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Non Hispanic Black Americans

The annual incidence for first-ever stroke is higher for black individuals than white individuals for ischemic, intracerebral hemorrhage and subarachnoid hemorrhage.  Between 45 and 64 years of age, black men and women have a particularly high stroke/TIA risk (2-3 times higher than age-matched white subjects). It is estimated that about 40% of the excess stroke risk in non-Hispanic blacks can be attributed to the risk factors we have discussed. Of those, levels of systolic blood pressure account for about half of the increased risk among blacks compared to whites. The racial disparity in stroke incidence does not seem to be changing over time. Additionally, more blacks die soon after a stroke, and black stroke survivors have greater long-term activity limitations than do white stroke survivors after controlling for stroke severity and rehabilitation use.

The prevalence of hypertension in non-Hispanic black adults in the US is currently estimated to be about 45%. This is among the highest in the world. The prevalence of hypertension in non-Hispanic white adults is about 33%. Efforts to raise awareness of hypertension and its dangers in the black community have apparently been successful. But despite this success, the odds that black individuals will achieve their blood pressure targets are lower than for whites.

In a 2011-2014 survey, the prevalence of physician-diagnosed diabetes in non-Hispanic black adults age 20 and older was about 14% (in non-Hispanic whites the prevalence was about 8%).

Even when the statistics are adjusted for age, hypertension, and diabetes, the relative risk of stroke among blacks is reported to be higher than among whites.

Rates of stroke mortality are highest in a region of the southeastern US which is known as the ‘Stroke Belt.’ This area is variably defined, but usually includes the states of North Carolina, South Carolina, Georgia, Tennessee, Mississippi, Alabama, Louisiana, and Arkansas.  In this region average stroke mortality is about 30% higher than in the rest of the US. This geographic disparity has existed more or less unchanged for the past 70 years. Even more striking, within this ‘Stroke Belt’ the coastal regions of North Carolina, South Carolina, and Georgia have average stroke mortality that is about 40% higher than in the rest of the nation.

Blacks who live in this so-called ‘Stroke Belt’ have sharply increased stroke mortality rates; whites also have somewhat increased rates. The high rate of stroke among ‘Stroke Belt’ residents does not appear to be the result of poor hypertension treatment and control. A clear explanation has so far eluded public health experts.

In the US, most people with sickle cell disease are non-Hispanic blacks. Sickle cell disease is strongly associated with stroke, especially in children. In these individuals, the vascular endothelium may be damaged by repeated episodes of red cell sickling, making it prone to thrombus formation. Long-term exchange transfusion or bone marrow transplants can prevent the vascular pathology from progressing, and therefore decrease the risk of stroke. If a child with sickle cell disease has a stroke, he or she often recovers quite well, thanks perhaps to the increased plasticity of the young nervous system. However, without therapy, these children remain at high risk for additional strokes that may produce a lifetime of disability.