Family history in young and middle-aged acute ischemic stroke patients. The Norwegian Stroke in the Young Study

Cardiovascular disease (CVD), including stroke, coronary heart disease (CHD) and peripheral artery disease, is the leading cause of death and disability in the western world. CVD is influenced by genetic and lifestyle factors. Knowledge about heredity is well documented for CHD. However, the influence of a positive family history (FH) on stroke is far less documented. The studies included in this thesis therefore aim to quantify and evaluate a detailed FH of CVD in a young ischemic stroke population with a special regard to sex differences. Further, we aimed to verify the patient reported family history by comparison with parental reports, and to find factors associated with best accuracy of the patient reported FH. In addition we aimed to analyze if a positive FH of CVD is associated with intima-media thickness (IMT) and plaque measurements, performed at standardized sites in the carotid arteries. A total of 59% of our patients reported ischemic CVD events among their first degree family members. Females were three times more likely to report a positive FH than males and knowledge of FH was higher in relatives with a female than male linkage. Detailed knowledge on FH was better for CHD than for stroke. The FH reported from patients were in good concordance with parental reports, but with a slightly decreased accuracy from patients aged over 45 years. FH of stroke was associated with higher internal carotid IMT in young ischemic stroke patients. The association was strong for young patients, and absent in the highest age group from 50-60 years. In conclusion, data presented in this thesis, add new information to the field of young stroke by a detailed FH of CVD and detailed ultrasound diagnostics of the carotid arteries. Thorough diagnostics after ischemic stroke and the history of ischemic CVD events in first degree family members should be basic requirements for future genetic research