Should octogenarians and people aged 90 years and over be treated separately in studies of stroke? An evaluation of national audit data.

Introduction: Population studies frequently use ≥80 years for defining 'very old' but as mean life expectancy frequently exceeds 80 years internationally, this may no longer be appropriate. Those ≥90 years now represent a significant proportion of stroke patients. We examined national data to examine the differences between those 80-89 years and those 90+ years.