Data were evaluated for patients with acute ST-elevation myocardial infarction (n = 94,182) enrolled in 6 large clinical trials evaluating the efficacy of various reperfusion strategies. It was found that compared with the tallest quartile, incidences of in-hospital reinfarction, stroke, major bleeding, cardiogenic shock, heart failure, and death in the shortest group were 1.4, 1.7, 1.7, 1.8, 1.9, and 2.4 times greater, respectively. Although a strong inverse association of height was observed with unadjusted 30-day mortality (p <0.001), it was attenuated after adjustment for confounders, including weight, and appeared to be nonlinear, such that for height </=165 cm, the odds ratio [OR] for a 10-cm increment in height was 1.115 (95% confidence interval [CI] 1.014 to 1.223) and for height >165 cm, the OR for a 10-cm increase in height was 0.962 (95% CI 0.896 to 1.033). These data indicate that height-related differences in 30-day mortality are explained in large part by height-related differences in patients' clinical characteristics.