Survival after traumatic injury may be influenced by sex hormones (estrogen and testosterone) and their effects on inflammatory processes.

Previously, Addison May and colleagues showed that high blood levels of estradiol, a form of estrogen, at hospital admission was associated with death in critically ill patients regardless of gender.

To address how trends in estradiol over time may relate to mortality, May and colleagues measured estradiol levels in 1,408 critically ill or injured adults requiring ICU care for at least 48 hours. They report in the Journal of the American College of Surgeons that changes in blood estradiol levels in critically ill or injured adults are more strongly associated with mortality than a single estradiol measurement done at admission and outperformed other measures of inflammation.

While it remains unclear whether estradiol is contributing to disease outcome or is simply a marker of disease severity, the findings suggest that blood estradiol levels may be a clinically useful predictor of death.