Predictors of bleeding risk in patients with high international normalized ratio (INR) values in warfar in therapy / 中华全科医师杂志

ABSTRACT

Objective:To investigate the risk factors of bleeding events in patients with high international normalized ratio (INR) values (INR>3.5) in warfarin therapy.Methods:Two hundred and one patients with high INR values (INR>3.5) during warfarin therapy admitted in Beijing Tongren Hospital from August 2013 to August 2019 were enrolled. The bleeding occurred in 75 patients (bleeding group) and did not occur in 126 cases (non-bleeding group) during hospitalization. The bleeding group included 12 major bleeding patients and 63 minor bleeding patients. The baseline information, laboratory results and medication of other drugs were recorded.Results:There were no significant differences in age, sex, smoking history, drinking history, previous bleeding history and the proportion of first application of warfarin between the two groups ( P>0.05).The proportion of patients with liver dysfunction [7.14%(9/126)], renal dysfunction [11.90%(15/126)], anemia [4.76%(6/126)], hypoproteinemia [4.76%(6/126)], infectious diseases [20.63%(26/126)] in non-bleeding group were significantly lower than that in bleeding group [16.00% (12/75), 32.00% (24/75), 29.33%(22/75), 16.00%(12/75), 44.00%(33/75); χ 2=3.942, 12.140, 23.675, 7.283, 12.377, respectively; all P<0.05]. A total of 54 kinds of drugs were associated with the INR elevation. The most commonly used drugs were cardiovascular system drugs ( n=162, 80.60%), blood system drugs ( n=155, 77.11%), anti-infective drugs ( n=112, 55.72%), digestive system drugs ( n=82, 40.80%), and endocrine system drugs ( n=56, 27.86%). The INR values [4.58(3.94, 5.90), 4.96(4.03, 8.27)] and the HAS-BLED scores [3.00 (2.00,3.00), 3.00(2.25,3.00)] in minor bleeding group ( n=63) and major bleeding group ( n=12) were higher than those in non-bleeding group [4.00(3.74, 4.35), 2.00 (1.00,3.00), P<0.01), but there was no significant difference in INR values and HAS-BLED scores between minor bleeding group and major bleeding group ( P>0.05). Conclusion:There are many factors leading to the increase of INR in patients taking warfarin, such as abnormal liver and kidney function, anemia, hypoproteinemia, and the use of antibacterial drugs. It is necessary to be cautious about co-administration in these patients.