Early life risk factors for stroke and cognitive impairment

Cerebrovascular disease may present in later life with stroke or cognitive impairment and dementia, or may be silent, with changes seen incidentally on imaging or pathology. Midlife vascular risk factors such as hypertension, smoking and diabetes are well recognised. However, factors from much earlier in life may contribute to later vascular risk. In this commentary, we outline the importance of considering the whole life course in the development of cerebrovascular disease. We consider mainly factors from childhood, childhood intelligence test scores, education and socioeconomic status, which have been shown to contribute to stroke and cognitive impairment. Factors from even earlier in life, e.g. birth weight and breastfeeding also influence vascular risk factors. We discuss potential mechanisms for the observed relationships, e.g. whether childhood IQ or access to education may influence availability of social and economic resources and adoption of certain lifestyle choices and behaviours which are beneficial to health. Other possible mechanisms behind the observed relationships include differences in brain resilience and integrity reflected in intelligence which may lead to reduced susceptibility to cerebrovascular disease or the ability to sustain a higher degree of pathology before disease becomes clinically evident. Ongoing epidemiological, data linkage, imaging and translational studies are exploring the interrelationships and underlying mechanisms, but meanwhile, it is important to take a life course perspective when considering risk factors for cerebrovascular disease.