The incidence of ischemic stroke in Norway has declined, mainly due to reduced prevalence of important risk factors. But in young women, the incidence has increased, according to the PhD thesis of Anne Merete Vangen-Lønne.
- The incidence of ischemic stroke has increased in young women the last decades, contrasting the results in older age groups.
- Lower blood pressure in the general population is the main cause of the reduced stroke incidence.
A feasible hypothetical intervention on several risk factors could reduce the 18-year stroke risk by 19%.
Thesis: Ischemic stroke in a general population: Time trends in incidence, case fatality and the impact of risk factor
Candidate: Anne Merete Vangen-Lønne
Time: October 13, 2017 at 12:15
Place: UiT Arctic University of Norway, The TANN Building: Auditorium
Link to university website (in Norwegian)
In her research, Vangen-Lønne has included more than 40 000 participants from six surveys of the Tromsø study, and followed them through 2012.
(1) The overall incidence of ischemic stroke declined with 27 % between 1995 and 2012. However, in women aged 30–49 years the incidence increased, and there was a similar trend among men in the same age group. Furthermore, 30-day case fatality decreased among men, but not women.
(2) Combined changes in traditional cardiovascular risk factors accounted for 57 % of the decreased stroke incidence between 1995 and 2012. Reduced blood pressure accounted for 26 % and reduced smoking for 17 %. Changes in cholesterol and physical activity have also played a role. However, an increasing prevalence of diabetes contributed negatively to the decline.
(3) A hypothetical, but feasible joint intervention on systolic blood pressure, total cholesterol, weight, physical activity, smoking and alcohol intake could have reduced the estimated 18-year stroke risk between 1995 and 2012 by 19% A more intensive intervention could have reduced the risk by more than 50 %.
(1) Vangen-Lønne, A. M., Wilsgaard, T., Johnsen, S. H., Carlsson, M., & Mathiesen, E. B. (2015). Time Trends in Incidence and Case Fatality of Ischemic Stroke. Stroke, 46(5), 1173-1179.
(2) Vangen-Lønne, A. M., Wilsgaard, T., Johnsen, S. H., Løchen, M. L., Njølstad, I., & Mathiesen, E. B. (2017). Declining Incidence of Ischemic Stroke. Stroke, 48(3), 544-550.
(3) To be published.