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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Biomarkers, Cardiovascular Diseases, Female, Ferritins, Follow-Up Studies, Hemoglobins, Humans, Male, Middle Aged, Norway, Prevalence, Prognosis, Retinal Vein, Retrospective Studies, Sex Factors, Venules.
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Are serum ferritin and hemoglobin independently associated with wider retinal venular caliber : the Tromsø Study 2001-2008? Context: To investigate if markers of iron body stores and hemoglobin are associated with retinal vascular caliber. This was a population-based study including 2993 participants of the fifth and sixth surveys of the Tromsø Study in Norway, conducted in 2001-2002 and 2007-2008. The association between levels of s-ferritin, transferrin saturation, and hemoglobin in the fifth survey and retinal vascular caliber in the sixth survey was assessed by multivariable linear regression models. Men had higher levels of hemoglobin and s-ferritin than women. Hemoglobin was associated with wider retinal venules in both men and women (mean difference between highest compared to lowest sex-specific quartile: men 5.99 μm, P = 0.001; women 7.28 μm, P < 0.001). S-ferritin was associated with wider retinal venules in men but not women, independent of traditional risk factors (mean difference between highest compared to lowest sex-specific quartile: men 4.21 μm, P = 0.013; women -0.21 μm, P = 0.89). The association in men was attenuated, but still significant, with adjustment for hemoglobin. S-ferritin and level of hemoglobin were not associated with arteriolar caliber in either sex. Transferrin saturation was not associated with retinal vascular caliber.
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Level of hemoglobin was associated with wider retinal venules in both sexes while s-ferritin was associated with wider retinal venular caliber only in men. Men have higher levels of stored iron, and this may underlie the observed sex difference in the association between s-ferritin and retinal vascular caliber. Final Decision: yes