Discontinuation of aspirin therapy within 4 weeks was associated with a significantly increased risk of ischemic stroke or transient ischemic attack (OR 3.4; 95% CI 1.08-10.63; P<.005).
Case-Control (n=618)
Does the discontinuation of aspirin therapy increase the risk of ischemic stroke or transient ischemic attack in patients on long-term aspirin treatment?
Discontinuation of aspirin therapy in the preceding 4 weeks is associated with a 3.4-fold increased risk of ischemic stroke or TIA, emphasizing the critical importance of medication compliance.
Odds Ratio: 3.4 (95% CI 1.08–10.63)
Absolute Event Rate: 4.2% vs 1.3%
p-value: p=<.005
BACKGROUND: Aspirin, or acetylsalicylic acid, is widely used to prevent ischemic vascular disease. Clinical and experimental data suggest that a rebound effect occurs 4 or fewer weeks after interruption of aspirin therapy. OBJECTIVE: To study the discontinuation of aspirin therapy as a risk factor for ischemic stroke (IS). DESIGN: Case-control study. SETTING: Stroke unit. PARTICIPANTS: Three hundred nine patients with IS or transient ischemic attack undergoing long-term aspirin treatment before their index event and 309 age-, sex-, and antiplatelet therapy-matched controls who had not had an IS in the previous 6 months. METHODS: We compared the frequency of aspirin therapy discontinuation during the 4 weeks before an ischemic cerebral event in patients and the 4 weeks before interview in controls. RESULTS: The 2 groups had a similar frequency of risk factors, except for coronary heart disease, which was more frequent in patients (36% vs 18%; P < .001). Aspirin use had been discontinued in 13 patients and 4 controls. Aspirin interruption yielded an odds ratio for IS/transient ischemic attack of 3.4 (95% confidence interval, 1.08-10.63; P < .005) after adjustment in a multivariable model. CONCLUSIONS: These results highlight the importance of aspirin therapy compliance and give an estimate of the risk associated with the discontinuation of aspirin therapy in patients at risk for IS, particularly those with coronary heart disease.
Maulaz et al. (2005) conducted a case-control in Ischemic stroke or transient ischemic attack (n=618). Discontinuation of aspirin therapy vs. Continuation of aspirin therapy was evaluated on Ischemic stroke or transient ischemic attack (OR 3.4, 95% CI 1.08-10.63, p=<.005). Discontinuation of aspirin therapy within 4 weeks was associated with a significantly increased risk of ischemic stroke or transient ischemic attack (OR 3.4; 95% CI 1.08-10.63; P<.005).