$438 Thursday, November 10, 2005 Poster Abstracts

1325 The Diurnal variation of Stroke in Maiduguri, North Eastern Nigeria

Salawu, F ~, Bwala, S 2, Bazza, B 3, Sadiq, I ~, Waru, BG 4, KJda, 14, Minoza, K 4, Bani, B 4, Bukbuk, D 4. ZState Specialist Hospital Maiduguri, Nigeria ; ZUniversity of Maiduguri, Maiduguri, Nigeria; 3Federal Medical Centre, Nguru Yobe State, Nigeria; 4University of Maiduguri Teaching Hospital Maidugiri, Nigeria

Background: A diurnal variation in the onset of cardiac events and stroke is well recognized, with the highest incidence occurring during morning hours. These studies have so far been conducted in temperate regions; we are unaware of any published data on diurnal variation of stroke onset in Nigerians. Methods: A prospective observational study in first-ever stroke patients above 18 adnritted to the University of Maiduguri Teaching Hospital between 1 January and 31 December 2002 was carried out. All patients had brain CT. Time of stroke was obtained from relatives or patients themselves when possible. Patients with unknown onset or onset during sleep were excluded. Supine blood pressure measurements were taken on admission using standard mercury sphygmomanometer. Results: Of the 124 stroke patients adnritted, a total of 92 patients were included in the analysis. Sixty-four had a history of hypertension and 28 were normotensives. Seventy-five percent of hypertensive subjects had thromboembolic stroke and 25"/0 had intracerebral haemorrhage (89% and 11%, respectively in normotensive subjects. Most strokes occurred between 6 AM and noon with the pattern being observed for both ischemic and haemorrhagic stroke. Intracerebral haemorrhage occurred less fiequently in the evenings. There was no difference in the time of onset o f stroke between normotensive and treated or untreated hypertensive patients. Conclusion: All types of strokes in Nigerians are most likely to occur after waking in the morning. However, the main drawback of the study was the hospital-based nature which may simply be measuring variation in the likelihood of hospital admission. Further commmrity-based studies in Nigeria and a subsequent meta- analysis are required to determine these relations with certainty.

1326 VISPGEN: a resource for genetic gtudies of Recurrent Ischelnic Stroke

Sale, M M t, Mychaleckyj, JC 1, Hsu, FC ~, Fufie, KL 2, Coull, BM s, Zhong, M 1, Gordon, CJ 1, Gehring, ME 1, Toole, JF 1, Rich, SS 1. ~Wake Forest University School of Medicine, Winston-Salem, U.S.A; 2Massaehusetts General Hospital Boston, U.S.A; 3University of Arizona, Tucson, U.S.A

The Vitanrin Intervention for Stroke Prevention (VISP) Trial assessed whether pharmacological doses of folic acid, vitamins B6 and B12 reduced risk of recurrent cerebral and/or myocardial infarction over a 2-year period. Although there was no difference for ischemic stroke or coronary endpoints by treatment, there was a persistent and graded association between baseline total homocysteine (tHey) level and outcomes. In VISPGEN we are exploring the genetic, determinants of elevated tHey and risk mediated by hyperhomocysteinemia. Results of a mettrionine load test, tHey, folate, and B~2 levels were obtained; baseline levels of Bs, C-reactive protein, yon Willebrand Factor, prothrombin F l+2 , thrombin-antithrombin, tissue plasminogen acti- vator antigen, fibrinogen, and soluble thrombomodulin are being determined. Duplicate burly coat samples were collected fi'om 2,584 out of 3,680 participants at 47 of 56 clinic sites. D N A was extracted using Gentra's Autopure system, with mean yield 5lug (range 0-32lug). Whole genome amplification (WGA) of genomic DNA using the REPLI-g method (Qiagen) produced a mean yield of 537ug (range 279-1,209ug). Using Qiagen's quality metrics, 2,443 samples (95%) were identified as "highly usable" for genotyping assays. A total of 1,536 SNPs have been identified in candidate genes involved in homocysteine and lipid metabolism, coagulation, and inflannnation- for genotyping by Illunrina Custom Services (BeadArray Platform).

W G A DNA will be provided to the National Institute of Neurological Disorders and Stroke (NINDS). Repository as a resource for studies of stroke risk. Studies underway represent the largest investigation to date of genetic contributions to recurrent ischenric stroke.

1327 Transcranial Doppler Waveform blunting in Arteria Cerebri Media and clinical status of the patients with High-Grade Extracranial Carotid Artery Stenosis

Salevi~ Obradovi~ jr, Slankanlenac, p 2 Atsic, D 1, Jotic, S 1, Obradovic, G 1. 2 Medical Center Krusevac, Krusevac, Yugoslavia," 2Institute of Neurology Novi Sad, Novi Sad

Background: Transcranial doppler (TCD) waveform blunting in ipsilateral arteria cerebri media (ACM) in the patients with high- grade (80-99%) stenosis of the extracranial part of the internal carotid artery (AC D is often. It reflects intracranial hemodynamic impairment. The aim of this study was to investigate the frequency of TCD waveform blunting in ACM in our patients with high-grade stenosis of ACI and connection between blunted TCD waveforms of the ACM and clinical status of those patients. Meto as: TCD-s were assessed in 152 patients (mean age 71,8 years, SD 4 years, 36% women) with 80-99% ACI stenosis, detemfinated by Color Duplex sonography. 70 (46%) patients were asymptomatic and 82 (1567,';) were symptomatic., 38 (46?,';) with TIA and 44 (54?,';) with completed stroke. TCD waveform blunting in the ACM was defined as the loss of the systolic peak (reduced systolic flow veleocity and pulsatility). Odds ratio with 95% confidence intervals and X statistics were used. Results: Blunted TCD waveform was found in 64 (178"/o) of the symptomatic and 27 (139%) of the asymptomatic patients. Sympto- matic patients had significantly increaed odds of having blunted TCD waveforms (OR 5,7, 95% CI 2,8-11,5;X ~ - 22,88, d r - 1,p < 0,001). Conclusion: TCD waveform blunting in the ACM may be an additional risk factor for ischemic stroke in the patients with lrigh-grade ICA stenosis.

1328 New risk factors for childhood stroke: a study on 104 patients

Salih, M t, Gader, A 2, AI-Jarallah, A 1 , Kentab, A 1, Alorainy, 13, Hassan, H 3, Bahakim, H 4, Kurban, K 4, Zahraa, j 5 Nasir, A s, Khoja, W s. Division of 1Pediatric Neurology and ¢Hematology, and 5Pediatric Intensive Care Unit Department of Pediatrics; 2Coagulation Laboratory, Department of Physiology; 3Department of Radiology, College of Medicine, King Saud University; eDepartment of Neurology, Armed Forces Hospital Riyadh, Saudi Arabia

During prospective and retrospective study periods of 10 years and 7 months, 117 children (61 males and 56 males) with stroke were evaluated for underlying risk factors. The majority (89?,'o) of patients were Saudis. The mean age at onset of the initial stroke was 27 (SD -- 9.3) months and median was 6 months. A major risk factor was identified in 93 of these 10a (89.4%). Hematologic disorders was the most common risk factor (46.2%): prothrombic disorders, 31.7%; sickle cell disease (SCD) and SC[3°-thalassemia, 11.5%; and coagula- tion defect (all had factor IX deficiency), 2.9%. The presence of anticardiolipin antibodies (113/49, 27?,'o) was the most frequent abnormality. Congenital and genetic cerebrovascalar anomalies were the underlying cause in 7 patients (6.7%) and cardiac diseases in 6 (5.8%). Six patients (5.8%) had moyamoya syndrome which was associated with another disease as follows: SCD, S[3 ° - thalassemia and membranous ventricular septal defect; protein C deficiency, protein S deficiency, wrinkly skin syndrome (),VSS, OMIM 278250), and Adams- Oliver syndrome (AOS, OMIM 100300). The association of moya- moya syndrome and protein C deficiency was first reported in tiffs cohort of patients, whereas the association of the syndrome with WSS and AOS has not, hitherto, been described. Three patients who had