Hemoglobin, Stroke, And You: Understanding The Link

Anemia is a decrease in red blood cells or hemoglobin in the blood. It is a common disease in about 10% of people aged 65 and older, and its prevalence increases with age. Anemia is a known risk factor for ischemic stroke and has been linked to a higher risk of death in older adults who have had a stroke. Research suggests that anemia may be associated with a higher risk of death after stroke, with both low and high levels of hemoglobin potentially increasing the risk. Anemia can cause a lack of oxygen delivery to the brain, leading to hypoxic conditions and death of brain tissue. While anemia is often overlooked as a risk factor for stroke, addressing it through timely transfusions may be an important step in preventing stroke and improving outcomes.

Anemia is a risk factor for ischemic stroke

Anemia alone is known to increase mortality risks in older adults, and when accompanied by cardiac diseases. Anemia at the time of hospitalization in patients with ischemic stroke increases the risk of death upon long-term follow-up. In a meta-analysis of observational studies lasting more than a year, mortality risk for both ischemic stroke and hemorrhagic stroke increased when accompanied by anemia.

Anemia is an independent risk factor for ischemic stroke and post-stroke mortality. Analysis of nationwide health insurance data revealed that anemia is one of the risk factors for the development of ischemic stroke.

Anemia increases the risk of post-stroke mortality

Anemia is a risk factor for ischemic stroke and post-stroke mortality. Anemia is a decrease in red blood cells or hemoglobin in the blood. It is a common disease in about 10% of people aged 65 and older, and its prevalence increases with age. Ischemic stroke is frequently accompanied by anemia. Previous studies have confirmed an average prevalence rate of 15-20%, and a maximum prevalence of 30%. Anemia alone is known to increase mortality risks in older adults, and when accompanied by cardiac diseases. Anemia at the time of hospitalization in patients with ischemic stroke increases the risk of death upon long-term follow-up. In a meta-analysis of observational studies lasting more than a year, mortality risk for both ischemic stroke and hemorrhagic stroke increased when accompanied by anemia.

A study conducted in South Korea analyzed health insurance claims data to confirm the development risk of ischemic stroke due to anemia. The study found that anemia is one of the risk factors for the development of ischemic stroke and an independent prognostic factor affecting post-stroke mortality. Another study found that anemia is associated with an increased risk of mortality in both ischemic stroke and hemorrhagic stroke. A retrospective study found that moderate to severe anemia is associated with poor functional outcomes in acute stroke patients treated with mechanical thrombectomy.

Anemia and low hemoglobin levels are common in older people

Anemia is a common condition in adults over 60 years old, with a prevalence of around 17%. The definition of anemia in older people is a subject of debate, with the World Health Organisation (WHO) defining it as a haemoglobin level of less than 130 g/L in men and less than 120 g/L in women. However, some studies suggest that these values should be adjusted to account for age, sex, and race. For example, a revised definition has been proposed, with a haemoglobin level of less than 12 g/dL in women and less than 13 g/dL in men over 65 years old.

Anemia is associated with increased morbidity and mortality in older adults. It is often asymptomatic and discovered incidentally through laboratory testing. However, it can also present with symptoms related to decreased oxygen-carrying capacity, such as weakness, fatigue, and shortness of breath. In older adults, the most common causes of anemia are nutritional deficiency, chronic kidney disease, and chronic inflammation. In about a third of cases, the cause is unknown.

Diagnostic cutoff values for anemia vary, but a serum ferritin level should be obtained for patients with normocytic or microcytic anemia. A low serum ferritin level in a patient with normocytic or microcytic anemia is associated with iron deficiency anemia. Older patients with suspected iron deficiency anemia should undergo endoscopy to evaluate for gastrointestinal malignancy. Patients with an elevated serum ferritin level or macrocytic anemia should be evaluated for underlying conditions, including vitamin B12 or folate deficiency, myelodysplastic syndrome, and malignancy.

Treatment is directed at the underlying cause of anemia. Symptomatic patients with serum haemoglobin levels of 8 g/dL or less may require blood transfusion. Patients with suspected iron deficiency anemia should be given a trial of oral iron replacement, with lower-dose formulations being as effective as standard preparations but with a lower risk of adverse effects.

Anemia is associated with a higher risk of death in older adults who have had a stroke

Anemia is a condition characterised by low levels of circulating red blood cells or hemoglobin, which causes a reduction in the amount of oxygen that is transported to the body's organs and tissues. It is a common condition, affecting around 10% of people aged 65 and above, and its prevalence increases with age.

Among patients who had ischemic stroke, the risk of death was increased twofold for those with anemia, compared with ischemic stroke patients who did not have anemia. Hemorrhagic stroke patients who had anemia were at 1.5 times greater risk of death.

A separate study of 90 adult patients who underwent mechanical thrombectomy found that moderate and severe anemia increased the risk of mortality.

Another study of 58,699 patients in South Korea found that anemia was associated with a higher risk of death in patients who had an ischemic stroke.

Overall, these studies suggest that anemia is associated with a higher risk of death in older adults who have had a stroke.

Anemia is a common condition in patients with acute stroke

In a study of 8,013 acute stroke patients, 24.5% had anemia on admission, and this was associated with increased odds of mortality at most time points up to 1 year following stroke. The risk of death was two times higher for those with ischemic stroke and anemia compared to those with ischemic stroke but without anemia. For hemorrhagic stroke patients with anemia, the risk of death was 1.5 times higher.

Anemia is associated with older age, increased stroke severity, higher pre-stroke disability, and a higher comorbidity burden. Anemia may worsen stroke outcomes by impairing oxygen delivery to the brain, compromising cerebrovascular autoregulation, and triggering thrombus formation.

In a retrospective study of 90 acute stroke patients treated with mechanical thrombectomy, moderate to severe anemia (hemoglobin levels below 10 g/dL) was found to be associated with poor functional outcomes. None of the patients with hemoglobin levels below 8 g/dL had a good functional outcome.

Overall, anemia is a common condition in acute stroke patients and is associated with increased mortality and poor functional outcomes.

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