Both Ends of Values in the Hemoglobin Spectrum Are Associated with Adverse Stroke Outcomes

Abstract

<b><i>Background and Purpose:</i></b> Existing studies on the association between hemoglobin values and stroke outcomes mostly focus on the lower side and mortality, often the only and primary endpoint. The current study was conducted to assess the association between hemoglobin concentration and a variety of poor stroke outcomes in patients with acute ischemic stroke. <b><i>Methods:</i></b> We studied 8,321 patients enrolled in the China National Stroke Registry (CNSR) between 2007 and 2008. Patients were divided into 7 groups, and a logistic regression model was used to evaluate the association. Endpoints of interest included 1-year all-cause mortality, stroke recurrence, combined endpoint, and stroke disability. Stroke disability was defined as a modified Rankin Scale of 2–6. <b><i>Results:</i></b> Patients with low and high hemoglobin values (≤11.6 g/dL and >16.1 g/dL) had higher proportion of poststroke adverse events than those in other groups. As compared with the fourth group of hemoglobin values of 13.5–14.2 g/dL, the adjusted odds ratios (ORs) with 95% confidence interval (CI) of low hemoglobin values (≤11.6 g/dL) were 2.25 (1.72–2.93) for all-cause mortality, 1.30 (1.04–1.61) for stroke recurrence, 1.63 (1.33–2.01) for combined endpoint, and 1.37 (1.12–1.67) for stroke disability, respectively. And, the ORs of high hemoglobin values (>16.1 g/dL) for adverse stroke outcomes were 1.72 (1.25–2.37), 1.43 (1.13–1.82), 1.43 (1.13–1.81), and 1.31 (1.06–1.63), respectively. Stratified analysis showed significant interactions between sex and categories of hemoglobin values for all-cause mortality (<i>p</i> = 0.05), stroke recurrence (<i>p</i> = 0.03), and combined endpoint (<i>p</i> = 0.01) but not for stroke disability (<i>p</i> = 0.24). <b><i>Conclusions:</i></b> Our study found both low and high hemoglobin values were associated with adverse stroke outcomes including all-cause mortality, stroke recurrence, combined endpoint, and stroke disability, which showed a U-shaped association. And, significant interactions between sex and hemoglobin concentration on all-cause mortality and stroke recurrence were also identified.

The relationship between hemoglobin and triglycerides in moyamoya disease: A cross-sectional study

“…The Hb level is an easily accessible and sensitive clinical indicator that reflects the physiological status of the body ( 7 , 13 ). A recent study ( 12 ) showed a U-shaped association between hemoglobin concentration and stroke sequelae and recurrence, with either too high or too low hemoglobin concentrations being associated with stroke disability, death and recurrence. Meanwhile, a multicentre study ( 14 ) noted that elevated hemoglobin concentrations within 3 months of onset were associated with poor prognosis in men but not significantly in women with cerebral hemorrhage.…”

“…There is a positive association between the Hb concentration and inflammation in previously and currently infected populations ( 7 , 9 , 10 ). Furthermore, the Hb concentration is a well-known independent risk factor for stroke and a poor prognosis ( 11 , 12 ). In general, both Hb and TGs play crucial roles in the pathology and physiology of cerebrovascular disease, although the relationship between the two has not been elucidated.…”

Association between baseline hemoglobin level and early neurological deterioration after intravenous thrombolysis in patients with acute ischemic stroke

“…本文资料显示，在发病4.5 h内接受静脉溶栓的AIS患者中，贫血的发生率为17.9%，与既往研究报道基本一致 ［ 16 ］ 。此外，与非END患者比较，END患者年龄更大，基线血红蛋白水平更低，贫血比率更高，高血压、糖尿病、心房颤动、脑卒中史和冠心病的发生率也更高，与之前的研究结果一致 ［ 17 - 18 ］ ，提示基线血红蛋白水平可能与AIS患者静脉溶栓后END的发生具有一定相关性。有研究发现，AIS患者入院时血红蛋白水平与脑卒中严重程度呈U型关系，贫血和血红蛋白增多均与神经功能结局不良相关 ［ 19 - 20 ］ 。本研究进一步分析显示，基线血红蛋白水平与END之间存在U型相关性，即血红蛋白水平升高或降低均会增加AIS患者静脉溶栓后END发生风险，其中重度贫血患者静脉溶栓后END发生风险显著增加。…”

“…值得注意的是，有研究显示高血红蛋白水平仅与男性患者卒中后的不良神经功能结局相关 ［ 19 ］ 。本文资料也显示，血红蛋白水平与END之间的U型相关性仅在男性患者中观察到，在女性患者中未观察到。分析原因可能是因为贫血在女性中更为常见，而高血红蛋白水平在男性中更为常见 ［ 12 ］ ，但血红蛋白水平与END之间的关系存在性别差异的具体机制仍有待进一步研究。…”