RESUMEN
PURPOSE: To analyze the impact of a 12-week extended International Normalized Ratio (INR) follow-up interval on healthcare use. METHODS: A prospective cohort study of the use of an extended INR follow-up interval of up to 12 weeks was conducted over 2 years in a pharmacist-managed anticoagulation clinic. A detailed protocol was used to extend the INR follow-up interval to 5-6 weeks and then 7-8 weeks and 11-12 weeks. The number of planned and unplanned anticoagulation encounters, procedures requiring warfarin interruption, telephone triage phone calls, emergency department visits, and hospitalizations were collected. A post hoc subanalysis was also completed on participants who were scheduled for 4 consecutive 12-week intervals. RESULTS: Compared to baseline, at 12 months there was a mean decrease in planned anticoagulation encounters of 2.24 visits (p < 0.001) among 44 participants. From 12 to 24 months compared to baseline, there was a mean decrease in planned anticoagulation encounters of 3.13 visits (p < 0.001) and an increase of 0.54 unplanned anticoagulation encounters (p = 0.04) among 39 participants. The remainder of healthcare use variables were not statistically significantly different from baseline at any time point. Of the 15 participants scheduled for 4 consecutive 12-week intervals, there was a decrease from baseline of approximately 5 visits over the course of a year (p < 0.001). CONCLUSION: An extended INR follow-up interval appears to decrease anticoagulation healthcare use without an increase in acute healthcare use. While this intervention could be cost-effective, institutions need to consider safety, efficacy, and feasibility prior to implementation.
Asunto(s)
Anticoagulantes/administración & dosificación , Anticoagulantes/uso terapéutico , Relación Normalizada Internacional , Aceptación de la Atención de Salud , Warfarina/administración & dosificación , Warfarina/uso terapéutico , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Monitoreo de Drogas , Servicios Médicos de Urgencia/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Servicio de Farmacia en Hospital , Estudios Prospectivos , TriajeRESUMEN
The 2012 American College of Chest Physicians' guidelines recommended a 12-week INR follow-up interval may be appropriate for patients on stable warfarin doses. Limited evidence supports this recommendation. A single-arm, prospective cohort study over 24 months was completed in a Veterans Affairs anticoagulation clinic to determine the long-term feasibility and safety of implementing an extended INR follow-up interval in Veterans on stable doses of warfarin. Participants were required to have a stable warfarin dose for 6 months prior to enrollment. A prespecified protocol was used to titrate, extend, and manage the INR interval up to 12 weeks. Scheduling of extended INR intervals was a primary outcome. Safety outcomes included major and serious bleeding and thromboembolic events. A post-hoc comparison of baseline characteristics between individuals who were scheduled for at least 4 consecutive 12-week INR follow-up intervals and those who were not was completed. Of the 50 participants, 36 (72%) were scheduled for at least one 12-week interval and 15 (30%) were scheduled for 4 consecutive intervals. There were 2 thromboembolic events that occurred in 1 participant. There were 28 major and serious bleeding events in 19 participants; 8 occurred while on the extended INR interval. In the post-hoc analysis, no participants scheduled for 4 consecutive 12-week intervals had heart failure. Based on 2 years of monitoring, a 12-week INR follow-up interval using a detailed protocol with titration of INR interval extension appears feasible for a subset of patients. Patients with heart failure may not be suitable for this intervention.
Asunto(s)
Instituciones de Atención Ambulatoria , Anticoagulantes/administración & dosificación , Coagulación Sanguínea/efectos de los fármacos , Monitoreo de Drogas/métodos , Relación Normalizada Internacional , Anciano , Anticoagulantes/efectos adversos , Estudios de Factibilidad , Hemorragia/inducido químicamente , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , United States Department of Veterans AffairsRESUMEN
A prospective, single-arm study of 50 participants evaluated an extended INR follow-up interval to determine the implementation feasibility and safety of an extended interval in Veterans on a stable dose of warfarin. A protocol was designed to allow for a rigorous, yet pragmatic evaluation of a 12-week INR follow-up interval. Feasibility was determined by study enrollment, retention, and participant achievement rates for the extended INR interval. Safety was determined by bleeding and thromboembolism rates. Participants were monitored for 6 months. Despite the long-term stability of participants prior to enrollment, only 56% achieved a 12-week follow-up interval and only 34% of enrolled participants maintained a 12-week interval. Sixteen percent of participants were never eligible for an extension of their INR follow-up interval despite meeting initial enrollment criteria. There were two major bleeding events and one participant who experienced a thromboembolic event. Implementation of an extended interval of INR follow-up appears feasible as participant enrollment goals were met and pharmacists were able to follow the study protocol. However, a lower than expected proportion of participants were able to achieve and maintain an extended INR follow-up interval. Future evaluations are needed to confirm the safety of an extended INR interval.