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Warfarin for AF in long-term care


Clinical bottom line

In older patients in long-term residential care in Connecticut, anticoagulants were under used, even in ideal candidates. Substantial opportunities exist to improve healthcare provision for these patients.


D McCormick et al. Prevalence and quality of warfarin use for patients with atrial fibrillation in the long-term care setting. Archives of Internal medicine 2001 161: 2458-2463.


Patients in 21 long-term care centres in Connecticut formed the population for the study. Medical records of each resident was reviewed by a trained nurse for possible inclusion. A diagnosis of atrial fibrillation (AF) during the study period with electrocardiographic diagnosis was a condition for inclusion, with no discrimination between rheumatic or non rheumatic AF. Exclusions were those with length of stay of 30 days or less or with rend stage renal disease.

Clinical information was collected on patients with AF, including comorbid conditions, risk factors for haemorrhage, treatments, and INR values if recorded.


Just under 3000 records were reviewed, with AF present in 429 (17%) of the 2600 patients eligible for the study. The mean age was 87 years (range 60 to 107), and most were women. Risk factors for stroke were present in 93%, and for bleeding in 80%.


During the 12 months of observations, 180 of the 429 patients received warfarin for at least two weeks (42%). Of those not receiving warfarin, 136 neither received aspirin. Half of 83 ideal candidates for warfarin therapy did not receive it, and a quarter of those with stroke risk factors without bleeding risk factors received neither warfarin nor aspirin.


Of the 180 patients receiving warfarin, 6 (3%) had no recorded INR data. INRs were measured with intervals of at least seven days for 45%, 8 to 30 days for 45% and more than 30 days for 5%. Values in the therapeutic range were achieved 50% of the time.


This naturalistic study was commendable because it looked at every patient in 21 Connecticut nursing homes so that results were comprehensive. It found undertreatment with anticoagulants in older people in long term care. It has a useful discussion on previous studies. Substantial opportunities exist to improve anticoagulation in these patients.