Hospitalizations with primary versus secondary discharge diagnoses of asthma: implications for pediatric asthma surveillance.

Asthma-related hospitalizations are sentinel events in pediatric asthma surveillance. Little is known about hospitalizations that are assigned a secondary discharge diagnosis of asthma (SDDA). The National Hospital Discharge Survey (NHDS) was analyzed to compare hospitalizations with primary versus secondary discharge diagnoses of asthma. Most hospitalizations with SDDA had primary diagnoses of respiratory origin. Surveillance systems tracking the hospitalization burden of pediatric asthma should consider including selected hospitalizations with a secondary diagnosis of asthma.