Neurology -- Correspondence for Sanossian et al., 66 (3) 319-323

Correspondence published:

Premorbid antiplatelet use and ischemic stroke outcomes: Hai-feng Li, Xu-dong Pan (9 May 2006)

Reply from the authors: Nerses Sanossian, Bruce Ovbiagele (9 May 2006)

Premorbid antiplatelet use and ischemic stroke outcomes 9 May 2006

Hai-feng Li,
Department of Neurology, Affiliated Hospital of Medical College, Qingdao University
No. 16, Jiangsu Road, Qindao, Shandong Province, China, 266003,
Xu-dong Pan
Send Correspondence to journal:
Re: Premorbid antiplatelet use and ischemic stroke outcomes

drlhf{at}163.com Hai-feng Li, et al.

We are intrigued by this additional evidence on the protective effect of premorbid antiplatelet use in stroke patients reported by Sanossian et al. [1]
Although the study showed that premorbid antiplatelet drugs had a protective effect on short-term outcome, the authors did not provide sufficient background to analyze this effect. Rankin score was assessed at discharge but this is a vague time-point. It was recently shown that some stroke patients had functional deterioration after early recovery [2] and the highest risk of occurrence of stroke after TIA or minor stroke is within the first several days. [3] If the time to assess Rankin score is too early, a confounding effect is unclear due to the subgroup of unstable patients.
In addition, any medications used after stroke were not mentioned in the article. Statin use within four weeks after stroke is found to be associated with a favorable outcome at 12 weeks. [4] Another study of premorbid aspirin use on stroke severity found there was no interaction between danaparoid/placebo treatment and aspirin use. [5]
Although baseline NIHSS score may predict outcome in the placebo group as cited in this article, we cannot make the same assumption in the treatment group. Moreover, the authors did not explain the relationship between NIHSS score at onset and Rankin score at discharge. They did not report NIHSS scores at discharge. In the other study, [5] although there was categorization according to baseline and 3-month NIHSS scores, the authors did not explain the relationship between severity at onset and outcome either. We are more interested in whether a milder impact at onset in the premorbid group is associated with better outcome once it has occurred.
Although the study showed premorbid antiplatelet use was not associated with less severity at onset in those with a prior history of stroke or TIA, the authors failed to show the results of the subgroup with recent stroke or TIA history. This subgroup is unstable, with more risk of worse outcome or recurrence in short term. [2,3] Although prior ischemic history may mask the effects of premorbid use of antiplatelet drugs by collateral compensation and preconditioning, the subgroup with recent ischemic events might give a good chance to find the protective effect of premorbid treatment. If premorbid antiplatelet use in patients with recent ischemic events results in better outcome, it may justify an aggressive use in these unstable patients.
References
1. Sanossian N, Saver JL, Rajajee V, et al. Premorbid antiplatelet use and ischemic stroke outcomes. Neurology 2006;66:319-323.
2. Johnston SC, Leira EC, Hansen MD, Adams HP Jr. Early recovery after cerebral ischemia risk of subsequent neurological deterioration. Ann Neurol 2003;54: 439-444.
3. Rothwell PM, Warlow CP. Timing of TIAs preceding stroke: time window for prevention is very short. Neurology 2005;64:817-820.
4. Moonis M, Kane K, Schwiderski U, Sandage BW, Fisher M. HMG-CoA reductase inhibitors improve acute ischemic stroke outcome. Stroke 2005;36:1298-300.
5. Wilterdink JL, Bendixen B, Adams HP Jr, Woolson RF, Clarke WR, Hansen MD. Effect of prior aspirin use on stroke severity in the trial of Org 10172 in acute stroke treatment (TOAST). Stroke 2001;32:2836-2840.
The authors report no conflicts of interest.

Reply from the authors 9 May 2006

Nerses Sanossian,
UCLA Stroke Center
710 Westwood Plaza Los Angeles, CA 90095,
Bruce Ovbiagele
Send Correspondence to journal:
Re: Reply from the authors

nsanossian{at}mednet.ucla.edu Nerses Sanossian, et al.

We thank Drs. Li and Pan for their interest in our article. We disagree with their categorization of the discharge Rankin score as a �vague time-point�. Despite early deterioration observed in some stroke patients, hospital discharge functional outcome remains a useful endpoint for short-term assessment after stroke as evidenced by studies which have and continue to measure it [1-4] including a recent study in which the lead author of one of the papers cited by Drs Li and Pan was involved. [5]
With regard to medications used after the index stroke, the overwhelming majority of patients admitted to our stroke unit are started on statins within 24 hours [6] but we must point out that beyond observational studies, we are unaware of any prospective randomized controlled clinical trial that has shown a favorable short-term benefit for statins after acute stroke.
Data were not collected on the exact dates of prior cerebrovascular events within our study and it is conceivable that some patients may have experienced recent events. However, we suspect that these patients were a considerable minority. Finally, as noted in the discussion section, our study was limited by its observational nature and the most effective means of testing the hypothesis generated by it would be to include stroke severity measures in prospective clinical trials of antiplatelet agents.
References
6. Qureshi AI, Kirmani JF, Sayed MA, et al. Buffalo Metropolitan Area and Erie County Stroke Study Group.Time to hospital arrival, use of thrombolytics, and in- hospital outcomes in ischemic stroke. Neurology 2005;64:2115-2120.
7. Smith MA, Lisabeth LD, Brown DL, Morgenstern LB. Gender comparisons of diagnostic evaluation for ischemic stroke patients. Neurology 2005;65:855-858.
8. Jacobs BS, Birbeck G, Mullard AJ, et al. Quality of hospital care in African American and white patients with ischemic stroke and TIA. Neurology 2006;66:809-814.
9. Matz K, Keresztes K, Tatschl C, et al. Disorders of glucose metabolism in acute stroke patients: an underrecognized problem. Diabetes Care. 2006;29:792-797.
10. Smith WS, Tsao JW, Billings ME, et al. Prognostic significance of angiographically confirmed large vessel intracranial occlusion in patients presenting with acute brain ischemia. Neurocrit Care 2006;4:14-17.
11. Ovbiagele B, Saver JL, Fredieu A, et al. PROTECT: a coordinated stroke treatment program to prevent recurrent thromboembolic events. Neurology 2004;63:1217-1222.
The authors report no conflicts of interest.