Quels facteurs associés à la survenue d’un événement iatrogène hémorragique chez les patients sous antivitamines K ?

Evaluation of anticoagulant therapy management in a teaching hospital in Tunisia: information and education for vitamin k antagonist newly treated patients need to be improved

OBJECTIVE

The objective of this study was to assess the level of Vitamin K antagonist (VKA) therapy knowledge among VKA newly treated patients.

METHODS

Questionnaire-based interviews were administered in a university hospital to VKA newly treated patients covering both cognitive (i.e. indication, route of administration, treatment monitoring and side effects) and know-how (i.e. safety precautions, what affects anticoagulant therapy and the management of overdose signs) aspects of therapy knowledge.

KEY FINDINGS

A total of 55 patients were included. The mean overall score of patients' knowledge was 5.78 (SD = 3.425) out of 20. The mean scores of cognitive and practical knowledge were 3.8 (2.26) and 1.98 (1.78) out of 10, respectively. Factors associated with an insufficient level of VKA therapy knowledge included low level of education, lack of access to therapy information and continuous access to this information.

CONCLUSIONS

Knowledge about VKA therapy among newly treated patients is insufficient. Patient's medication knowledge should be improved to ensure better adherence.

Relationship between the nutritional status and safety and efficacy outcomes in atrial fibrillation patients aged 80 years and over receiving oral anticoagulants

BACKGROUND

Malnutrition has been reported to be associated with worse clinical outcomes in various cardiovascular diseases. We aimed to investigate the clinical significance of the nutritional status in atrial fibrillation (AF) patients aged 80 years and over receiving oral anticoagulants (OACs), focusing on the difference between direct OACs (DOACs) and warfarin treatment.

METHODS

This was a retrospective and observational study. We enrolled 332 consecutive AF patients aged 80 years and over who were treated with OACs: DOACs (n = 256) and warfarin (n = 76). A controlling nutritional status (CONUT) score was used to evaluate the nutritional status. The enrolled patients were divided into two groups based on the CONUT score: CONUT score <5 (n = 239) and CONUT score ≥5 (n = 93) groups. We investigated the relationship between the nutritional status and clinical outcomes.

RESULTS

The CONUT score ≥5 group had significantly higher incidence of major bleeding (MB) compared to the CONUT score <5 group (4.6/100 person-years vs. 0.7/100 person-years, p < 0.01). On Cox hazard analysis, CONUT score ≥5 group was significantly associated with increased MB compared with the CONUT score <5 group (hazard ratio: 5.80, 95% confidence interval: 1.44-23.33, p = 0.013). In the DOAC group, the incidence of MB did not differ between the CONUT score ≥5 and CONUT score <5 groups (p = 0.54). In the warfarin group, MB occurred more frequently in the CONUT score ≥5 group than CONUT score <5 group (p < 0.01). There was no significant difference in the incidence of thromboembolic events between the CONUT score ≥5 and CONUT score <5 groups in both the DOAC and warfarin groups.

CONCLUSIONS

The prognostic values of the nutritional status based on the CONUT score for MB differed between AF patients aged 80 years and over receiving DOACs and those receiving warfarin. It may be favorable to use DOACs to avoid bleeding events in those with malnutrition.

Evaluation of oral anticoagulants in atrial fibrillation patients over 80 years of age with nonsevere frailty

BACKGROUND

The safety and efficacy of an oral anticoagulant (OAC) treatment and the difference between direct OACs (DOACs) and warfarin in nonsevere frail elderly patients with AF are unclear.

METHODS

This was a retrospective and observational study of 354 patients over 80 years of age with nonsevere frailty who were diagnosed with AF and treated with OACs. Nonsevere frailty was defined as a clinical frailty scale score of <7. Bleeding and thromboembolic events during the OAC treatment were followed up.

RESULTS

Of 354 patients enrolled, 273 (77.1%) received DOACs and 81 (22.9%) received warfarin. Of 273 patients receiving DOACs, there were 210 (76.9%) prescribed with appropriate doses of DOACs. Of 81 warfarin-treated patients, 53 (65.4%) were prescribed an appropriate dose of warfarin. During a follow-up of 33.1 (14.0-51.0) months, 15 patients (1.5/100 person-years) had bleeding events and 10 (1.0/100 person-years) had thromboembolic events while on an OAC treatment. The incidence ratio of bleeding events in patients receiving DOACs was lower than that in those receiving warfarin (1.0/100 person-years vs 2.9/100 person-years, hazard ratio [HR]: 0.26, 95% confidence interval [CI]: 0.07-0.91, P = .036). There was no significant difference in the incidence of thromboembolic events between the DOAC and warfarin treatment groups (0.88/100 person-years vs 1.4/100 person-years, HR: 0.63, 95% CI: 0.16-2.57, P = .52).

CONCLUSIONS

OACs are substantially safe and effective for preventing thromboembolic events in nonsevere frail patients over 80 years of age. Particularly, DOACs can be used more safely than warfarin.

Bleeding and asymptomatic overdose in patients under Vitamin K antagonist therapy: Frequency and risk factors

Background

Vitamin K antagonists are widely used in the treatment and prevention of thromboembolic disease. However, these drugs can cause serious side effects, especially bleeding. This study aims to evaluate frequency and risk factors of both bleeding and asymptomatic overdose in North African patients undergoing Vitamin K antagonist therapy.

Methods

We performed a cross-sectional study in patients undergoing Vitamin K antagonist therapy. A statistical analysis has been conducted to identify overdose and bleeding risk factors by using chi-square test (p < .05).

Results

One hundred and eleven patients were included. We recorded 14 cases of bleeding and 26 cases of asymptomatic overdose. Advanced age, poor adherence, concomitant use of paracetamol and history of previous bleeding are significant risk factors of over-anticoagulation. An INR value over 6 at admission, a high therapeutic target range for INR, concomitant use of acetylsalicylic acid, lack of information on overdose signs and measures to be taken in case of bleeding were identified as risk factors for bleeding.

Conclusion

Most of the risk factors identified in our study seem to be related to patients lack of information and education. These results highlight the importance of creating a therapeutic patient education program.

[Overdose in Vitamin K antagonists administration in Dakar: epidemiological, clinical and evolutionary aspects]

Vitamin K antagonists (VKA) are widely used for the prevention and curative treatment of thromboembolic events. This study aims to describe the epidemiological, clinical and evolutionary aspects of overdose in Vitamin K antagonists administration and determine its hemorrhagic factors. We conducted a monocentric cross-sectional descriptive study at the Principal Hospital in Dakar. All patients with an INR greater than 5 were included. We studied patients' gender and age, VKA used, drug use period, indications, INR value, associated drugs, presence of hemorrhage, immediate management and evolution. We enrolled 154 patients. Acenocoumarol was the most prescribed VKA. Sex ratio favoured women. The average age was 63 years. Overdose was asymptomatic in 43% of patients. Hemorrhagic symptoms were mainly represented by gingival bleeding, epistaxis. Major bleeding episodes were found in 8.6% of patients and they were represented by melena in 6 patients (3.9%), deep muscle hematoma in 2 patients (1.3%) and intracerebral parenchymal hematoma in 2 patients. Two patients had cardiovascular collapse associated with deglobulisation. Nonsteroidal anti-inflammatory drugs (NSAIDs) assumption was noted in 21% of patients. VKA assumption was suspended transiently in all patients. Mortality was 2%, due to intracranial hemorrhage. The reduction in VKA overdose requires caregivers to manage overdose factors and provide proper patient education.

Risk factors associated with a thrombotic or bleeding event in patients treated with vitamin K antagonists

AIM

To identify, in a case-control study, the risk factors associated with a thrombotic or bleeding event in patients treated with vitamin K antagonists.

MATERIALS AND METHODS

We performed a single-centre observational study during a three-month period where we consecutively included patients admitted to the emergency department of a secondary-level hospital and treated with vitamin K antagonists, regardless the reason for admission. Patients admitted for a thrombotic or bleeding event were included as cases and the other patients served as controls. Main thrombotic or bleeding risk factors during vitamin K antagonist therapy were a priori identified in literature and tested in conditional logistic regression.

RESULTS

Two hundred and forty subjects were identified, 40 of which (17%) were admitted for a bleeding event, 19 (8%) for a thrombotic event and 181 (75%) for another reason. Over 85% of patients were treated with fluindione. No risk factor was significantly associated with bleeding or thrombotic event in patients treated with vitamin K antagonist. Patients presenting a thrombotic event were however more likely to have a chronic respiratory disease.

CONCLUSIONS

In this study, no risk factor significantly associated with a bleeding or thrombotic event in patients treated with vitamin K antagonist were identified. The occurrence of these events supposes other risk factors, including potential genetic polymorphisms that should be considered in future studies.

[Risk factors of serious bleeding among ambulatory patients taking antivitamin K aged 75 and over]

The benefits of anti-vitamin K (AVK) drugs have been acknowledged in several indications. Such indications increasing with increasing age, AVK prescriptions also increases with age. At the same time, conditions involving significant bleeding are common in this elderly population. It is thus essential to recognize the determining factors. This study included all patients taking AVK drugs aged 75 years and older who sought emergency care at the Cochin Hospital from January to December 2011 for significant bleeding. These patients were compared with a cohort of patients aged 75 years or older who were taking AVK drugs and who were admitted to the same unit during the same time period for other reasons. The case-control comparison included demographic data, comorbidity factors, multiple medications, emergency measured INR, and CHA2DS2VASC level. The hemorrhagic risk was evaluated by HEMORR2HAGES and HAS-BLED. A total of 34 patients were studied and compared with 70 case-controls. The Charlson comorbidity index was higher in patients than case-controls (P<0.05), with a much higher hemorrhagic risk for scores ≥ 9 (OR=2.5; P<0.05). Multiple medication was also more predominant in patients (P<0.05). The risk of serious hemorrhage was also higher when the hemorrhagic scores were high, especially for HEMORR2HAGES (P<0.0001) and HAS-BLED (P<0.001). The risk of serious hemorrhage in elderly outpatients taking AVK drugs is related to their higher comorbidity and hemorrhagic levels which need to be evaluated before starting or stopping AVK treatment.

Adverse drug events associated with vitamin K antagonists: factors of therapeutic imbalance

Background

Adverse drug events (ADE) occur frequently during treatment with vitamin K antagonists (AVK) and contribute to increase hemorrhagic risks.

Methods

A retrospective study was conducted over a period of 2 years. Patients treated with AVK and admitted to the emergency room of a tertiary care hospital in Beirut were included. The aim of the study was to identify ADE characterized by a high international normalized ratio (INR) and to determine the predictive factors responsible for these events. Statistical analysis was performed with the SPSS statistical package.

Results

We included 148 patients. Sixty-seven patients (47.3%) with an INR above the therapeutic range were identified as cases. The control group consisted of 81 patients (54.7%) with an INR within the therapeutic range. Hemorrhagic complications were observed in 53.7% of cases versus 6.2% of controls (P < 0.0001). No significant difference was noticed between cases and controls regarding the indication and the dose of AVK. Patients aged over 75 years were more likely to present an INR above the therapeutic range (58.2%, P = 0.049). Recent infection was present in 40.3% of cases versus 6.2% of controls (P < 0.0001) and hypoalbuminemia in 37.3% of cases versus 6.1% of controls (P < 0.0001). Treatment with antibiotics, amiodarone, and anti-inflammatory drugs were also factors of imbalance (P < 0.0001).

Conclusion

Many factors may be associated with ADE related to AVK. Monitoring of INR and its stabilization in the therapeutic range are important for preventing these events.