Gender differences in the association between discharge hemoglobin and 12‐month mortality after acute myocardial infarction. Issue 12 (16th December 2017) - Thompson, Lauren E.
Abstract : Background: Anemia at discharge in patients with acute myocardial infarction is associated with poor prognosis; whether this differs in women and men or if there is a threshold value at which these relationships change is unknown. Hypothesis: Women have a lower discharge hemoglobin (Hb) at which outcomes worsen. Methods: We identified patients with acute myocardial infarction in the TRIUMPH registry between 2005 and 2008. In multivariable models, we evaluated the relationship between discharge Hb and 12‐month mortality and tested whether this relationship varied by gender. We assessed whether the relationship with discharge Hb values was nonlinear using a restricted cubic spline term. Results: Of 4243 patients with AMI, 32.9% were female. Mean admission Hb was 12.9 ± 1.9 g/dL in women and 14.5 ± 2.0 g/dL in men, with mean discharge Hb 11.4 ± 1.8 g/dL and 12.9 ± 1.9 g/dL, respectively. Lower discharge Hb was independently associated with increased mortality ( P < 0.05). In multivariable models, discharge Hb decline was similarly associated with increased 12‐month mortality in women and men (per 1‐g/dL decrease Hb; women HR: 1.24, 95% CI: 1.09‐1.42, P < 0.01; and men HR: 1.25, 95% CI: 1.13‐1.37, P < 0.01; P for gender interaction = 0.99). The relationship between discharge Hb and 12‐month mortality was linear ( P for nonlinear spline term = 0.12). Conclusions: Lower discharge Hb levels were similarly associated with increased 12‐month mortality in women and men. These relationships are linear without a clear threshold, suggesting any decline in discharge Hb is associated with poor outcomes.