Deep terminal negativity of the P‐wave in V1 and stroke risk: The National Health and Nutrition Examination survey III

BACKGROUND: Deep terminal negativity of the P-wave in V1 (DTNPV1) was considered if the absolute value of the depth of the negative phase was >100 μV in the presence of a biphasic P-wave in V1. In this study, we aimed to determine the association between DTNPV1, a simpler P-wave index, and the risk of stroke. METHODS: We compared P-wave indices between participants with and without a self-reported history of stroke in the United States Third National Health and Nutrition Examination Survey (NHANES III). The association between DTNPV1 and stroke was quantified with logistic regression models. RESULTS: In total, 7732 participants were included (307 with a history of stroke). Patients with stroke had deeper terminal negativity of the P-wave in V1 (52.3 ± 33.9 μV vs. 41.4 ± 27.0 μV, p < .001). After adjustment, DTNPV1 was associated with an increased risk of stroke (OR: 1.63, 95% CI: 1.03-2.60, p = .038). This association appeared to be stronger in people aged <75 years (interaction p = .023), and in those without heart failure (interaction p = .018) or ischemic heart disease (interaction p = .014). In contrast to the participants with 0 or ≥2 risk factors, in those with 1 risk factor, stroke prevalence was significantly different among the three categories of terminal negativity of the P-wave (0 μV, >0 μV but ≤100 μV and > 100 μV) in V1 (2.8%, 3.3%, and 10.3%, respectively, p = .005). CONCLUSION: In NHANES III, DTNPV1 was associated with a higher prevalence of stroke, suggesting that DTNPV1 might be a convenient marker to distinguish the risk of stroke.