Background and objectives: Nonfocal transient neurologic attacks (TNA) have been suggested to increase the risk of stroke, yet the optimal clinical approach of these attacks remains uncertain. We determined whether people who have a nonfocal TNA are at an increased risk of subsequent cardiovascular disease (CVD), akin to the known increased risk of stroke following transient ischemic attack (TIA).
Methods: Within a population-based cohort study among Dutch participants aged 45 years or older, we selected participants who had first-ever TNA, defined as an attack of sudden neurologic symptoms resolving within 24 hours without clear evidence for an alternative diagnosis, during follow-up between 1990 and 2020. Nonfocal TNAs were attacks with nonfocal symptoms only, whereas attacks with focal symptoms were regarded as TIA. Each participant with TNA was matched to 2 participants who did not experience TNA, with similar age and sex at the date of TNA diagnosis. Participants were then followed up for any incident CVD, defined by any stroke or any coronary heart disease (CHD), and follow-up was complete for 98.6% of potential person-years. The association between TNA and risk of subsequent CVD was analyzed using Cox proportional hazard models adjusting for demographic and cardiovascular risk factors at baseline.
Results: During follow-up, 1,208 participants (mean [SD] age 76.9 [9.3] years, 65.4% female) experienced a first-ever TNA and were matched to 2,416 participants without TNA. After 27,833 person-years of follow-up, 230 (19.0%) participants suffered stroke and 94 (7.8%) suffered CHD. For those without TNA, these numbers were 250 (10.4%) and 176 (7.3%). Incident nonfocal TNA was not associated with the risk of any stroke (hazard ratio 1.25%, 95% CI [0.89-1.77]), only ischemic stroke (1.26 [0.76-2.08]), any CHD (0.80 [0.49-1.31]), and only acute myocardial infarction (0.89 [0.51-1.56]). By comparison, participants with TIA had an increased risk of all stroke (2.55 [2.04-3.19]) and ischemic stroke (2.51[1.88-3.35]).
Discussion: In this study, participants with nonfocal TNA did not have a subsequently elevated risk of CVD when compared with their matched counterparts, which contrasts with the elevated risk of stroke following a TIA. In the absence of other indications, initiating secondary prevention specifically after nonfocal TNA seems unwarranted.