Association Between Blood Hemoglobin Concentration and Mortality by Age and Sex : A Prospective Cohort Study.

Blood hemoglobin levels 1 to 3 g/dL above WHO thresholds are linked to the lowest long-term mortality risk in adults, with higher mortality observed below and above this range.

• Why it matters: Understanding the relationship between hemoglobin levels and mortality can improve clinical assessment and management of anemia and borderline cases, addressing gaps in current guidelines.
• What they did: A prospective cohort of over 500,000 UK adults was analyzed, measuring baseline hemoglobin and tracking mortality outcomes over a median of 13.6 years, stratified by age and sex.
• The result: Findings suggest mortality risk is minimized at hemoglobin concentrations slightly above WHO thresholds, highlighting the need to reconsider current cutoff points for better risk stratification.