continue “traditional” hospital-based clinic care or to receive nurse-led primary care using POC testing and a computer decision support system. Patients assigned to nurse-led primary practice care showed a statistically significant improvement in TTR over the study period (initial: 57% [95% CI 50% to 63%], final: 69% [95% CI 66% to 73%], P < 0.01). Improvements were also shown in the control population, but statistical analysis was not provided. At the end of the study period, patients receiving nurse-led primary care had a significantly higher TTR (69%, 95% CI 66% to 73%) compared with those receiving hospital-based care (57%, 95% CI 50% to 63%, P < 0.01). No significant difference was reported in overall death rate or serious adverse events, including transient ischemic attack, stroke, or epistaxis. In the total study population, there were 39.8 minor, 0.4 major, and no fatal hemorrhagic events per 100 patient-years. For thromboembolic events, there were 3.9 serious and 0.79 fatal events per 100 patient-years.

One retrospective chart review¹⁸ compared UC by the patient’s primary care provider with either pharmacist- or nurse-managed anticoagulation services. In this comparison, TTR was significantly higher for pharmacist-managed care (83.6% versus 71.8%, P < 0.05). Hospitalization rate was higher for nurse-managed care compared with pharmacist-managed care (12.3 versus 5.4 per 100 patient-years, RR 2.29, 95% CI 1.23 to 4.25). Similarly, the rate of emergency department visits (expressed as number per 100 patient-years) was higher for nurse-managed care compared with pharmacist-managed care (5.6 versus 1.2, RR 4.45, 95% CI 1.42 to 13.98).

A comparison between a secondary care-based anticoagulation clinic and primary care-based practice using POC monitoring and computer-based decision support showed no statistically significant difference in TTR.²¹ During 12 months of secondary care management, patients had an average TTR of 76.4%. In 12 months of primary care management, the mean TTR was 72.1%. This reduction of 5.6% from secondary care (a difference of 4.3) was not statistically significant (95% CI –2.7% to +13.9%).

Patient Self-testing and Patient Self-management

Six HTAs, systematic reviews, or meta-analyses were identified that compared PST or PSM with other care.^{33,35,38–41} Results are summarized in Table 4 and Appendix 3.

Table 4

Summary of Results for PST/PSM.

In 2011, the US Department of Veterans Affairs published a systematic review comparing PST, alone or in combination with PSM, with care delivered in specialized or non-specialized clinics.³³ The results of this review were also reported elsewhere.⁴² The review identified 27 articles describing 22 distinct RCTs including a total of 8,413 participants.

There was a lower rate of overall mortality (OR 0.74, 95% CI 0.63 to 0.87) and thromboembolic events (OR 0.58, 95% CI 0.45 to 0.75) in patients randomized to PST/PSM compared with other care. Patients assigned to PST/PSM also had a lower rate of major bleeding events (OR 0.89, 95% CI 0.75 to 1.05), but this result was not statistically significant. Mean TTR for patients randomized to PST/PSM was 66.1% (range of means 56% to 76.5%) compared with 61.9% (range 32% to 77%) for patients randomized to other care groups. This difference was not statistically significant. Eleven included studies reported patient satisfaction and quality of life. Measurement and definition varied across the studies but, in general, patients in the PST/PSM group expressed greater treatment satisfaction or quality of life. Three studies reported significantly higher self-efficacy and less distress, fewer daily hassles, and reduced strain on social networks with PST/PSM. One reported improved emotional health and vitality. Four additional studies showed a significant difference in treatment satisfaction in PSM/PST patients. Three included studies reported no significant difference in patient satisfaction or quality of life.

A 2010 systematic review by Garcia-Alamino et al.³⁹ included 26 papers reporting on 18 RCTs (4,723 participants).

Meta-analysis indicated that patients who self-managed or self-tested were at decreased risk of thromboembolism (RR 0.50, 95% CI 0.36 to 0.69), overall mortality (RR 0.64, 95% CI 0.46 to 0.89), and minor hemorrhage (RR 0.64, 95% CI 0.54 to 0.77). When PST was considered by itself, no significant difference in mortality (RR 0.84, 95% CI 0.50 to 1.41) or thromboembolism (RR 0.57, 95% CI 0.32 to 1.00) was observed compared with other care. Rates of major hemorrhage were not different between PST/PSM patients and other care (RR 0.87, 95% CI 0.66 to 1.16); however, there was a statistically significant reduction in patients self-testing only (RR 0.56, 95% CI 0.35 to 0.91). Results were also reported based on clinical condition. However, only two included studies examined atrial fibrillation exclusively and event rates were low; therefore, no statistically significant differences in adverse events were reported in this group.

Thirteen included trials reported percentage of INR measurements within the target range. All but one reported improvements in PSM and PST groups, with six of these reporting statistically significant differences. Eleven trials reported TTR. Three of these (n = 554 patients) observed a statistically significant improvement in TTR in the PST and PSM groups, while eight (n = 2,059 patients) showed no significant difference between PST/PSM and other care. Results for these outcomes were not pooled. Eight included studies evaluated quality of life outcomes using various measures and definitions. Five showed a statistically significant improvement in quality of life or treatment satisfaction in PST or PST/PSM patients. The remaining three studies showed no significant difference between the study groups.

In a 2009 systematic review and meta-analysis, Cios et al.³⁵ evaluated the impact of study setting on INR control in US studies. The analysis included 24 studies (43 study groups) performed in an anticoagulation clinic (the study was performed in a clinic, or the stated role of clinicians in patient care was limited to anticoagulation management) or community practice (the study could not be classified as an anticoagulation clinic or RCT). Subgroup analysis showed PSM is associated with a TTR of 58% (95% CI 47% to 51%), while TTR in the other groups was 57% (95% CI 55% to 59%). After meta-regression using a mixed-method model controlling for study setting, year, design, and other study-level factors, the adjusted difference (−8.9, 95% CI −25.7 to −7.8) was not statistically significant. In a post-hoc analysis, Canadian warfarin studies were included, with similar results. With Canadian studies included, TTR was 65% (95% CI 55% to 76%) with PSM and 59% (95% CI 56% to 61%) without PSM, a non-statistically significant difference (−2.0, 95% CI −15.3 to 11.2).

A 2007 meta-analysis on the safety and effectiveness of POC monitoring devices in anticoagulation therapy included a subgroup analysis of PST/PSM.⁴⁰ Patients using a POC device for self-testing and self-management had significantly lower rates of both major thromboembolism (OR 0.48, 95% CI 0.30 to 0.79) and overall thromboembolic events (OR 0.45, 95% CI 0.24 to 0.84) and death (OR 0.48, 95% CI 0.24 to 0.94) compared with patients receiving care from an anticoagulation clinic or individual practitioner without use of a POC device. No significant difference was observed for major hemorrhagic events (OR 0.75, 95% CI 0.47 to 1.20). TTR was higher for PST/PSM patients compared with other care (71% versus 63%, no statistical analysis provided). Analysis separately comparing either clinic or practitioner care with PST/PSM was not performed.

A 2007 HTA⁴¹ included a systematic review of the clinical effectiveness, comparing PST/PSM with other anticoagulation management strategies. The review identified 16 RCTs and eight non-RCTs.

Meta-analysis of RCTs and non-randomized studies was used to calculate risk difference (RD) for major complications and death. PST/PSM was associated with reduced risk of thromboembolic events (RD −0.02, 95% CI −0.03 to −0.01) and death (RD −0.017, 95% CI −0.029 to −0.005), but not hemorrhagic events (RD −0.004, 95% CI −0.015 to 0.007). An odds ratio method was also used for RCTs only, but results did not differ.

Among 12 RCTs that reported TTR, the pooled estimate was 67.4% for PST/PSM and 63.4% for UC. When separated according to type of care used as a control, PST/PSM resulted in a similar TTR to specialized clinics (67.1% versus 66.3%) but a higher TTR compared with primary care by family doctors (74.8% versus 59.8%). Two non-randomized studies reported TTR, finding significantly better time in range in the PSM group compared with UC. These results were not pooled. Non-RCTs reporting the number of INR measurements within the therapeutic range were pooled and showed better INR control with PSM, compared with UC (82.9% versus 69.5%). Six included studies reported on quality of life, according to different metrics. Three indicated improved quality of life and patient satisfaction with PST/PSM, while three reported no significant difference between PST/PSM and other care.

A 2006 systematic review by van Walraven et al.³⁸ examined the effect of study group characteristics on anticoagulation control. A total of 67 studies incorporating 123 study groups were included. Of these, seven trial groups involved PSM and 116 had no self-management aspect. Patients who self-managed had a mean TTR of 71.5% (95% CI 65.2% to 77.7%), and those using usual clinic or community practice care without self-management had a mean TTR of 63.1% (95% CI 61.0% to 65.2%). The adjusted effect of 7.0% increase in TTR (95% CI 0.7% to 13.3%) was statistically significant (P = 0.03).

Seven additional studies were identified comparing PST/PSM with other models of anticoagulant care. Five of these compared PST or PSM with other specialized anticoagulation services^22–26 and two compared with UC.^27,28 Results are summarized in Table 4 and Appendix 4.

A 2011 RCT²² compared patient self-testing using a telemedicine system with treatment in a hospital-based clinic. Patients who self-tested measured INR once or twice a week using a POC device, reporting values to the anticoagulation clinic via an online system. Dose adjustments were made by the clinic and reported using the same system. Patients randomized to traditional clinic care made clinic visits at minimum every four weeks for INR measurement and dose adjustment, but at shorter intervals depending on warfarin dose changes.

TTR was reported for each group. Compared with patients receiving conventional clinic care (72.7%, 95% CI 71.9% to 73.4%), patients had a significantly higher TTR when self-testing either once (79.7%, 95% CI 79.0% to 80.3%) or twice (80.2%, 95% CI 79.4% to 80.9%) per week. The difference in TTR between patients testing once or twice was not significant (P = 0.2516). No patients died during the trial. One adverse event (hospitalization) was reported, but the care group for this patient was not described.

Results of a survey published in 2011²³ examined quality of life changes in patients randomized to receive routine care, either attending a hospital or practice-based anticoagulation clinic, or self-managing with INR testing every two weeks. Questionnaires were sent to participants at the baseline and after 12 months of receiving assigned treatment. Questionnaires used two instruments: one measured anxiety; the other reported on treatment-related quality of life. Overall, a greater improvement in self-efficacy was reported in the PSM group compared with clinic care (1.67 versus 0.43, P = 0.01). This association remained statistically significant after adjusting for age (P = 0.03). No statistically significant differences between PSM and clinic care were observed for changes in daily hassle, psychological distress, treatment satisfaction, or anxiety over the study period.

In 2009, Gardiner et al.²⁴ examined whether PST is a viable alternative to hospital anticoagulation clinic attendance for anticoagulation management. Patients who self-tested used a POC device to measure INR every two weeks. Results were reported to the anticoagulation clinic where dose adjustment was carried out, using computer dosing software. Patients who did not want to self-monitor received routine care in the anticoagulation clinic. Details of this care were not described. The median TTR was higher in the PST group (71%, 95% CI 64.1% to 75.3%) compared with those receiving routine care (60%, 95% CI 55.0% to 63.2%, P = 0.003). Among patients who were self-testing, the incidence of major bleeds was 1.7 per 100 patient-years, incidence of minor bleeds was 8.4 per 100 patient-years, and incidence of thrombosis was 3.4 per 100 patient-years. In the routine care group, the incidence of major bleeds, minor bleeds, and thrombosis was 5.4, 16.2, and 1.4 per 100 patient-years, respectively. No statistical analysis was done on adverse event rates.

A 2008 before-after study²⁵ compared PSM with management provided by an anticoagulation clinic. The PSM group monitored INR every one or two weeks (after an initial three-week training period) and reported measurements using an Internet-based system. A dosing algorithm provided dosing recommendations directly to the patient, or in more extreme INR deviations, to the physician for approval. The mean time in therapeutic range increased from 63.0% during the control period (before introduction of the PSM system) to 74.4% after PSM was introduced, for a mean difference of 11.4% (95% CI, 5.5% to 17.3%, P < 0.004). No hemorrhagic or thromboembolic complications were reported during either study period.

A 2007 retrospective study²⁶ examined the clinical effectiveness of PSM outside of trial conditions. Patients were selected from a previous RCT comparing PSM with routine care. PSM patients self-managed their warfarin based on INR testing every two weeks. Control patients had their warfarin managed in hospital or practice-based anticoagulation clinics and continued to do so post-trial. In PSM patients, there was no statistically significant difference in TTR between trial and post-trial periods (75% versus 70%, P = 0.12). Similarly, no significant difference was observed in the control arm outside of trial conditions (64% versus 57%, P = 0.09). No significant differences were found between the change in mean TTR in PSM during and post-trial compared with the control arm (P = 0.54).

In a 2011 before-after study,²⁷ anticoagulation control in patients receiving laboratory INR testing followed by dose adjustment by the lab or general practitioner was compared with the same group of patients after the introduction of a PSM program. There was no significant difference in the overall TTR between the two groups (PSM 81.3% versus UC 72.4%, P = 0.16). In patients with poor control (TTR < 60%) prior to self-management, switching to PSM resulted in a statistically significant improvement in TTR (UC 38.8% versus PSM 71.1%, P = 0.01). There was no significant difference in patients who had good INR control (TTR > 60%) after switching to PSM (UC 83.0% versus PSM 82.5%).

A 2008 study²⁸ compared PST followed by dose adjustments by a general practitioner using a decision support tool with anticoagulation therapy monitored and controlled by the patient’s general practitioner (UC). Mean individual TTR was not significantly different between groups (PST 65.7% versus UC 66.4%, P = 0.85). No statistically significant differences between PST and UC for adverse events, including death (5.5% versus 5.5%, P = 1.0), major hemorrhagic complications (0% versus 1.8%, P = 1.0), minor hemorrhagic complications (7.4% versus 3.7%, P = 0.67), and thromboembolism (1.8% versus 3.7%, P = 1.0), were observed. Compared with results from pre-study questionnaires, PST was associated with greater decreases in dissatisfaction (−0.8 versus 0.2, P = 0.001) and stress (–0.3 versus 0.005, P = 0.003), fewer limitations to daily activities (−0.2 versus 0.3, P = 0.005), fewer social problems (–0.1 versus 0.3, P = 0.03), and decreased anxiety (−2.5 versus 2.3, P = 0.04) over the study period compared with UC.

Other

Four identified studies^29–32 compared computer-assisted with manual anticoagulant dosing by experienced staff. All four studies reported increases in TTR with computerized dosing algorithms, though one³² did not report the statistical significance of the result. This study examined TTR by indication and found an increase in TTR in AF patients from 46% in 1992 using cardiologist-based manual dosing to 81% in 2006 using computer-assisted dosing in the same practice. Three studies^29–31 reported adverse events and found no significant difference in bleeding events, hemorrhagic events, or deaths between the two groups.

One systematic review³³ identified two studies comparing PSM with PST including clinic care and found no statistically significant difference in TTR between the two groups. One of these studies reported quality of life outcomes and reported greater treatment satisfaction in the PST group compared with PSM.

One meta-analysis⁴⁰ compared the use of POC INR testing devices in any setting with “usual care,” defined as laboratory INR testing with clinic or primary care management. Seventeen relevant articles reporting on 16 individual trials found no significant difference in major hemorrhage rate with POC testing compared with UC (OR 0.75, 95% CI 0.51 to 1.10). Use of POC devices was associated with a reduction in thromboembolism (OR 0.45, 95% CI 0.29 to 0.70) and mortality (OR 0.54, 95% CI 0.35 to 0.83). TTR was higher with POC device use (69% versus 61%), but no statistical analysis was reported.