Pathologic Study of Intracranial Large Artery Atherosclerosis in 7260 Autopsy Cases

Background: Atherosclerotic changes in the cerebral arteries may differ with era of birth. Herein, we analyzed the chronological changes of intracranial atherosclerosis in consecutive autopsy cases. Methods: A total of 7260 autopsy cases from 1972 to 2014 were analyzed. Severity of atherosclerosis was classified using a semi-quantitative scale of pathologic observation of each artery after formalin fixation: 0 = no stenosis; .5 = fatty streaks but no stenosis; 1 = <50% stenosis; 2 = 50%-90% stenosis; 3 = >= 90% stenosis. The bilateral vertebral, anterior, middle, and posterior cerebral arteries and the basilar artery were scored. The sum of each individual was defined and compared by age at death, sex, and era of birth. Results: The atherosclerosis score increased with age at death, as follows: age in the 50s, 0 [02]; 60s, 3 [.5-7]; 70s, 5 [2-9.5]; 80s, 6.5 [3.5-11.5]; 90s, 7.75 [4-12]; and 100s, 8 [5.5-13.5] (median value [interquartile range], P < .0001). The percentage of cases with a score of 2 or 3 in each artery also increased with age (P < .0001). Atherosclerosis score was higher in men than women in their 60s at death, and was higher in women than men in their 80s and 90s at death. In each age at death group (from 60s to 100s), the score declined with later year of birth (P < .05). Conclusions: Intracranial atherosclerosis advances with age and is more severe in subjects born earlier.