April 28, 2010 — 根據一篇由西班牙研究團隊進行的文獻回顧,查加斯氏疾病,一種由寄生蟲Trypanosoma cruzi造成的疾病,是缺血性中風一個獨立危險因子,且許多病患並不知道他們被感染了,直到他們發生中風。
西班牙巴塞隆納昆卡Virgen de la Luz醫院的Francisco Javier Carod-Artal醫師與醫院診所的Joaquim Gascon醫師引用一項研究,其中高達42%罹患查加斯氏疾病患者持續有缺血性中風,且在中風後才診斷遭到感染(J Neurol Sci. 2007;263:35-39)。
Parasitic Chagas Disease a Growing Cause of Ischemic Stroke
By Pam Harrison
Medscape Medical News
April 28, 2010 — Chagas disease, caused by the parasite Trypanosoma cruzi, is an independent risk factor for ischemic stroke, and many patients are unaware they are infected until after they have their first stroke, according to a new review of the literature by Spanish investigators.
Francisco Javier Carod-Artal, MD, Hospital Virgen de la Luz, Cuenca, and Joaquim Gascon, MD, Hospital Clinic, Barcelona, Spain, cite 1 study in which 42% of patients with Chagas disease who had sustained an ischemic stroke were diagnosed with the infection after they had had their stroke (J Neurol Sci. 2007;263:35-39).
"Few data are available on the cumulative risk of stroke in people with T cruzi infection," they note. The review is published online April 14 and will appear in the May issue of The Lancet Neurology.
Screen Stroke Patients
In 1 cohort of patients with mild chagasic cardiomyopathy, approximately 1.2% of patients had an ischemic stroke during the first year of follow-up (Acta Cardiol. 2000;55:33-38). At a mean follow-up of 36 months, another group of 213 patients with Chagas disease and left ventricular systolic dysfunction showed an overall incidence of ischemic stroke of 2.7 events per 100 patient-years (J Neurol Sci. 2009;278:96-101).
"Stroke could be the first sign of Chagas disease in patients with asymptomatic or chronic disease, irrespective of systolic dysfunction or presence of cardiac arrhythmias," the study authors add, "and patients with Chagas disease but without associated vascular risk factors or clinical evidence of heart failure could also be at risk of stroke."
In light of this, stroke patients should be screened for T cruzi infection if they reside in or have emigrated from endemic regions, the study authors suggest.
Chagasic Cardiomyopathy
Chagasic cardiomyopathy is independently associated with ischemic stroke, the study authors point out, and is characterized by the presence of congestive heart failure, several types of arrhythmias, conduction defects, sudden cardiac death, and systemic thromboembolism.
"The main risk factors associated with chagasic stroke include cardiac apical aneurysm, arrhythmias, mural thrombus, and left ventricular dysfunction," they add, whereas about 70% of patients with chagasic stroke have electrocardiographic abnormalities.
In contrast, classic risk factors, such as hypertension, diabetes, and smoking, are less common in stroke patients with Chagas disease than in those without, at least according to 1 cross-sectional study (J Neurol Neurosurg Psychiatry. 2003;74:516-518).
"No specific signs or neurological symptoms can distinguish chagasic stroke from other causes of cardioembolic stroke," the study authors note. In stroke patients with T cruzi infection, treatment of acute stroke and secondary prevention measures should be done according to stroke guidelines, they add.
It is estimated that stroke recurrence occurs in approximately 20% of patients and secondary prevention measures include long-term anticoagulation in cardioembolic chagasic stroke. "Clinical trials are needed to assess the efficacy of long-term oral anticoagulation in primary and secondary prevention of stroke in Chagas disease," they conclude.
Finally, the association among Chagas disease, stroke, and the risk for vascular dementia has not been "properly investigated," they add, and there are no studies assessing the effect of recurrent chagasic infection on vascular dementia. "Although some studies have reported an association between chronic T cruzi infection and cognitive impairment, as measured by the Mini-Mental State Examination, further studies are needed to prove this link."
Changes in migration patterns, including emigration from Latin America, could lead to a substantial disease burden from T cruzi infection in the United States and in Europe, the study authors predict.
The study authors have disclosed no financial relationships.