Nonfocal transient neurological attacks increase risk of future stroke and dementia

Clinical Question

Are patients with nonfocal transient neurological attacks at an increased risk of cardiovascular events?

Bottom Line

Adults experiencing nonfocal transient neurological attacks (TNAs) -- suddenly occurring decreased consciousness, confusion, unsteadiness, visual symptoms, paresthesias, bilateral weakness, and unwell feelings all resolving within 24 hours -- are at a significant increased risk of subsequent stroke and dementia. Clinicians caring for these patients may want to reinforce cardiovascular disease risk factor reduction efforts. (LOE = 1b)

Reference

Bos MJ, van Rijn MJ, Witteman JC, Hofman A, Koudstaal PJ, Breteler MM. Incidence and prognosis of transient neurological attacks. JAMA 2007;298(24):2877-2885.  [PMID:18159057]

Study Design

Cohort (prospective)

Funding

Government

Setting

Population-based

Synopsis

Uncertainty exists about the prognosis of patients experiencing nonfocal TNAs, defined as diffuse, nonlocalizing cerebral symptoms. These investigators analyzed data from the existing Rotterdam Study, a prospective, population-based cohort study of all residents, aged 55 years and older, from a specific district in the Netherlands. Eligible participants free from baseline cardiovascular disease (n = 6062) were continuously monitored for strokes, transient ischemic attacks, ischemic heart disease, dementia, and death for up to 15 years through a systemwide computerized database and regular surveys. Complete follow-up occurred for 96% of participants. TNAs were classified as focal, nonfocal, or mixed (both focal and nonfocal). Nonfocal symptoms included decreased consciousness, confusion, unsteadiness, visual symptoms, paresthesias, bilateral weakness, and unwell feelings, all occurring suddenly and completely resolving within 24 hours. Data were collected and verified by 2 independent investigators; differences were resolved by consensus. A third medical expert reviewed all final events. The cohort included 62% women and the median age at baseline was 68 years. A total of 548 participants experienced a TNA (282 focal, 228 nonfocal, and 38 mixed). As expected, compared with individuals without a history of TNA, those experiencing focal TNAs were at the highest risk of subsequent cardiovascular events and dementia, followed by those with mixed TNAs. Patients experiencing nonfocal TNAs were, however, also at a significantly increased risk of subsequent stroke compared with individuals not experiencing any events (11.8% vs 9.8%, respectively) and dementia (13.2% vs 10.0%, respectively), especially vascular dementia.