Evaluation of Anticoagulation Control among Patients Taking Warfarin in University of Gondar Hospital, Northwest Ethiopia

Table 3

Bivariate and multivariate logistic regression analyses of time spent within the therapeutic INR range (TTR) among patients taking warfarin in University of Gondar, Northwest Ethiopia, from November 1, 2019, to October 31, 2020 (n = 338).

Variables	TTR		COR (CI)	value	AOR (CI)	value
	TTR < 65%	TTR ≥ 65%
Age
<40 years	100	15	1.04 (0.48, 2.27)	0.922
40–60 years	97	13	0.94 (0.42, 2.12)	0.877
>60 years	99	14	1
Gender
Male	103	18	1
Female	193	24	1.41 (0.73, 2.71)	0.310
Marital status
Single	50	11	1
Married	218	28	1.98 (0.51, 7.71)	0.325
Others	27	3	1.15 (0.33, 4.04)	0.825
Monthly income
<1500 birr	157	26	1
1500–3000 birr	77	8	1.28 (0.55, 2.99)	0.563
>3000 birr	62	8	0.81 (0.29, 2.27)	0.682
Educational level
Cannot read and write	61	10	1
Informal education	91	12	1.80 (0.53, 6.12)	0.345
Elementary school	45	6	1.45 (0.44, 4.76)	0.539
Secondary school	54	10	1.47 (0.39, 5.56)	0.573
College and above	44	4	2.04 (0.60, 6.94)	0.255
Residence
Urban	170	23	0.89 (0.47, 1.72)	0.744
Rural	126	19	1
BMI (kg/m^2)
<18.5	25	4	1
18.5–24.9	199	30	1.44 (0.39, 5.19)	0.578
≥25	72	8	1.36 (0.59, 3.09)	0.469
Indication for warfarin
Atrial fibrillation	222	30	1
VTE	64	8	0.14 (0.02, 0.99)	0.049	0.56 (0.14, 2.18)	0.404
Others	10	4	0.31 (0.08, 1.23)	0.097	0.43 (0.09, 1.94)	0.271
Dose of warfarin
<5 mg daily	181	18	1
5 mg daily	98	20	0.39 (0.12, 1.32)	0.133	0.40 (0.09, 1.64)	0.282
>5 mg daily	17	4	0.91 (0.28, 2.98)	0.877	0.94 (0.24, 3.74)	0.950
Nonadherence to warfarin
Yes	40	2	1
No	266	30	2.26 (0.52, 9.81)	0.278
Concomitant drugs use
Yes	268	37	1
No	28	5	1,29 (0.47, 3.56)	0.618
Frequency of INR monitoring
Every 2 weeks	28	4	0.68 (0.15, 3.05)	0.613
Every 1 month	249	34	0.65 (0.21, 2.02)	0.455
Every 2 months	19	4	1
Alcohol intake
Yes	54	6	1
No	241	36	1.34 (0.54, 3.34)	0.531
Chronic liver disease
Yes	14	3	0.91 (0.46, 1.80)	0.791
No	122	16	1
Unknown	160	23	1.49 (0.39, 5.59)	0.554
Chronic kidney disease
Yes	25	4	1.32 (0.62, 2.85)	0.473
No	184	28	1
Unknown	87	10	1.39 (0.40, 4.82)	0.602
Heart failure
Yes	130	14	1
No	166	28	0.64 (0.32, 1.26)	0.197	1.70 (0.80, 3.61)	0.168
Hyperthyroidism
Yes	45	6	1
No	251	36	0.93 (0.37, 2.33)	0.877

BMI, body mass index; VTE, venous thromboembolism; concomitant drugs use included antiplatelets, statins, antihypertensives, antithyroid drugs, and antiretroviral drugs.