Adherence to oral anticoagulant therapy in secondary stroke prevention – impact of the novel oral anticoagulants

Figures & data

Figure 1 Flow chart illustrating the participation of patients who had an OAT installed at discharge from the stroke unit after stroke or transient ischemic attack.

Notes: ^aBy patient or next-of-kin. The rates indicated as % refer to the initial secondary prevention cohort of n=324 patients. To obtain the fatality corrected response rate, we calculated the ratio between completed questionnaires and the number of the entire secondary prevention cohort (n=324) minus the patients that were reported as deceased at 1 year (n=39).
Abbreviation: OAT, oral anticoagulant therapy.

Figure 2 Global neurological function of the patients at 1-year follow-up.

Note: Graded on the modified Rankin Scale score (mRS) according to the written or oral answers of patients and/or their next-of-kin. (A) All participating patients, (B) by mode of participation.

Table 1 Demographic characterization of patients’ anticoagulated with VKA or NOAC at discharge from our stroke units

	VKA at discharge (n=157)	NOAC at discharge (n=167)	P-value
Age (years)	77 (73–83)	76 (71–82)	0.084
Mean, 25%–75% interquartile range
Female sex	49.0%	51.8%	0.658
Hypertension	94.9%	93.5%	0.641
Diabetes mellitus	28.7%	23.2%	0.652
Prior independence	79.6%	81.5%	0.299
NIHSS (median, 25%–75% interquartile range)	2 (1–5)	3 (1–6)	0.191
mRS at discharge (median, 25%–75% interquartile range)	1 (0–2)	1 (0–2)	0.928

Abbreviations: mRS, modified Ranking Scale score; NIHSS, National Institutes of Health Stroke Scale; NOAC, non-VKA oral anticoagulants; VKA, vitamin K antagonists.

Table 2 Persistence to OAT at 1 year by specific choice of OAT at discharge

	VKA (n=157)	Dabigatran (n=112)	Rivaroxaban (n=56)
Patient deceased at 1-year follow-up	17.2% (n=27)	3.6% (n=4)	14.3% (n=8)
Patient lost to follow-up	22.9% (n=36)	25.9% (n=29)	20.0% (n=11)
Patients available for follow-up	60.0% (n=94)	70.5% (n=79)	66.1% (n=37)
VKA at follow-up	80.9%*	8.9%*	11.1%*
Dabigatran at follow-up	5.3%*	70.9%*	0%*
Rivaroxaban at follow-up	7.4%*	11.9%*	83.3%*
Antiplatelets	0%*	8.9%*	0%*
No answer/Other antithrombotic	4.3%*	0%*	2.8%*
No antithrombotic therapy	0%*	0%*	2.8%*
Adherence to any OAT	93.6%*	91.2%*	94.4%*

Notes: Bold fields mark the adherence to the OAT installed at discharge and the adherence to any OAT, both at 1-year follow-up.

* Percentage of patients available at 1-year follow-up.

Abbreviations: OAT, oral anticoagulant therapy; VKA, vitamin K antagonists.

Figure 3 Patients’ self-reported adherence assessed with the MMAS-8.

Notes: Only the patients who had returned the written questionnaire and had filled out the Morisky score at the end of the 1-year follow-up period (n=142) were included in the analysis, excluding patients or next-of-kin who provided their information via telephone interview.
Abbreviations: MMAS-8, eight-point Morisky Medication Adherence Scale; VKA, vitamin K antagonists.

Figure 4 Multivariate analysis of factors influencing adherence to OAT in stroke patients.

Notes: We analyzed all patients with available written or oral questionnaire (n=209) and adjusted for age, sex, mRS at discharge, and at 1-year follow-up and choice of OAT at discharge. *P<0.05.
Abbreviations: CI, confidence interval; DOAC, direct oral anticoagulants; mRS, modified Ranking Scale score; OAT, oral anticoagulant therapy; OR, odds ratio; VKA, vitamin K antagonists.

Table 3 Univariate comparison of patient characteristics between persistent and nonpersistent patients

	Adherent (n=194)	Non-adherent (n=15)	P-value
Age (year) mean, 25%–75% interquartile range	75 (71–81)	76 (73–86)	0.214
Female sex	45.4%	40.0%	0.791
mRS at discharge (median, 25%–75% interquartile range)	1 (0–2)	1 (0–2)	0.616
mRS at 1 year (median, 25%–75% interquartile range)	1 (0–2)	2 (1–3)	0.184
Independence at follow-up	70.4%	36.4%	0.054
VKA prescription§	45.4%	40.0%	0.791
NOAC prescription§	54.6%	60.0%	0.791

Note:

§ At discharge from the stroke units.

Abbreviations: mRS, modified Ranking Scale score; NOAC, non-VKA oral anticoagulants; VKA, vitamin K antagonists.

Table S1 Demographic characterization by specific choice of OAT

	VKA	Dabigatran	Rivaroxaban
Age (years) Mean ± SD	77.4±8.0	74.2±10.4	78.2±8.6
Female sex	49.0%	48.6%	57.1%
Hypertension	94.9%	91.9%	96.4%
Diabetes mellitus	28.7%	18.0%	33.9%
Prior independence	79.6%	83.8%	78.6%
Prior warfarin use	64.3%	11.7%#,***,$,*	30.4%
Serum creatinine level	1.29±0.9 mg/dL	0.9±0.3 mg/dL#,*	1.0±0.4 mg/dL
Mean ± SD	114.0±80.0 µmol/L	79.6±27 µmol/L	88.4±35.4 µmol/L

Notes: Patient characteristics at discharge.

# In comparison to VKA;

$ in comparison to rivaroxaban.

* P<0.05;

*** P<0.001 after Bonferroni correction.

Abbreviations: OAT, oral anticoagulant therapy; SD, standard deviation; VKA, vitamin K antagonists.

Table S2 Reasons to switch therapy during the 1-year follow-up period

	Change from VKA to other treatment n=14 of 85* (16.4%)	Change from dabigatran to other treatment n=22 of 76* (28.9%)	Change from rivaroxaban to other treatment n=4 of 35* (11.4%)
Physician’s concerns	Four patients	Eight patients	One patient
Patient’s concerns	–	–	–
Adverse events	Three patients	Eight patients	One patient
Costs of therapy	–	One patient	One patient
Other	Three patients	Eight patients	One patient
Reasons for medication change as	“Easier use of DOAC” (2×)	“Impaired renal function” (2×)	“Not well tolerated”
detailed by patient or caregiver	“Anemia attributed to VKA”	“Bleeding from gastric ulcers” (2×)
	“Labile INR” (4×)	“Dyspeptic symptoms” (2×)
	“VKA suspected as precipitating factor for psychotic episode”	“Easier use of a once daily regime” (2×)
		“Skin changes attributed to dabigatran”
		“Vertigo attributed to dabigatran”
		“Family doctor: no experience with dabigatran”

Notes:

* Patients available at 1-year follow-up. Patients could provide more than one reason in the questionnaire.

Abbreviations: DOAC, direct oral anticoagulants; INR, international normalized ratio; VKA, vitamin K antagonists.