Silent- i.e. asymptomatic -brain infarcts are frequently seen on cerebral magnetic resonance imaging (MRl) scans in patients admitted to the hospital with their first stroke. With the increasing use and improvement of imaging techniques, these silent lesions are more often found in people without stroke-like symptoms.' In contrast to symptomatic brain infarcts, the relevance of these so-called silent brain infarcts is not known. Because knowledge of the consequences of silent infarcts is lacking, special treatment regimens have not been developed yet for patients with these lesions. In selected patient groups however, silent brain infarcts seem to increase the risk of stroke and death? Furthermore, hospital-based studies found that they are more frequently present in elderly patients with dementia and depression than in other patients.3 • 4 Prospective longitudinal research in which large groups of asymptomatic people undergo brain imaging is needed to examine the clinical relevance of silent brain infarcts in the general population. In this thesis the following questions are investigated: 1. How frequent are silent brain infarcts in the general population? 2. What are the risk factors for silent brain infarcts? 3. What are the clinical consequences of silent brain infarcts? To answer these questions, data was used from the Rotterdam Scan Study, a large cohort study among elderly people from the general population who underwent MRl scanning of the brain. The presence of (silent) brain infarcts was scored on MRI, as were other brain abnormalities including white matter lesions and global brain atrophy. Both are thought to have a vascular pathogenesis and frequently coexist in ischaemic brains.5·6 In chapter 2, the prevalence and incidence of silent brain infarcts is presented. Furthermore, this chapter describes studies on the risk factors for silent brain infarcts, in which a comparison with the classical risk factors for symptomatic infarcts is made. The investigation of the relationship with one of the relative new risk factors, the potentially modifiable homocysteine, is also reported here. For studies described in chapter 3, this cohort is followed over time and monitored for mortality and major morbidity. This chapter describes the relationship between silent brain infarcts and the risk of three frequent and disabling disorders in elderly people, namely stroke, dementia, and depression. In chapter 4, I discuss and review all findings and make suggestions for further research

Rotterdam Scan Study, epidemiology, neurology, population based study, silent brain infarction
P.J. Koudstaal (Peter) , A. Hofman (Albert)
Erasmus University Rotterdam
The Rotterdam Scan Study was supported by grants from the Netherlands Heart Foundation and the Netherlands Organisation for Scientific Research. Financial support for the study on homocysteine was provided by the EU BIOMED Demonstration Project, whicb paid for the homocysteine assays.
Erasmus MC: University Medical Center Rotterdam

Vermeer, S.E. (2002, October 2). Silent brain infarcts : frequency, risk factors, and prognosis. Erasmus University Rotterdam. Retrieved from