Incidence trends of ischemic stroke and transient ischemic attacks in a well-defined French population from 1985 through 1994

Background and Purpose - The changing incidence of ischemic stroke is of ma jor concern in view of its public health impact, to define the population c oncerned, to identify risk factors, and to set up health-care systems. The aim of this study was to evaluate the time trends associated with the incid ence of all the subtypes of ischemic stroke and transient ischemic attacks in a well-defined population for 10 years. Methods - Since 1985, a population registry has recorded each patient livin g in Dijon (France) who suffered from a cerebrovascular disease (CVD) regar dless of the type of management. This study involved all patients suffering from their first ischemic stroke and their first transient ischemic attack s (TIAs) during 1 calendar year between January 1, 1985 and December 31, 19 94. The incidence changes according to age, sex, and type of cerebral ische mic event (cortico-subcortical infarct, lacunar infarct, and TIA) were stud ied on the basis of their annual variations. Results-During the 10-year study period, 834 cortico-subcortical infarcts ( 52.1%), 296 lacunar infarcts (18.5%), 369 TIAs (23.1%), and 101 undetermine d ischemic strokes (6.3%) were collected. The incidence of all ischemic eve nts was relatively stable in both sexes over the 10-year period. However, t he incidence rates differed according to age and type of ischemia. An incre ased incidence of cerebral cortico-subcortical infarct was observed in pati ents older than 75 years of age (+ 5.45% annual change [AC] in men, P < 0.0 5; + 5.09% AC in women, NS). In parallel, a higher proportion of emboligeni c cardiac arrhythmias was observed in these patients (P < 0.001). The incid ence of lacunar infarcts tended to decrease, regardless of age but mainly i n men under younger than 75 years of age (-12.74% AC in men, NS; + 0.31% AC in women, NS). The incidence of TIAs was relatively stable in both sexes. Because our population consisted of a large number of elderly subjects, the increase in cardioembolic causes could partially explain the increased inc idence of cerebral cortico-subcortical infarcts in patients older than 75 y ears of age. Conclusions - These preliminary data emphasize the importance of stroke sur veillance in considering the variations of the different mechanisms of isch emic cerebrovascular disease. Although the incidence of TIA is stable and t he incidence of lacunes tends to decrease in men, mainly before 75 years of age, we emphasize the rise of the crude incidence of cortico-subcortical i nfarcts in men older than 75 years of age, induced by an increase in cardio embolic causes.