Hypoglycemia in critically ill adults--association yes, causation not proven

Hypoglycemia is consistently associated with an increased risk of death in hospital patients in general, patients treated in intensive care units, and type II diabetes patients recruited to large randomized controlled trials. In 1965, Sir Austin Bradford Hill elucidated nine characteristics that help establish a causal relationship between exposure to a potentially harmful substance or event (in this context, hypoglycemia) and disease onset or death; hypoglycemia exhibits some of those characteristics but others remain to be explored. While we await data that address the outstanding issues, common sense dictates that clinicians avoid causing hypoglycemia whenever possible.