[Levels of INR in patients admitted to the department of internal medicine].

We reviewed the records of 282 patients admitted to the Department of Internal Medicine who had been treated at home with warfarin. In 181 patients INR was measured on the day of admission. Less than 20% of the 44 patients treated with warfarin for artificial valves had INR levels within the therapeutic range--3-4. Among the 138 patients treated with warfarin for atrial fibrillation only 31.9 were in the therapeutic range of 2-3. Seven patients in the atrial fibrillation group had very high values of INR--above 7. These patients were older (mean age 82 years) compared to 69.4 years in the rest of the group. Four patients with INR's above 7 had mild hemorrhagic events. Our data show that most patients treated with warfarin were not in the therapeutic range.