BDNF and transient ischemic attack: More recently, as part of the Framingham Study, high serum BDNF levels were associated with lower levels of WHM in individuals free from stroke or transient ischemic attack, and after 10-year follow-up, lower serum BDNF was associated with increased risk of incident stroke and transient ischemic attack, suggesting that BDNF levels may modify the risk of clinical and subclinical cerebrovascular disease [43].