Letter by Yang et al Regarding Article, "Hemoglobin Concentration and Risk of Incident Stroke in Community-Living Adults".

We read the recent article by Panwar et al1 with great interest. This large cohort prospective study indicated that lower and higher hemoglobin concentrations were associated with a higher risk of incident stroke in women. No such associations were found in men. However, results from the study should be interpreted with several considerations. First, this study only collected the enrollment measurement of hemoglobin, despite having a long follow-up period (7±2 years). However, longitudinal hemoglobin levels were not assessed. Furthermore, hemoglobin levels are most accurately measured within 24 hours of acute stroke onset. In a study by Furlan et al,2 an elevated level of hemoglobin …