Association of Younger vs Older Ages With Changes in Incidence of Stroke and Other Vascular Events, 2002-2018

Abstract

IMPORTANCE Some studies have reported increasing stroke incidence at younger ages (<55 years) but have often relied only on administrative data, and more population-based studies of adjudicated stroke are required. An understanding of the drivers of any increase in incidence of young stroke also requires comparisons with stroke trends at older ages and with trends in incidence of other vascular events at younger ages.OBJECTIVE To determine temporal changes in incidence of stroke and other major vascular events at younger vs older ages. DESIGN, SETTING, AND PARTICIPANTS Prospective population-based incidence study conducted from April 2002 to March 2018 with a mean catchment population of 94 567 in Oxfordshire, England. EXPOSURES Calendar time, premorbid vascular risk factors, and occupation.MAIN OUTCOMES AND MEASURES Changes in incidence of stroke, transient ischemic attack (TIA), and other major vascular events (myocardial infarction, sudden cardiac death, and peripheral vascular events) stratified by age, sex, diagnostic workup, etiology, and severity.RESULTS A total of 2429 incident strokes were ascertained (mean age, 73.6 [SD, 14.4] years; 51.3% female). From 2002-2010 to 2010-2018, stroke incidence increased significantly among participants younger than 55 years (incidence rate ratio [IRR], 1.67; 95% CI, 1.31-2.14) but fell significantly among participants aged 55 years or older (IRR, 0.85; 95% CI, 0.78-0.92; P < .001 for difference). The significant increase in incidence at younger than 55 years was independent of sex, stroke severity, pathological subtype, and changes in investigation and was also seen for TIA (IRR, 1.87; 95% CI, 1.36-2.57) but not for myocardial infarction and other major vascular events (IRR, 0.73; 95% CI, 0.58-0.93). Although TIA and stroke at younger than 55 years were significantly associated with diabetes (risk ratio [RR], 3.47; 95% CI, 2.54-4.74), hypertension (RR, 2.52; 95% CI, 2.04-3.12), current smoking (RR, 2.38; 95% CI, 1.92-2.94), and obesity (RR, 1.36; 95% CI, 1.07-1.72), the significant increase in incidence from 2002-2010 to 2010-2018 was still seen in individuals without these risk factors. The increase was greatest in professional/managerial occupations (IRR, 2.52; 95% CI, 1.75-3.62) and least in partially skilled/unskilled occupations (IRR, 1.17; 95% CI, 0.79-1.74). The proportion of TIAs and strokes among those younger than 55 years without known vascular risk factors increased significantly over time (45 [30.4%] vs 115 [42.4%]; absolute difference, 12.0%; 95% CI, 2.6-21.5), especially in patients with cryptogenic events (10 [18.5%] vs 63 [49.

Diverging Temporal Trends in Stroke Incidence in Younger vs Older People

“…We were also reassured by the same directional change of incidence of TIA and stroke at younger ages in studies that reported both, and by the observation in our own study, that the incidence of disabling stroke at younger ages is increasing. 18 In relation to other potential biases, the relative increase in magnetic resonance brain imaging use over time in TIA/ stroke referrals has been similar at younger vs older ages in our own study and where it has been reported elsewhere. 4,18,49 Moreover, the similar increase in incidence of TIA and stroke at younger ages does not suggest diagnostic drift from TIA to stroke owing to increased use of magnetic resonance imaging.…”

“…18 However, although we showed that traditional vascular risk factors were highly prevalent and poorly controlled among young patients with stroke compared with the age-matched underlying population in the present population, 18 they did not appear to explain the increase of stroke incidence, particularly as incidence of myocardial infarction at younger ages is continuing to fall. 18 The impact of other emerging vascular risk factors, such as air pollution, appear to be age-specific, 90 and long working hours are more strongly associated with risk of stroke than myocardial infarction. 91 We showed that the age-specific divergence in stroke incidence was consistent for men and women, suggesting that sex-specific factors, such as pregnancy and oral contraceptive use, are unlikely to be major drivers, although we could not rule out an association of possible increases in exposure to environmental estrogen over time.…”

“…In relation to patient behavior, we did not find any temporal change in initial perception or behavior after stroke symptom onset in younger patients in Oxfordshire, UK. 18…”

“…This systematic review followed a prespecified protocol and is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. 17 PubMed and EMBASE were searched from inception to February 2022 and an additional populationbased study by Li et al 18 We searched for studies reporting stroke incidence in high-income countries at younger ages (usually <45, <55, or <60 years) during at least time 2 periods (full search strategy available in eTable 1 in the Supplement). We also scrutinized the reference lists of all relevant reviews and those of the eligible publications.…”

Exploring the risk factors for ischemic cerebrovascular disease in systemic lupus erythematosus: A single-center case-control study

“…This might be partially attributed to the relatively small sample size of the study. However, the significant increase in incidence of stroke and TIA was still seen in individuals younger than 55 years without these risk factors, as Li et al reported, which supported our findings ( 29 , 30 ). Moreover, in our study, we found that the prevalence of aPLs in lupus patients with ICVD was 25%–34%, and the incidence of aPLs positivity, especially aCL and LA positivity, was significantly higher versus patients in the non-ICVD group.…”