Warfarin therapy in older adults: managing treatment in the primary care setting

Standardized warfarin monitoring decreases adverse drug reactions

Background

While warfarin is the most commonly prescribed medication to prevent thromboembolic disorders, the risk of adverse drug reactions (ADR) poses a serious concern. This prospective study evaluated how primary care providers (PCP) and cardiologists at our Institution managed patients treated with warfarin with the goal of decreasing the number of warfarin ADRs.

Methods

A multidisciplinary anticoagulation task force was established at our Institution in 2014 to standardize warfarin monitoring and management. Between 2013 and 2017, we analyzed patients who were prescribed warfarin by their PCP or cardiologist upon hospital discharge and in the ambulatory setting to determine the international normalized ratio (INR) within 5, 10, and 30 days after discharge, time in therapeutic range (TTR), number of severe warfarin ADRs, and total and average cost reduction of all severe warfarin ADRs to determine whether there was an organizational cost savings following the implementation of standardized warfarin care.

Results

The warfarin ADR rate significantly decreased over the 5-year period, from 3.8 to 0.98% (p < 0.0001). The proportion of warfarin prescriptions out of all anticoagulants significantly decreased, from 72.2 to 42.1% (p < 0.001). The proportion of individuals who received an INR at 5, 10, and 30 days after hospital discharge compared to the total number of patients prescribed warfarin significantly increased (p < 0.001). The total cost of severe warfarin ADRs decreased by 57.6% between 2013 and 2017.

Conclusions

This study serves as a model to reduce the number of severe warfarin ADRs by the following tactics: (1) educating PCPs and cardiologists about evidence-based guidelines for warfarin management, (2) increasing the use of our Institution’s electronic warfarin module, and (3) enhancing patient compliance with obtaining INR.

Bleeding complications during warfarin treatment in primary healthcare centres compared with anticoagulation clinics

OBJECTIVES

To examine determinants of bleeding complications during warfarin treatment in an unselected patient population and evaluate possible differences in safety between specialized anticoagulation clinics and primary healthcare centres.

DESIGN

Prospective cohort study. Data were collected with an admission form and medical records were scrutinized in order to pursue all adverse events. Differences between groups were estimated with a t-test and chi-squared test, and univariate and multivariate Cox regression analysis.

SETTING

All patients treated and monitored with oral anticoagulation in primary healthcare centres and specialized anticoagulation clinics in the Sundsvall and Skellefteå region (northern Sweden) during a five-year period.

SUBJECTS

A total of 2731 patients corresponding to 5044 treatment years.

MAIN OUTCOME MEASURES

Bleedings were classified as fatal or major. Major bleedings were defined as an event causing admission, prolonged in-hospital care or death.

RESULTS

In total 195 major bleedings occurred corresponding to 3.9% per treatment year, including 34 fatal events (0.67% per treatment year). Patients monitored at the two specialized anticoagulation clinics combined had a major bleeding frequency of 4.1% as compared with 3.9% at primary healthcare units. The frequency of fatal haemorrhage was 0.57% and 0.76%, respectively. The rate of major and fatal bleeding was age related with an increase of 4% and 5%, respectively, per year.

CONCLUSIONS

There was no difference in bleeding complications between patients monitored at primary healthcare centres and specialized anticoagulation clinics. Age was continuously and independently associated with bleeding risk. These study data indicate the need to exercise caution in treatment of the elderly.

Anticoagulation in Ambulatory Care

PURPOSE OF THE MANUSCRIPT: Anticoagulation is warranted for the treatment of various disorders including cardiac, vascular, and postsurgical causes. Many centers have nurse case managers to coordinate care for patients on anticoagulation. This increases the demand for specific guidelines to assist nurse case managers to ensure quality of care. This review will address guidelines for nurse case managers and providers regarding initiating anticoagulation treatment and monitoring prothrombin time and international normalized ratio. Information will also be provided regarding when the nurse case manager should notify the providers to establish target international normalized ratio. This review will also provide educational tools to serve as standards for patient teaching, including drug and food interactions.

PRIMARY PRACTICE SETTING(S)

This article applies to adult ambulatory practice that includes primary care, cardiology, and vascular and surgical settings.

IMPLICATIONS FOR CASE MANAGEMENT PRACTICE

The complexity of managing anticoagulation in ambulatory practice warrants case management. The nurse case manager will establish a rapport with patients to improve compliance, providing patient education about diet, dosages, and drug interactions to reduce medication errors and bleeding complications. This review on anticoagulation management will assist nurse case managers and providers to provide better quality of care.