Adherence to guidelines for the prescribing of double and triple combinations of antithrombotic agents.
BACKGROUND
To prevent cardiovascular complications, sometimes double and triple therapy with a vitamin K antagonist (VKA), clopidogrel and/or acetylsalicylic acid (ASA) are indicated. These combinations increase the patient's risk of serious bleeding events. Therefore, adherence to clinical guidelines is of the utmost importance when these high-risk therapies are prescribed.


METHODS
We performed a retrospective cohort study of 238 cases in a community pharmacy that were treated with a combination of VKA, clopidogrel and/or ASA between January 2006 and December 2009. Hospital records and community pharmacy records were used to obtain the indication(s), the duration of combination therapy, the presence of risk-increasing and risk-decreasing co-medications and any relevant co-morbidities. The cardiologists' attitudes towards the prescribing of antithrombotic combinations and their self-reported adherence to guidelines were assessed by a brief questionnaire.


RESULTS
We found there was no guideline-based indication for 22 of the 146 cases (14%) on ASA plus clopidogrel and 19 of the 82 cases (23%) on VKA plus ASA. Of the 238 cases given antithrombotic combination therapies, 77 (32%) were placed at an additional increased risk of serious gastrointestinal events, yet 43 (56%) of these did not receive adequate gastric protection. Out of the 19 of 60 cardiologists (32%) who responded to our questionnaire; 17 (90%) and 13 (68%) stated that a strict indication is very important when initiating therapy with ASA plus clopidogrel or ASA plus VKA, respectively.


CONCLUSIONS
There is room to further develop adherence to guideline-based prescribing of antithrombotic combination therapies and to improve prescription of gastric protection for patients receiving these high-risk combinations.
IQ Healthcare, Nijmegen, The Netherlands.
Margaretha F
MF
Warlé-Van Herwaarden
Monique
M
Roukens
Gheorghe A M
GA
Pop
Evert J P
EJ
Lamfers
Peter A G M
PA
De Smet
Cornelis
C
Kramers
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000627:therapeutic use; D001291:Attitude of Health Personnel; D000077144:Clopidogrel; D003157:Community Pharmacy Services; D015897:Comorbidity; D004347:Drug Interactions; D011307:Drug Prescriptions; D004359:Drug Therapy, Combination; D017723:Drug Utilization Review / Q000639:trends; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D019983:Guideline Adherence / Q000639:trends*; D019538:Health Care Surveys; D007722:Health Knowledge, Attitudes, Practice; D006470:Hemorrhage / Q000139:chemically induced / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians' / Q000639:trends*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013988:Ticlopidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D014812:Vitamin K / Q000037:antagonists & inhibitors
D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D014812:Vitamin K; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin