Stroke: subtypes could help predict functional outcome, recurrent stroke and death

Clinical bottom line (level 1b)

  1. Patients with a cardioembolic stroke had the worst functional outcomes and patients with lacunar strokes the best.
  2. Patients with an atherosclerotic stroke were most likely to have a recurrent stroke within 30 days and patients with lacunar strokes were least likely to have one within 30 days.
  3. Recurrent stroke was common in all stroke subtypes at 5 years.
  4. Patients with a cardioembolic stroke were most likely to die at 30 days, and patients with a lacunar stroke were least likely to die at 30 days.
  5. Death was common in all stroke subtypes at 5 years - but atherosclerotic stroke reduced the risk of dying.
Petty et al: Stroke 2000; 31 : 1062-1068
Expires November 2003

The study

Inception cohort study with objective outcomes, adjusted for confounding factors, not validated in an independent set of patients.

Setting: city, USA

442 patients with a first ischaemic stroke

Excluded if
  • unusual cause of stroke: vasculitis, malignancy causing hypercoagulability, dissection
  • not resident in Rochester for a year before stroke


Factors studied:
  • age, sex, stroke risk factors, stroke subtype, severity



    Cox proportional hazards regression analysis was used to identify predictors of mortality and recurrent stroke for each stroke subtype.

    100% followed for
    Outcomes studied:
  • atherosclerosis: good functional outcome
  • cardioembolic: good functional outcome
  • lacunar: good functional outcome
  • unknown cause: good functional outcome
  • atherosclerosis: recurrent stroke
  • cardioembolic: recurrent stroke
  • lacunar: recurrent stroke
  • unknown: recurrent stroke
  • atherosclerosis: recurrent stroke
  • cardioembolic: recurrent stroke
  • lacunar: recurrent stroke
  • unknown cause: recurrent stroke
  • atherosclerotic: death
  • cardioembolic: death
  • lacunar: death
  • unknown cause: death
  • atherosclerotic: death
  • cardioembolic: death
  • lacunar: death
  • unknown cause: death
    • Strokes were classified into 4 subtypes
      • large-vessel cervical or intracranial atherosclerosis with stenosis (16%)
      • cardioembolic (29%)
      • lacunar (16%)
      • infarct of uncertain cause (36%)

    The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)    		 NNF
    (95% CI)
    atherosclerosis: good functional outcome 12 months 39/74 53%
    (41% to 64%)    		 2
    (2 to 2)
    cardioembolic: good functional outcome 12 months 35/132 27%
    (19% to 34%)    		 4
    (3 to 5)
    lacunar: good functional outcome 12 months 59/72 82%
    (73% to 91%)    		 1.2
    (1.1 to 1.4)
    unknown cause: good functional outcome 12 months 81/164 49%
    (42% to 57%)    		 2
    (2 to 2)
    atherosclerosis: recurrent stroke 30 days / 18.5%
    (9.7% to 27.5%)    		 5
    (4 to 11)
    cardioembolic: recurrent stroke 30 days / 5.3%
    (1.2% to 9.6%)    		 19
    (10 to 83)
    lacunar: recurrent stroke 30 days / 1.4%
    (0.0% to 4.1%)    		 71
    (24 to infinity)
    unknown: recurrent stroke 30 days / 3.3%
    (0.4% to 6.2%)    		 30
    (16 to 250)
    atherosclerosis: recurrent stroke 5 years / 40.2%
    (27.9% to 55.0%)    		 2
    (2 to 4)
    cardioembolic: recurrent stroke 5 years / 31.7%
    (18.2% to 47.3%)    		 3
    (2 to 5)
    lacunar: recurrent stroke 5 years / 24.8%
    (14.1% to 39.3%)    		 4
    (3 to 7)
    unknown cause: recurrent stroke 5 years / 33.2%
    (24.2% to 42.3%)    		 3
    (2 to 4)
    atherosclerotic: death 30 days / 8.1%
    (1.9% to 14.3%)    		 12
    (7 to 53)
    cardioembolic: death 30 days / 30.3%
    (22.5% to 38.1%)    		 3
    (3 to 4)
    lacunar: death 30 days / 1.4%
    (0.0% to 4.1%)    		 71
    (24 to infinity)
    unknown cause: death 30 days / 14.0%
    (8.7% to 19.3%)    		 7
    (5 to 11)
    atherosclerotic: death 5 years / 32.2%
    (21.1% to 43.8%)    		 3
    (2 to 4)
    cardioembolic: death 5 years / 80.4%
    (73.1% to 88.1%)    		 1
    (1 to 1)
    lacunar: death 5 years / 35.1%
    (23.6% to 47.6%)    		 3
    (2 to 4)
    unknown cause: death 5 years / 48.6%
    (40.5% to 56.8%)    		 1
    (1 to 1)

    • Recurrent stroke within 30 days was more likely with atherosclerotic stroke with stenosis (RR: 3.34; 95% CI: 1.20 to 9.27)
    • Recurrent stroke at 5 years was more likely with diabetes mellitus (RR 1.88; 95% CI: 1.25 to 2.85), but no stroke subtype.
    • Death at 30 days was more likely with
      • increasing age (RR 1.31; 95% CI: 1.03 to 1.68)
      • worsening functional outcome - Rankin score 4 or 5 (RR 11.6; 95% CI: 2.77 to 48.8)
      but no stroke subtype
    • Death at 5 years was more likely with
      • increasing age
      • congestive heart disease
      • ischaemic heart disease at 40 years of age
      • worsening disability - Rankin score 4 or 5
      and less likely with atherosclerotic stroke with stenosis.

    Citation

    1. Petty GW, Brown RD, Whisnant JP, et al: ischemic stroke subtypes: a population-based study of functional outcome, survival and recurrence. Stroke 2000; 31 : 1062-1068
    Search Terms: from ACP Journal Club
    Contributor: Chris Ball, November 2001
    Reviewer:

    Clinical Question.
    Patient first ischaemic stroke
    Intervention or Exposure stroke subtype
    Outcome functional outcome, death, recurrent stroke

The evidence

outcome time to outcome number of patients/total number %
(95% CI)		 NNF
(95% CI)
atherosclerosis: good functional outcome 12 months 39/74 53%
(41% to 64%)		 2
(2 to 2)
cardioembolic: good functional outcome 12 months 35/132 27%
(19% to 34%)		 4
(3 to 5)
lacunar: good functional outcome 12 months 59/72 82%
(73% to 91%)		 1.2
(1.1 to 1.4)
unknown cause: good functional outcome 12 months 81/164 49%
(42% to 57%)		 2
(2 to 2)
atherosclerosis: recurrent stroke 30 days / 18.5%
(9.7% to 27.5%)		 5
(4 to 11)
cardioembolic: recurrent stroke 30 days / 5.3%
(1.2% to 9.6%)		 19
(10 to 83)
lacunar: recurrent stroke 30 days / 1.4%
(0.0% to 4.1%)		 71
(24 to infinity)
unknown: recurrent stroke 30 days / 3.3%
(0.4% to 6.2%)		 30
(16 to 250)
atherosclerosis: recurrent stroke 5 years / 40.2%
(27.9% to 55.0%)		 2
(2 to 4)
cardioembolic: recurrent stroke 5 years / 31.7%
(18.2% to 47.3%)		 3
(2 to 5)
lacunar: recurrent stroke 5 years / 24.8%
(14.1% to 39.3%)		 4
(3 to 7)
unknown cause: recurrent stroke 5 years / 33.2%
(24.2% to 42.3%)		 3
(2 to 4)
atherosclerotic: death 30 days / 8.1%
(1.9% to 14.3%)		 12
(7 to 53)
cardioembolic: death 30 days / 30.3%
(22.5% to 38.1%)		 3
(3 to 4)
lacunar: death 30 days / 1.4%
(0.0% to 4.1%)		 71
(24 to infinity)
unknown cause: death 30 days / 14.0%
(8.7% to 19.3%)		 7
(5 to 11)
atherosclerotic: death 5 years / 32.2%
(21.1% to 43.8%)		 3
(2 to 4)
cardioembolic: death 5 years / 80.4%
(73.1% to 88.1%)		 1
(1 to 1)
lacunar: death 5 years / 35.1%
(23.6% to 47.6%)		 3
(2 to 4)
unknown cause: death 5 years / 48.6%
(40.5% to 56.8%)		 1
(1 to 1)

 

  • Recurrent stroke within 30 days was more likely with atherosclerotic stroke with stenosis (RR: 3.34; 95% CI: 1.20 to 9.27)
  • Recurrent stroke at 5 years was more likely with diabetes mellitus (RR 1.88; 95% CI: 1.25 to 2.85), but no stroke subtype.
  • Death at 30 days was more likely with
    • increasing age (RR 1.31; 95% CI: 1.03 to 1.68)
    • worsening functional outcome - Rankin score 4 or 5 (RR 11.6; 95% CI: 2.77 to 48.8)
    but no stroke subtype
  • Death at 5 years was more likely with
    • increasing age
    • congestive heart disease
    • ischaemic heart disease at 40 years of age
    • worsening disability - Rankin score 4 or 5
    and less likely with atherosclerotic stroke with stenosis.

Citation

 

  1. Petty GW, Brown RD, Whisnant JP, et al: ischemic stroke subtypes: a population-based study of functional outcome, survival and recurrence. Stroke 2000; 31 : 1062-1068
Search Terms: from ACP Journal Club
Contributor: Chris Ball, November 2001
Reviewer:

Clinical Question.
Patient first ischaemic stroke
Intervention or Exposure stroke subtype
Outcome functional outcome, death, recurrent stroke