Background: Few studies have tested differences in relationships between hemoglobin (Hb) and long-term risk of major cardiovascular diseases according to age and gender in healthy subjects as opposed to anemia.
Aims: Such relationships were examined and risk-tested in relation to Hb values in the Apolipoprotein MOrtality RISk (AMORIS) Study.
Methods: Using data from AMORIS and the Swedish hospital discharge and mortality registers, a prospective cohort study of 114,159 subjects with mean follow-up of 11.8 years, the association between Hb and risk of acute myocardial infarction (AMI), ischemic stroke (IS), and congestive heart failure (CHF) by Cox regression analysis according to age and gender was studied.
Results: Elevated Hb levels were associated to acute myocardial infarction (AMI) (HR 1.10 (1.06-1.13) per SD change), mostly confined to men and younger subjects but with greater sex similarity trends for CHF. Slightly increased risks were seen for the lowest Hb levels in the elderly and in females. IS risk was positively and more linearly associated to Hb.
Interpretation: In AMORIS the highest AMI and CHF risks were found in the upper region of the distribution, but different shapes of relationships according to age and gender were found. IS associated positively with Hb. Key words: