Time Trends in Incidence and Case Fatality of Ischemic Stroke

Abstract

Background and Purpose-Ischemic stroke incidence has declined in industrialized countries the last decades, with possible exception for the youngest age groups. We estimated age-and sex-specific trends in incidence and case fatality of firstever ischemic stroke between 1977 and 2010 in a Norwegian municipality. Methods-Age-adjusted time trends in incidence from 1977 to 2010 were estimated by fractional polynomial and Poisson regression, and case fatality by logistic regression in 36 575 participants of the population-based Tromsø Study. Results-There were 1214 first-ever ischemic strokes within a total follow-up time of 611 176 person-years. The overall age-and sex-adjusted incidence decreased by 24% in 1995 to 2010. In women aged 30 to 49 years, the incidence increased significantly from 1980 to 2010. In men aged 30 to 49 years, there was a nonsignificant, rising trend from 1977 to 2010. Men aged 50 to 64 years had similar incidence in 2010 compared with 1989. From the mid-1990s to 2010, the incidence declined significantly in women aged 50 to 74 years and in men aged 65 to 74 years, but remained stable in those aged ≥75 years. Case fatality decreased significantly in men aged 30 to 84 years from 1995 to 2010, whereas there was no significant change in women. Conclusions-Age-adjusted incidence of first-ever ischemic stroke increased in young women, declined in women aged 50 to 74 years and men aged 65 to 74 years and remained stable among the oldest. Case fatality declined in men aged 30 to 84 years, but not in women.

Temporal Trends of Stroke Epidemiology in Southern Sweden: A Population-Based Study on Stroke Incidence and Early Case-Fatality

“…The observed decline in stroke incidence in our study was confined to IS, whereas the incidence of hemorrhagic stroke remained unchanged. Similarly, a study from Tromsø, Norway, reported a 24% decrease in first-ever IS incidence between 1995 and 2010 [23]. The absolute number of incident first-ever stroke cases decreased by almost 10% in our study area between 2001–2002 and 2015–2016 despite an increase in population size with 18%, as well as a 1% increase in the proportion of individuals ≥75 years.…”

Global Burden of Thrombosis

“…Mortality after stroke in the ARIC communities declined over time by 10% to 20%, particularly among those aged <65 years. Similar trends have been observed in men (but not women) in the Framingham study 32 in Minneapolis-St. Paul 33 ; in Tromsø, Norway 34 ; and in Auckland, New Zealand, 35 but not observed in Oxfordshire, United Kingdom 36 or Perth, Australia. 37 Even greater decreases in mortality because of stroke were observed in Denmark (45% reduction from 1994-1998 to 2009-2011)…”

Longitudinal and Secular Trends in Blood Pressure Among Women and Men in Birth Cohorts Born Between 1905 and 1977

“…22 Ischemic stroke incidence declined during 1995 to 2010 and case-fatality declined in men but not in women. 23 Intracerebral hemorrhage incidence showed no time trends during 1995 to 2010. 24 CVD risk factor reduction, mainly through decrease in total cholesterol, blood pressure, and prevalence of smoking, explain more than half of the reduction in coronary heart disease mortality observed in Norway's neighboring countries, Finland 25 and Sweden, 26 from the 1980s and onwards.…”