04.01.14
Nutraceutical: Iron
Indication: Stroke Risk
Source: PLOS ONE February 19, 2014
Research: Pulmonary first pass filtration of particles marginally exceeding ~7 µm (the size of a red blood cell) is used routinely in diagnostics, and allows cellular aggregates forming or entering the circulation in the preceding cardiac cycle to lodge safely in pulmonary capillaries/arterioles. Pulmonary arteriovenous malformations compromise capillary bed filtration, and are commonly associated with ischemic stroke. Cohorts with CT-scan evident malformations associated with the highest contrast echocardiographic shunt grades are known to be at higher stroke risk. The goal of researchers was to identify within this broad grouping, which patients were at higher risk of stroke.
This study included 497 consecutive patients with CT-proven pulmonary arteriovenous malformations due to hereditary hemorrhagic telangiectasia. Relationships with radiologically-confirmed clinical ischemic stroke were examined using logistic regression, receiver operating characteristic analyses and platelet studies.
Results: Sixty-one individuals (12.3%) had acute, non-iatrogenic ischemic clinical strokes at a median age of 52 (IQR 41–63) years. In crude and age-adjusted logistic regression, stroke risk was associated not with venous thromboemboli or conventional neurovascular risk factors, but with low serum iron (adjusted odds ratio 0.96 [95% confidence intervals 0.92, 1.00]), and more weakly with low oxygen saturations reflecting a larger right-to-left shunt (adjusted OR 0.96 [0.92, 1.01]). For the same pulmonary arteriovenous malformations, the stroke risk would approximately double with serum iron 6 µmol/L compared to mid-normal range (7–27 µmol/L). Platelet studies confirmed overlooked data that iron deficiency is associated with exuberant platelet aggregation to serotonin (5HT), correcting following iron treatment. By MANOVA, adjusting for participant and 5HT, iron or ferritin explained 14% of the variance in log-transformed aggregation-rate (p = 0.039/p = 0.021).
Researchers said data suggest patients with compromised pulmonary capillary filtration due to pulmonary arteriovenous malformations are at increased risk of ischemic stroke if they are iron deficient, and that mechanisms are likely to include enhanced aggregation of circulating platelets.
Indication: Stroke Risk
Source: PLOS ONE February 19, 2014
Research: Pulmonary first pass filtration of particles marginally exceeding ~7 µm (the size of a red blood cell) is used routinely in diagnostics, and allows cellular aggregates forming or entering the circulation in the preceding cardiac cycle to lodge safely in pulmonary capillaries/arterioles. Pulmonary arteriovenous malformations compromise capillary bed filtration, and are commonly associated with ischemic stroke. Cohorts with CT-scan evident malformations associated with the highest contrast echocardiographic shunt grades are known to be at higher stroke risk. The goal of researchers was to identify within this broad grouping, which patients were at higher risk of stroke.
This study included 497 consecutive patients with CT-proven pulmonary arteriovenous malformations due to hereditary hemorrhagic telangiectasia. Relationships with radiologically-confirmed clinical ischemic stroke were examined using logistic regression, receiver operating characteristic analyses and platelet studies.
Results: Sixty-one individuals (12.3%) had acute, non-iatrogenic ischemic clinical strokes at a median age of 52 (IQR 41–63) years. In crude and age-adjusted logistic regression, stroke risk was associated not with venous thromboemboli or conventional neurovascular risk factors, but with low serum iron (adjusted odds ratio 0.96 [95% confidence intervals 0.92, 1.00]), and more weakly with low oxygen saturations reflecting a larger right-to-left shunt (adjusted OR 0.96 [0.92, 1.01]). For the same pulmonary arteriovenous malformations, the stroke risk would approximately double with serum iron 6 µmol/L compared to mid-normal range (7–27 µmol/L). Platelet studies confirmed overlooked data that iron deficiency is associated with exuberant platelet aggregation to serotonin (5HT), correcting following iron treatment. By MANOVA, adjusting for participant and 5HT, iron or ferritin explained 14% of the variance in log-transformed aggregation-rate (p = 0.039/p = 0.021).
Researchers said data suggest patients with compromised pulmonary capillary filtration due to pulmonary arteriovenous malformations are at increased risk of ischemic stroke if they are iron deficient, and that mechanisms are likely to include enhanced aggregation of circulating platelets.