Incidence and prognosis of transient neurological attacks
Context: Transient neurological attacks (TNAs) are attacks with temporary (<24 hours) neurological symptoms. These symptoms can be focal, nonfocal, or a mixture of both. The prognostic significance of TNAs with focal symptoms (better known as transient ischemic attacks [TIAs]) is well understood. Conversely, hardly anything is known about the prognostic significance of TNAs with nonfocal or mixed symptoms. Objective: To study the incidence and prognosis of focal TNAs (or TIAs), nonfocal TNAs, and mixed TNAs. Design, Setting, and Participants: The study population comprised 6062 community-dwelling Rotterdam Study participants who were aged 55 years or older and free from stroke, myocardial infarction, and dementia at baseline (1990-1993). They were followed up for events until January 1, 2005. We analyzed the associations between incident TNAs and subsequent adverse events with age- and sex-adjusted Cox regression models. Main Outcome Measures: Stroke, ischemic heart disease, or dementia. Results: During 60 535 person-years, 548 participants developed TNA (282 focal, 228 nonfocal, and 38 mixed). The incidence rate per 1000 person-years was 4.7 (95% confidence interval [CI], 4.1-5.2) for focal TNA, 3.8 (95% CI, 3.3-4.3) for nonfocal TNA, and 0.6 (95% CI, 0.4-0.9) for mixed TNA. Participants with focal TNA were at higher risk of subsequent stroke than participants without TNA (n=46 vs 540; hazard ratio [HR], 2.14; 95% confidence interval [CI]; 1.57-2.91) but had an equal risk of ischemic heart disease and dementia. Nonfocal TNA patients were at higher risk of stroke (27 vs 540; HR, 1.56; 95% CI, 1.08-2.28) and dementia (30 vs 552; HR, 1.59; 95% CI, 1.11-2.26) than participants without TNA. Mixed TNA patients were at higher risk of stroke (6 vs 540; HR, 2.48; 95% CI, 1.11-5.56), ischemic heart disease (8 vs 779; HR, 2.26; 95% CI, 1.07-4.78), vascular death (8 vs 594; HR, 2.54; 95%CI, 1.31-4.91), and dementia (7 vs 552; HR, 3.46; 95% CI, 1.72-6.98) than participants without TNA. Conclusion: Patients who experience nonfocal TNAs, and especially those with mixed TNAs, have a higher risk of major vascular diseases and dementia than persons without TNA.