Sickle cell disease: two thirds of stroke were cerebral infarctions.

Clinical bottom line (level 2c)

  1. Two thirds of strokes in patients with sickle cell disease were cerebral infarctions.
  2. A third of strokes were intracranial, subarachnoid or intracerebral haemorrhage.
  3. About 3% of strokes were due to embolism.
  4. Patients were at increased risk of a intracranial, subarachnoid or intracerebral haemorrhage if they had SS haemoglobin.
Powars et al: American Journal of Medicine 1978; 65: 461-471
Expires June 2003

The study

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

Setting: sickle cell centre, USA

35 patients (aged range 20 months to 36 years, ?% male) sickle cell disease and at least one stroke (cerebral infarction, subarachnoid haemorrhage, intracerebral haemorrhage, embolism)

Factors studied:
  • SS haemoglobin
  • SS haemoglobin
  • SS haemoglobin




    • 100% followed for ?
    Outcomes studied:
  • cerebral infarction
  • intracranial haemorrhage, subarachnoid and intracerebral
  • embolism

    • Thirty-three patients had sickle cell anaemia (SS) and two had SC.

    The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    cerebral infarction ? 23/35 65.7%
    (50.0% to 81.4%)
    intracranial haemorrhage, subarachnoid and intracerebral ? 11/35 31.4%
    (16.0% to 46.8%)
    embolism ? 1/35 2.86%
    (0.00% to 8.38%)

    prognostic factor for
    cerebral infarction     		time to outcome control rate (%) unadjusted OR
    (95% CI)    		 NNF+
    (95% CI)
    SS haemoglobin ? 23/35
    (65.7%)     		2.0
    (0.11 to 35)     		8
    (-6 to 1)

    prognostic factor for
    intracranial haemorrhage, subarachnoid and intracerebral     		time to outcome control rate (%) unadjusted OR
    (95% CI)
    SS haemoglobin ? 11/35
    (31.4%)     		inf
    (0.07 to inf)

    prognostic factor for
    embolism     		time to outcome control rate (%) unadjusted OR
    (95% CI)    		 NNF+
    (95% CI)
    SS haemoglobin ? 1/35
    (2.86%)     		0.0
    (0.0 to 1.9)     		-6
    (-5 to 9)

    • 55% of those who had subarachnoid or intracerebral haemorrhage died; 22% of those who had a cerebral infarction died.
    • Recurrence of cerebral infarction was 67%.

    Comments

    1. Uncertain of the length of follow-up which makes clinical use less clear.
    2. Odds ratios were not given, but calculated from data given.
    3. The study was too small to determine whether patients with SS are more likely to have a stroke than those with SC.

    Citation

    1. Powars D, Wilson B, Imbus C, et al: The natural history of stroke in sickle cell disease. American Journal of Medicine 1978; 65: 461-471
    Contributor: Clare Wotton and Musab Hayatli, June 2000
    Reviewer:

    Clinical Question.
    Patient sickle cell disease
    Intervention or Exposure prevalence
    Outcome stroke