Bleeding complications during warfarin treatment in primary healthcare centres compared with anticoagulation clinics

Figures & data

Figure 1.  Cox regression analysis showing proportion free from major bleeding and fatal bleeding. Dotted lines denote specialized anticoagulation clinics and closed lines denote primary healthcare units.

Table I.  Baseline characteristics for patients monitored at specialized anticoagulant clinics and primary healthcare units.

	Specialized anticoagulation clinics	Primary healthcare units	p-value
Age, means (SD)	66.6 (12.7)	71.4 (11.0)	<0.001
Females, (%)	634 (41.2)	518 (43.4)	0.26
Indication: number of patients (%)
Heart valve prosthesis	254 (16.5)	152 (12.7)	0.006
Venous thromboembolism	470 (30.6)	313 (26.2)	0.012
Atrial fibrillation with cerebral emboli	192 (12.5)	260 (21.8)	<0.001
Atrial fibrillation with peripheral emboli	10 (0.7)	31 (2.6)	<0.001
Atrial fibrillation (no emboli)	266 (17.3)	125 (10.5)	<0.001
Heart disease (other)	123 (8.0)	29 (2.4)	<0.001
Ischemic cerebrovascular disease	140 (9.1)	169 (14.2)	<0.001
Peripheral vascular disease	32 (2.1)	13 (1.1)	0.043
Miscellaneous	50 (3.3)	102 (8.5)	<0.001

Means, standard deviation (SD), numbers, and frequencies within the monitoring sites are given. p-values were calculated with t-test or chi-squared test.

Figure 2.  Risk of major or fatal bleeding per 100 treatment years for different age categories.

Table II.  Multivariate Cox regression analysis of possible determinants of bleeding (114 events) in the Sundsvall subgroup (n = 1579).

Determinant	Odds ratio (95% CI)
History of diabetes (n = 313)	0.80 (0.50–1.30)
History of hypertension (n = 523)	1.06 (0.72–1.56)
History of cancer (n = 113)	1.53 (0.84–2.80)
History of peptic ulcer disease (n = 58)	3.44 (1.91–6.17)
Gender	0.89 (0.61–1.30)
Age (increase per year)	1.05 (1.03–1.08)

Odds ratios and 95% confidence intervals are shown.

Table III.  Frequencies of major and fatal bleeding according to indications for oral anticoagulation.

Indication	Major bleeding			Fatal bleeding
	Patients	Treatment years	Number (%)	Treatment years	Number (%)
Heart valve prosthesis	406	1083	41 (3.8)	1141	8 (0.70)
Venous thromboembolism	783	845	44 (5.2)	872	6 (0.68)
Atrial fibrillation with cerebral emboli	452	1068	41 (3.8)	1092	8 (0.73)
Atrial fibrillation with peripheral emboli	41	107	8 (7.4)	110	2 (1.81)
Atrial fibrillation (no emboli)	391	632	20 (3.2)	640	4 (0.62)
Heart disease (other)	152	140	6 (4.3)	142	0
Ischaemic cerebrovascular disease	309	683	21 (3.2)	692	4 (0.64)
Peripheral vascular disease	45	77	6 (7.8)	84	1 (1.19)
Miscellaneous	152	260	8 (3.1)	270	1 (0.37)

Table IV.  Site of major and fatal bleeding events.

Bleeding event	Major	Fatal
Gastrointestinal haemorrhage	72	4
Intracerebral haemorrhage	37	21
Epistaxis	17	0
Haematuria	18	0
Abdominal aortic aneurysm	8	7
Other	43	2