Prevalence and Risk Factors of Silent Cerebral Infarction in Apparently Normal Adults

Abstract

Abstract-Cerebrovascular disease is a major cause of death and disability in adults. Silent cerebral infarction (SCI) portends more severe cerebral infarctions or may lead to insidious progressive brain damage resulting in vascular dementia. This study was designed to evaluate the prevalence and risk factors of SCI in an apparently normal adult population. Nine hundred ninety-four consecutive symptom-free adults (mean age 49.0Ϯ7.7; men:women 830:164) who underwent brain magnetic resonance imaging at the Center for Health Promotion at Samsung Medical Center were assessed. All were neurologically normal in history and physical examination. A total of 121 SCI lesions was observed in 58 subjects. The lesion prevalence adjusted for patient age was 5.1%. There was no gender difference in prevalence. Ninety-nine lesions were Ͻ1 cm in diameter, 15 were between 1 and 2 cm, 3 were between 2 and 3 cm, and 4 were Ͼ3 cm in diameter. The most frequent site of the SCI lesion was basal ganglia, after which the periventricular white matter, cerebral cortex, and thalamus were the most frequent sites. Old age, hypertension, a history of coronary artery disease, evidence of cardiomegaly in chest radiographs, and high fasting glucose/hemoglobin A1c levels were associated with SCI on univariate analysis. Multivariate analysis demonstrated old age and hypertension to be independent risk factors for SCI, and mild alcohol consumption was revealed as an independent protective factor against SCI. Key Words: cerebral infarction Ⅲ risk factors Ⅲ hypertension, essential Ⅲ elderly Ⅲ alcohol S ilent cerebral infarction (SCI) is defined as a brain lesion that is presumably a result of vascular occlusion found incidentally by magnetic resonance imaging (MRI) or computed tomography (CT) in otherwise healthy subjects or during autopsy. [1][2][3] It is considered a precursor of symptomatic stroke and progressive brain damage 1-3 that may be associated with vascular dementia.The reported prevalence of SCI has been varied, depending on the study subjects. In studies dealing with symptomatic stroke patients, that prevalence ranged from 10% to 38%. 4,5 A prevalence of 13% was reported in a small population study of normal subjects, 6 and in a study on a large number of elderly subjects, the prevalence was 33% in patients Ն65 years. 7 Because such variance in study subjects has led to different conclusions in regard to the prevalence and risk factors of SCI, 8 -10 we attempted to present a more comprehensive study of SCI in a relatively large population of apparently normal adults of all ages. Methods SubjectsWe studied 994 healthy consecutive subjects who visited the Center for Health Promotion at Samsung Medical Center, Seoul, Korea, from September 1994 through October 1996 and who underwent MRI of the brain as part of their routine health check. Their age ranged from 20 to 78 years; 54 subjects were Ͻ40 years, 572 subjects were between 40 and 49 years, 271 subjects were between 50 and 59 years, 81 subjects were between 60 and 69 years, and 16 subj...

Silent cerebral infarction is associated with the development and progression of nephropathy in patients with type 2 diabetes

“…8,9 SCI is thought to be a clinical end-organ manifestation of arteriosclerosis in the brain, as well as retinal arterial sclerosis in the eyes and renal sclerosis in the kidneys, 10,11 and the presence of SCI predicts incident clinically evident stroke, 12 cardiovascular disease 13 and dementia. 14 SCI has been also shown to be associated with albuminuria in community-dwelling elderly persons 15 and diabetic patients.…”

Risk of “silent stroke” in patients older than 60 years: risk assessment and clinical perspectives

“…In one interesting study, mild alcohol consumption was proven as an independent protective factor for SBI (OR = 0.31; 95% CI: 0.12-0.78). 13 However, this tendency was not valid in those who were older than 50 years. There were some explanations for this protective effect of mild to moderate alcohol consumption.…”

“…The basal ganglia have been the most prevalent location, followed by subcortical white matter, thalamus, cerebral cortex, and infratentorial regions such as cerebellum and brainstem ( Figure 2). 6,8,13,[21][22][23] …”

“…8 Other studies reproduced these results in 175 neurologically healthy elderly who were older than 65 years (OR = 3.54; 95% CI: 1.47-8.59) 33 and in 994 normal healthy adults (OR = 3.47; 95% CI: 1.71-7.03). 13 Another interesting factor was systolic and diastolic BP reactivity related with mental stress. In a previous study that enrolled 67 healthy elderly aged between 55 and 81 years, the relationship between the BP reactivity and SBI was evaluated.…”

“…12 Another study revealed similar prevalence resulting in an age-adjusted SBI prevalence of 5.1% among 994 healthy adults (mean age 49.0 ± 7.7). 13 There were considerable discrepancies in the prevalence rates listed in these studies due to differences in age distribution and the presence of underlying cardiovascular diseases in the study population (Table 1). However, it was evident…”