Table 2

Key global differences and gaps regarding epidemiology, risk factors and aetiology of stroke in young adults

Important findingsMissing evidence
Global
  • Incidence of young stroke is rising

  • Prevalence of the modifiable vascular risk factors among young stroke patients is rising

  • PAR studies specific in young stroke patients

North-America
  • Highest prevalence (61.1%) of obesity (not young stroke specific)78 79

  • Higher incidence of stroke among young blacks and Hispanics (11/100 000 py) compared with whites (7/100 000 py)39 41

  • Higher young stroke mortality in blacks than in whites39 41

  • Uncertain incidence of moyamoya disease

South and Central America
  • Low prevalence of diabetes type 1 (not young stroke specific)67

  • Infectious causes of stroke including neurocysticercosis prevalent33

  • Lowest prevalence of hypertension globally together with North-America (35%)61

  • Missing information about risk factors (including PAR studies)

Europe
  • Increasing incidence over the last decade in many countries6

  • Extracranial artery dissections more common than intracranial dissections compared with Asia37 38

  • Highest prevalence of dyslipidaemia (54%)70

  • Prevalence of moyamoya disease uncertain

  • Few cases of patients with infectious causes

Africa
  • Higher percentage of infections, rheumatic heart disease and tuberculosis causing stroke

  • Highest prevalence of hypertension (46%)61

  • Highest prevalence (75%) of sickle cell disease23

  • Young adults with ischaemic stroke often have HIV in sub-Saharan Africa27

  • Lowest prevalence of dyslipidaemia globally with 22.6%70

  • Unknown incidence in >90% of countries.

  • No information about specific causes like dissection

Asia
  • Highest incidence of moyamoya disease (16.1/100 000 py Korea, 10.5/100 000 py Japan)16 17

  • Intracranial artery dissections more common than extracranial dissections37 38

  • Higher stroke severity (NIHSS 8) in Asians compared with blacks and whites (NIHSS 7 and 3)43

  • PAR of hypertension for stroke in general globally highest with 54.8%8

  • Unknown incidence of stroke in young adults for many Asian countries

Australia
  • Relatively high incidence of stroke in young adults with 20-30/100 000 py compared with other developed countries7

  • Young Aboriginal people have higher incidence of ischaemic stroke compared with non-Aboriginals44

  • Few specific continent-specific causes

  • PAR, population attributable risks; py, person-years.