Knowledge of vitamin K antagonists’ use in atrial fibrillation patients
More details
Hide details
Katedra i Klinika Chorób Wewnętrznych Uniwersytetu Medycznego w Lublinie; Oddział Kardiologii – Pododdział Intensywnego Nadzoru Kardiologicznego, Wojewódzki Szpital Specjalistyczny w Lublinie
Oddział Kardiologii – Pododdział Intensywnego Nadzoru Kardiologicznego, Wojewódzki Szpital Specjalistyczny w Lublinie
Katedra i Klinika Chorób Wewnętrznych Uniwersytetu Medycznego w Lublinie
Corresponding author
Daria Gorczyca-Siudak   

Katedra i Klinika Chorób Wewnętrznych Uniwersytetu Medycznego w Lublinie, SPSK 1, ul. Staszica 16; Lublin
Med Og Nauk Zdr. 2016;22(1):33-39
Vitamin K antagonists (VKA) are a well-known group of antithrombotic agents examined in clinical trials with a proven effect of preventing embolic complications in patients with atrial fibrillation (AF). In order to achieve such an efficacy and safety, it is essential to educate the patients and maintain their strict compliance.

To examine the level of knowledge about thromboembolism prevention in patients with AF who receive oral anticoagulants – acenocumarol, warfarin – and to assess the regularity of taking the oral anticoagulant and the value of INR as a measure of the effectiveness of the therapy.

Material and Methods:
The prospective trial included 55 randomly chosen patients asked to fill out a questionnaire created for the purposes of the study. The value of INR at admission was also collected.

Among 55 examined patients, just over a half had the feeling of sufficient knowledge about the drug. Mean test result was 5.76 points out of a possible 13. Only every other patient received written materials regarding the rules of the treatment. The INR value in the therapeutic range was noted in 56.4% of patients. The correct limits of that range were given by only 45.5%.

The level of patients` knowledge about the rules of the therapy with VKA is low. It correlates negatively with age. Older patients require special attention of the physician starting the therapy, a longer time for education, or a more meticulous monitoring of the treatment. Receiving materials about the VKA and INR leads to an increase in patients` knowledge. A better knowledge about the rules of the treatment does not mean keeping the INR value within the therapeutic range. However, it allows patients to participate in the drug dose adjustment.

Pruszczyk P, Stępińska J, Banasiak W, Członkowska A, Opolski G, Niewada M, i wsp. Zastosowanie nowych doustnych leków przeciw-krzepliwych w prewencji powikłań zatorowych u chorych z migotaniem przedsionków. Kardiol Pol. 2012; 70(9): 979–988.
Miyasaka Y, Barnes ME, Gersh BJ, Cha SS, Bailey KR, Abhayaratna WP i wsp. Secular trends in incidence of atrial fibrillation in Olmsted County, Minnesota, 1980–2000, and implications on the projections for future prevalence. Circulation. 2006; 114(2): 119–125.
Camm AJ, Lip GYH, De Caterina R, Savelieva I, Atar D, Hohnloser SH i wsp. 2012 focused update of the ESC guidelines for the management of atrial fibrillation. Eur Heart J. 2012; 33: 2719–2747.
de Felipe Medina R. Level of understanding of patients on anticoagulans at a health centre: relationship of this and monitoring of therapy. Aten Primaria. 2003; 32(2): 101–105.
Völler H, Dovifat C, Glatz J, Körtke H, Taborski U, Wegscheider K. Self management of oral anticoagulation with the IN Ratio system: impact of a structured teaching program on patient›s knowledge of medical background and procedures. Eur J Cardiovasc Prev Rehabil. 2004; 11(5): 442–447.
Tang EO, Lai CS, Lee KK, Wong RS, Cheng G, Chan TY. Relationship between patients’ warfarin knowledge and anticoagulation control. Ann Pharmacother. 2003; 37(1): 34–39.
Lee VW, Tam CS, Yan BP, Man Yu C, Yin Lam Y. Barriers to warfarin use for stroke prevention in patients with atrial fibrillation in Hong Kong. Clin Cardiol. 2013; 36(3): 166–171.
Davis NJ, Billett HH, Cohen HW, Arnsten JH. Impact of adherence, knowledge, and quality of life on anticoagulation control. Ann Phar-macother. 2005; 39(4): 632–636.
Hu A, Chow CM, Dao D, Errett L, Keith M. Factors influencing patient knowledge of warfarin therapy after mechanical heart valve replace-ment. J Cardiovasc Nurs. 2006; 21(3): 169–175.
Sawicka-Powierza J, Ołtarzewska AM, Chlabicz S. Knowledge of patients undergoing long-term acenocumarol treatment about the safety of anticoagulant therapy. Pol Merkur Lek. 2007; 22(127): 36–40.
Sawicka-Powierza J, Ołtarzewska AM, Chlabicz S i wsp. Educational role of community nurse in care of patients treated with oral anticoagulation therapy. Pol Merkur Lek. 2009 Jun; 26(156): 636–9.
Baker JW, Pierce KL, Ryals CA. INR goal attainment and oral antico¬agulation knowledge of patients enrolled in an anticoagulation clinic in a Veterans Affairs medical center. J Manag Care Pharm. 2011; 17(2): 133–142.
Kim JH, Kim GS, Kim EJ, Park S, Chung N, Chu SH. Factors affecting medication adherence and anticoagulation control in Korean patients taking warfarin. J Cardiovasc Nurs. 2011; 26(6): 466–474.
Sawicki PT. A structured teaching and self-management program for patients receiving oral anticoagulation: a randomized controlled trial. Working Group for the Study of Patient Self-Management of Oral Anticoagulation. JAMA. 1999; 281(2): 145–150.
Vormfelde SV, Abed MA, Hua TD, Schneider S, Friede T, Chenot JF. Educating Orally Anticoagulated Patients in Drug Safety: A Cluster-Randomized Study in General Practice. Dtsch Arztebl Int. 2014; 111(37): 607–614.
Van Berkel MA, Crannage AJ, Murphy JA. Evaluation of education on the appropriate use of vitamin k in warfarin reversal in adult inpatients. Hosp Pharm. 2013; 48(8): 662–667.
Hansten PD, Horn JR. Hansten and Horn’s drug interactions analysis and management. Vancouver: Applied Therapeutics; 1997: 7–8.
Hylek EM, Heiman H, Skates SJ, Sheehan MA, Singer DE. Acetami¬nophen and other risk factors for excessive warfarin anticoagulation. JAMA. 1998; 279(9): 657–662.
Chan TY. Adverse interactions between warfarin and nonsteroidal antiinflammatory drugs: mechanisms, clinical significance, and avoi-dance. Ann Pharmacother. 1995; 29(12): 1274–1283.
Turpie AG, Gent M, Laupacis A, Latour Y, Gunstensen J, Basile F i wsp. A comparison of aspirin with placebo in patients treated with warfarin after heart-valve replacement. N Engl J Med. 1993; 329(8): 524–529.
Stępińska J, Poniatowska E, Ablewska U, Abramczuk E. Jak bezpiecznie i skutecznie stosować leki przeciwzakrzepowe? Poradnik dla pacjentów. Wyd. 4. Warszawa: Klinika Wad Nabytych Instytutu Kardiologii w Warszawie; 2010.
Buckley NA, Dawson AH. Drug interactions with warfarin. Med J Aust 1992; 157(7): 479–483.
Mukamal KJ, Smith CC, Karlamangla AS, Moore AA. Moderate alcohol consumption and safety of lovastatin and warfarin among men: the post-coronary artery bypass graft trial. Am J Med. 2006; 119(5): 434–440.
Journals System - logo
Scroll to top