AJM onlineClinical research studyDoes Statin Therapy Decrease the Risk for Bleeding in Patients Who Are Receiving Warfarin?
Section snippets
Study Design and Data Sources
We used a large linked population-based administrative database in Ontario, Canada, to perform a nested case-control study from April 1, 1994, to March 31, 2002. Prescriptions were identified from the Ontario Drug Benefit Program, which records prescription medications dispensed to residents of Ontario who are age 65 years and older. Hospital admissions for upper gastrointestinal and intracranial bleeding were identified from the Canadian Institute for Health Information Discharge Abstract
Study Subject Characteristics
We identified 79,207 warfarin users with a history of atrial fibrillation, of whom 52% were women. The mean age at cohort entry was 79 years.
Statin Use and Risk for Any Bleeding (Upper Gastrointestinal or Intracranial)
During the period of observation, from April 1, 1994, to March 31, 2002, 1518 individuals from the warfarin cohort were admitted to a hospital with an upper gastrointestinal or intracranial bleed (cases) and were matched to 15,100 controls without a bleeding event (Table 1). Hospital admissions for upper gastrointestinal bleeding (n = 1201) were more common
Discussion
The principal finding of this study is that in warfarin users, long-term statin use seems to be associated with a decreased risk for bleeding complications. However, because new use of a statin does not seem to confer a protective effect against warfarin-associated bleeding, the possibility exists that a protective effect of long-term statin use against bleeding may be related to a “healthy user effect.” Thus, long-term statin users or their physicians may be more attentive to personal health
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Cited by (0)
- 1
Dr. Bell holds a Canadian Institutes of Health Research Phase 2 Clinician-Scientist Award.
- 2
Dr. Mamdani is currently an employee of Pfizer Inc, the manufacturer of one statin. The involvement of Dr. Mamdani in the development of this study and article was preceded by (∼6 months) and was not influenced by his subsequent decision to work for Pfizer.
- 3
Dr. Douketis, Dr. Bell, and Ms. Melo have no conflict of interest or financial disclosures.