Table 5. Characteristics of Studies Examining the Relationship Between Anemia and Hemoglobin Levels and Stroke Outcomes
AuthorYears SampledStudy DesignnExposureOutcomesMain Result
Bhatia et al62000–2001Prospective116Admission HbMortality at 30 daysHb not associated with outcome
Bussiere et al232003–2008Prospective2406Admission Hb divided into quintiles—cutoffs: 100, 120, 140, 160 g/LMortality at 1 year, mRS at dischargeHb predicted mortality at 1 year (aOR 1.39, 95% CI 1.01–1.91) in Hb <100 vs 141–160 g/L
Chang et al242008–2010Prospective106Admission Hb, nadir Hb, and transfusionIn‐hospital mortality, length of stay, and disability at dischargeAdmission anemia did not predict outcomes
Czlonkowska et al71991–1992Prospective345Admission HbMortality at 30 daysHb not associated with outcome
Diedler et al252004–2006Prospective196Admission, mean and nadir HbmRS at discharge and 6 monthsAdmission Hb did not predict outcomes
Del Fabbro et al162001–2003Retrospective890Anemia at admissionIn‐hospital mortality, survival at 1 yearHigher Hb predicted decreased mortality at 1 year: HR 0.98 (95% CI 0.97–1.00)
Gray et al261985–1986122Admission HbMortality at 4 and 12 weeksHb not associated with outcome
Hao et al22002–2008Prospective1176Anemia at admissionIn‐patient mortality, mortality, and disability (mRS >2) at 12 monthsAnemia associated with inpatient mortality (aOR 1.66, 95% CI 1.08–2.56) and mortality at 12 months (aOR 1.56, 95% CI 1.05–2.31)
Huang et al172001–2003Prospective774Anemia at admissionInpatient mortality, mRS at discharge, stroke recurrence at 3 yearsAnemia was associated with increased mortality at 3 years (aOR 2.22, 95% CI 1.13–4.39)
Kellert et al81998–2009Prospective217Admission, mean and nadir HbMortality and mRS at 3 monthsHb decrease was associated with increased mortality at 3 months (OR 1.34: 1.01–1.76) but admission Hb was not (OR not given)
Kumar et al181999–2005Prospective685Anemia at admissionMortality at 30 days, ICH volumeAnemia is not a predictor of mortality on multivariable analysis (OR 1.5, 95% CI 0.9–2.4)
Kuramatsu et al192006–2010Prospective435Anemia at admissionmRS at 90 days and 1 yearAnemia was associated with poor long‐term outcome (mRS 4–6 at 1 year; OR 7.5)
Milionis et al202003–2011Retrospective2439Anemia at admissionMortality and disability at 12 monthsAnemia associated with mortality at 12 months (OR 2.70, 95% CI 2.12–3.43)
Nybo et al212003–2004250Anemia at admissionMortality at 6 monthsAnemia associated with greater risk of death at 6 months (OR 4.7, 95% CI 1.1–8.2)
Park et al92004–2009Prospective2681Admission, nadir, time‐averaged, and discharge HbMortality and mRS at 3 monthsAdmission Hb predicted mortality 3 months (aOR: Q1 vs Q3 was 3.74 [95% CI 2.03–6.89] and Q5 vs Q3 was 1.99 [95% CI 1.02–3.91])
Sharma et al272003–2011Post hoc analysis of RCT3020Admission Hb and Hb <13 g/dLAll‐cause mortalityHb <13 g/dL was a significant predictor of mortality (HR 1.60, 95% CI 1.22–2.10)
Sico et al11998–2003Retrospective1306Anemia at admissionInpatient mortality or discharge to hospice (combined end point)Anemia was associated with outcome in patients with less severe stroke on subgroup analysis (aOR 4.17, 95% CI 1.47–11.90)
Tanne et al102001–2002Prospective859Anemia at admissionMortality at 1 month and 1 year, functional outcome using Barthel IndexaOR for mortality at 1 month was 1.90 (95% CI 1.05–3.43) and at 1 year was 1.72 (95% CI 1.00–2.93)
Wade et al281977–1982Post hoc analysis of RCT1377Hb >15 vs ≥15 g/dL on study entryFatal and nonfatal strokesNo significant difference in Hb levels among those who died compared with survivors
Zeng et al222007–2008Prospective2513Anemia on admissionMortality and dependency (mRS >2) at 1, 3, 6, and 12 monthsaOR for mortality in anemic versus nonanemic patients: 6 months 1.34 (95% CI 1.01–1.78), 1 year 1.33 (95% CI 1.00–1.75)
  • aOR indicates adjusted odds ratio; Hb, hemoglobin; HR, hazard ratio; ICH, intracerebral hemorrhage; mRS, modified Rankin Scale score; OR, odds ratio; Q, quintile; RCT, randomized controlled trial.