|Year : 2017 | Volume
| Issue : 3 | Page : 166-172
Knowledge base and practice among clinicians regarding oral anticoagulant therapy: A questionnaire survey
JD David Livingston1, M Joseph John2
1 Department of Medicine, Ruby Nelson Memorial Hospital, Jalandhar, Punjab, India
2 Department of Clinical Haematology, Haemato-Oncology, and Bone Marrow (Stem Cell) Transplant, Christian Medical College and Hospital, Ludhiana, Punjab, India
|Date of Web Publication||13-Jul-2017|
J D David Livingston
Ruby Nelson Memorial Hospital, C1, Cantonment Road, Jalandhar - 144 005, Punjab
Source of Support: None, Conflict of Interest: None
Purpose: To assess the knowledge of clinicians regarding various aspects of anticoagulant therapy. Materials and Methods: This cross-sectional study was done over 2 months among 55 clinicians at a tertiary hospital. A 30 point questionnaire based survey on various aspects of oral anticoagulant therapy was carried out. Clinician practices were also compared between physicians and surgeons. Results: Two thirds (67.3%) of the clinicians were not aware that different strengths of acitrom were not color coded. A majority (85.5%) verbally instructed their patients about the drug. Less than one fifths (18.2%) of the clinicians provided booklets and pamphlets for reference. Only 56.4% of clinicians were aware of the correct target range for INR to be achieved in patients. Dietary and drug history was not documented by 85.6% and 50.9% of clinicians respectively. Surgeons were more likely to give educational booklets to their patients, document a dietary history and instruct patients regarding concomitant alcohol use in comparison with physicians. Twenty (41.7%) clinicians reported that they encounter thrombosis as a complication in patients on OAT while 58.3% of the clinicians in the present study noted bleeding more often. Conclusion: There are significant lacunae in knowledge base among clinicians regarding oral anticoagulant therapy. More emphasis on physician education is needed for safe and optimal OAT in patients.
Keywords: Clinician, knowledge, oral anticoagulation therapy, practice, questionnaire
|How to cite this article:|
David Livingston J D, John M J. Knowledge base and practice among clinicians regarding oral anticoagulant therapy: A questionnaire survey. CHRISMED J Health Res 2017;4:166-72
|How to cite this URL:|
David Livingston J D, John M J. Knowledge base and practice among clinicians regarding oral anticoagulant therapy: A questionnaire survey. CHRISMED J Health Res [serial online] 2017 [cited 2018 Mar 24];4:166-72. Available from: http://www.cjhr.org/text.asp?2017/4/3/166/210482
| Introduction|| |
Oral anticoagulation therapy (OAT) use in clinical practice has been increasing steadily over the years for the prophylaxis and treatment of several thromboembolic conditions. OAT is associated with a narrow therapeutic index and optimal control is affected by many factors. These include inter- and intra-patient variability, dosage pattern, intensity of anticoagulation achieved, comorbid illnesses, concurrent drug therapy, dietary habits, physician's skill, and patient's compliance. Managing long-term oral anticoagulation therapy involves frequent laboratory testing, strict dosage regulation, recognition, and prompt treatment of thrombotic as well as hemorrhagic complications., Clinician knowledge and practices thus are key factors in OAT. There is enough evidence that inappropriate management rather than patient noncompliance or other aberrations are important factors in morbidity and mortality among patients on OAT.,
| Materials and Methods|| |
This cross-sectional study was done over a period of 2 months (August–September 2013) at a tertiary care 700 bed teaching hospital in North India. The aim was to assess the knowledge base of clinicians and practice regarding oral anticoagulant management in a tertiary care center. A questionnaire (Appendix 1 [Additional file 1]) with 30 questions regarding various aspects of management of patients on oral anticoagulant therapy (OAT) was used. The questionnaire was distributed among clinicians from cardiology, neurology, general medicine, cardiothoracic surgery, general surgery, neurosurgery, orthopedics and physical medicine, and rehabilitation services. The clinicians included senior consultants, junior consultants, and resident junior doctors who rotate in various units. Only clinicians with a minimum of 6 months of clinical experience were included. The questionnaires were personally handed over to the doctors in an envelope after verbal explanation regarding the study. Completed questionnaires were returned within a week to the office of the Department of Clinical Hematology and Oncology.
The questions pertained to (a) patient evaluation and education-the indications for starting OAT, drug used, their starting doses, the target international normalized ratio (INR) range defined, documentation of the dietary and drug history, baseline screens for coagulation, liver and renal functions, and whether information was given verbally or in print to patients regarding the risks of oral anticoagulants. (b) Management practices including the loading dose used by clinicians, their response to high INRs, intervals of INR testing after stoppage of the drug, the dose with which the drug is to be restarted, the knowledge of color of different strengths of the drug used, the clinicians' satisfaction with patient compliance and follow-up and the decisions made when encountered with different clinical scenarios.
Questions also related to practices followed while switching over from intravenous to oral anticoagulants and knowledge of the laboratory method being used to determine prothrombin time/INR.
Chi-square test was done to analyze the data. P < 0.05 was considered to be statistically significant.
This study was funded by the Department of Clinical Hematology, Hemato-Oncology and Bone Marrow (Stem Cell) Transplant Unit. Both authors have not received any grants and declared no conflict of interest with regard to this study. All procedures performed in this study were in accordance with the standards of the hospital ethics committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
| Results|| |
A total of 80 questionnaires were distributed, and 55 completed questionnaires were returned for a response rate of 65%.
Commonly used oral anticoagulant drug and initial dosage
Acitrom (Acenocoumarol) was the most frequently (78.9%) used oral anticoagulant agent. Warfarin and rivaroxaban were the other drugs used by 12.7% and 5.5% clinicians, respectively. Just over half (50.9%) of the clinicians stated the starting dose of acitrom to be 2 mg.
Indications for oral anticoagulation therapy
Deep vein thrombosis was the most common indication for OAT (89.1%) followed by atrial fibrillation (49.1%) [Table 1].
Knowledge of color of oral anticoagulant drug
Only 12 (21.8%) clinicians were aware that OAT drugs of different strengths were not color coded. One-fifth (20%) of the clinicians reported that the OAT drugs were color coded while 47.2% of the clinicians were unaware whether color coding was being followed for different strengths of the oral anticoagulant drugs.
Patient knowledge and compliance regarding oral anticoagulation therapy
Although 85.5% of clinicians gave verbal information to patients regarding OAT, booklets/pamphlets on OAT were provided by only 18.2% clinicians. Only 58.2% were sure of patient compliance most of the time. Just over two-third (69.1%) of the clinicians felt that their patients were aware of the effect of the drug on the body.
Less than one-fifths (14.6%) of clinicians felt that their patients kept their appointments regularly without fail while 72.73% clinicians opined that their patients missed an appointment occasionally and 3.6% frequently.
Approach to high international normalized ratio and time of testing
Various responses were obtained for questions pertaining to action taken by clinicians in response to high INRs seen in patients on OAT [Table 2].
|Table 2: The responses obtained with regard to high international normalized ratio and time of testing|
Click here to view
OAT was started on the same day of heparin treatment by 30.9% of the clinicians, 29.1% started OAT after 72 h, 25.5% after 48 h, and 9.1% clinicians after 24 h of heparin therapy.
Oral anticoagulation therapy in relation to diet, drug, alcohol, pregnancy, and other ailments
A detailed dietary history was not recorded in the case records of patients by 85.6% of clinicians before starting OAT. More than half (58.9%) of the clinicians instructed patients about drugs to be avoided while they were on OAT. However, the drug history was not documented by 50.9% clinicians in the patient's case records. Further, 56.4% did not instruct patients on precautions regarding concomitant alcohol consumption while on OAT.
Under two-thirds (61.8%) of the clinicians did not instruct the patients regarding medications to take if they had a headache, common cold, or any other ailment. More than half (65.5%) of the clinicians felt their female patients in the reproductive age group did not know what to do if they conceived while on OAT.
For patients to be started on OAT, a baseline coagulation screen, and a renal function test was done by 90.9% and 83.6% of clinicians, respectively.
More than four-fifths (83.6%) of the clinicians agreed that anticoagulant treatment policy aimed at achieving a particular INR range for a specific clinical setting and 54.6% aimed for an INR range of 2.0–3.0 in their patients. A target INR of <2.0 was preferred by 36.4% of the clinicians and above 3.0 by 1.8% of the clinicians.
With reference to the method used in the laboratory to perform a PT test, 45.5% stated it to be manual, 49.1% automated, and 16.7% did not know.
A significant, 45.5% of clinicians, did not instruct their patients what to do if they missed their scheduled dose. However, 60.0% instructed them as to what can happen if they take more than the prescribed dose of the drug.
Only 61.8% instructed patients on action to be taken in case of bleeding episodes while on OAT.
Just over half (50.9%) of the clinicians encountered excessive bleeding while 36.7% listed thrombosis as complications seen in patients on OAT. Of the patients with bleeding, 78.2% clinicians reported seeing minor bleeds and 5.5% clinicians reported major bleeds (requiring transfusion or causing hemodynamic instability) [Table 3].
| Discussion|| |
Oral anticoagulant treatment continues to be an important modality of treatment in several thromboembolic conditions. However, our study has shown significant lacunae in knowledge base among clinicians regarding OAT.
Our study showed that over two-thirds (67.3%) of the clinicians were not aware that different strengths of acitrom, one of the most commonly used anticoagulants, were not color coded. This is a cause for concern as patients have a potential risk of taking the inappropriate dose resulting in OAT related morbidity and mortality.
A study was done by McCormac et al. on the doctor and patient knowledge about oral anticoagulation showed that 90% of the doctors did not have correct knowledge of the dose and the corresponding color of warfarin.
Most (85.5%) clinicians in our study verbally instructed their patients regarding OAT, but only less than one-fifths (18.2%) provided booklets and pamphlets for reference. A study in patients on OAT had shown that 67% of patients received education regarding various aspects of therapy by their doctor.
Another significant finding in our study was that only 56.4% of the clinicians were aware of the correct target range for INR to be achieved in patients. In practice hence, a large number of patients would be in the subtherapeutic window and at risk for thrombosis.
In a study of 181 patients receiving long-term anticoagulation treatment, the primary physician recommended a therapeutic range in 40.8% of patients. The authors noted an overall tendency for under-dosing by physicians.
Specific recommendations exist for the management of patients with nontherapeutic INRs, with INRs above the therapeutic range, with bleeding and whether the INR is in the therapeutic range or elevated.
A study in 572 patients with atrial fibrillation showed that death, cardiac hospitalization, and minor bleeding rates were higher in patients with time in therapeutic range of INR <40% than the group with >40% time in the therapeutic range (P < 0.001).
In a study in 86 adult patients treated with oral anticoagulants, in 41% of the patients, the INR was outside the therapeutic zone while the dosage regimen was too complex in 11% of cases. The authors concluded that OAT-related risks are underestimated by physicians and information given to patients were insufficient or unsuitable.
Another study in 5210 patients with atrial fibrillation on warfarin also showed that patients with renal dysfunction, advanced heart failure, frailty, prior valve surgery, and higher risk for bleeding or stroke had significantly lower time in therapeutic range TTR (P < 0.0001).
Twenty (41.7%) of the clinicians reported that they encounter thrombosis as a complication in patients on OAT while 58.3% of the clinicians in the present study noted bleeding more often. Of the patients with bleeding, 78.2% clinicians reported seeing minor bleeds, and 5.5% reported major bleeds. With oral anticoagulation being used solely for thrombotic conditions, the incidence of thrombosis seen is alarming.
In our study, dietary and drug history was not documented by 85.6% and 50.9% of clinicians, respectively. Over half (56.4%) of the clinicians also did not alert their patients about concomitant alcohol consumption. Food,, alcohol, and other drugs significantly alter the therapeutic action of oral anticoagulants, sometimes with adverse consequences.,
On evaluating the difference in OAT practices between physicians and surgeons, we found that surgeons were more likely to give educational booklets to their patients, document a dietary history and instruct patients regarding concomitant alcohol use in comparison with physicians. A greater percentage of surgeons also instructed their patients regarding management of bleeding after starting OAT than physicians. There was, however, no significant difference among the two groups with regard to patients' awareness on anticoagulant drug effect and the type of complication seen after starting OAT (P = 0.741).
The limitation of our study is that since it is a questionnaire-based study, actual practices by clinicians may be different than those suggested by the findings of the study. A prospective study that audits clinician practices may bring out the actual OAT-related issues.
| Conclusion|| |
Our study has shown significant lacunae in knowledge base among clinicians regarding various aspects of OAT. More emphasis on physician education at all levels is needed for safe OAT in patients.
We would like to thank Dr. Naveen Kakkar, Professor and Head, Department of Hematology, Christian Medical College, Ludhiana for his invaluable support, input and guidance throughout the study.
Financial support and sponsorship
This study was funded by the Department of Clinical Hematology, Hemato-Oncology and Bone Marrow (Stem Cell) Transplant Unit, Christian Medical College and Hospital, Ludhiana.
Conflicts of interest
There are no conflicts of interest.
| References|| |
Blann AD, Landray MJ, Lip GY. ABC of antithrombotic therapy: An overview of antithrombotic therapy. BMJ 2002;325:762-5.
Ansell JE. Oral anticoagulant therapy – 50 years later. Arch Intern Med 1993;153:586-96.
Keeling D, Baglin T, Tait C, Watson H, Perry D, Baglin C, et al.
Guidelines on oral anticoagulation with warfarin – Fourth edition. Br J Haematol 2011;154:311-24.
Harland CC, Walt RP. Warfarin therapy: Need for a protocol? Br J Clin Pract 1988;42:196-7.
Kimmel SE. Warfarin therapy: In need of improvement after all these years. Expert Opin Pharmacother 2008;9:677-86.
McCormack PM, Stinson JC, Hemeryck L, Feely J. Audit of an anticoagulant clinic: Doctor and patient knowledge. Ir Med J 1997;90:192-3.
Schaufele MK, Marciello MA, Burke DT. Dosing practices of physicians for anticoagulation with warfarin during inpatient rehabilitation. Am J Phys Med Rehabil 2000;79:69-74.
Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G; American College of Chest Physicians. Pharmacology and management of the Vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th
edition). Chest 2008;133 6 Suppl: 160S-98S.
Turk UO, Tuncer E, Alioglu E, Yuksel K, Pekel N, Ozpelit E, et al.
Evaluation of the impact of warfarin time in therapeutic range on outcomes of patients with atrial fibrillation in Turkey: Perspectives from the observational, prospective WATER Registry. Cardiol J 2015;22:567-75.
Gras-Champel V, Voyer A, Lematte C, Pakula P, Roussel B, Lefrère JJ, et al.
Assessment of the quality of oral anticoagulation management in patients admitted to Amiens University Hospital. Therapie 2005;60:149-57.
Pokorney SD, Simon DN, Thomas L, Fonarow GC, Kowey PR, Chang P, et al.
Patients' time in therapeutic range on warfarin among US patients with atrial fibrillation: Results from ORBIT-AF registry. Am Heart J 2015;170:141-8.
Harris JE. Interaction of dietary factors with oral anticoagulants: Review and applications. J Am Diet Assoc 1995;95:580-4.
Wittkowsky AK. Dietary supplements, herbs and oral anticoagulants: The nature of the evidence. J Thromb Thrombolysis 2008;25:72-7.
Roth JA, Bradley K, Thummel KE, Veenstra DL, Boudreau D. Alcohol misuse, genetics, and major bleeding among warfarin therapy patients in a community setting. Pharmacoepidemiol Drug Saf 2015;24:619-27.
Wells PS, Holbrook AM, Crowther NR, Hirsh J. Interactions of warfarin with drugs and food. Ann Intern Med 1994;121:676-83.
[Table 1], [Table 2], [Table 3]