Bottom line: there was a significant decrease in ischemic stroke mortality among both men and women, but only a trend in decrease for hemorrhagic stroke. The authors attribute this distinction to the smaller sample size of hemorrhagic strokes. I would also point out that over this time period, there has arguably been more widespread use of acute treatments for ischemic stroke like IV-tPA and thrombectomy. The acute treatment of hemorrhagic stroke has enjoyed fewer innovations in the last decade.

Other trends found in this study include a significant drop in the mean age of stroke from 64 in 1980 to 62 in 2000 (p=0.0002). However the proportion of non-Caucasian patients in the metropolitan area did concurrently decrease over time. Thus whether this is a combination of racial disparities or a “stroke in the young” phenomenon is unclear. Length of hospital stay also dropped significantly from a median of 12 to 8 days over the same time period.
Limitations of this study include it being based solely in the Minneapolis-St. Paul metropolitan area. The authors point out that the US does not have nationwide long-term surveillance system for stroke patients. The cause of death being stroke related or not depended on ICD-9 diagnosis codes, which are subject to reporting bias. Neuroimaging techniques have also improved in quality and availability. This may have increased sensitivity in picking up minor strokes and diluted the severity of the stroke pool in later decades. Life expectancy in the general population had also improved over time and was specifically confirmed in this population.

The explanations for these trends are debatable, but regardless the numbers are encouraging and show that our efforts in the field of vascular neurology have positively impacted patient outcomes. Further study on a national and international level is warranted.

– Ali Saad, MD