Monthly variation in pediatric visits for headache to US emergency departments

Headache is a common pediatric symptom often associated with stress and fatigue which may be more common during the school year. The purpose of this study is to determine if visits for headache are more common during the months of the school year. This study is a secondary analysis of the National Hospital Ambulatory Medical Care Survey (NHAMCS) database from 2001 to 2010. Patient visits in those aged 18 years or younger not associated with injury were examined. Only visits with an International Classification of Diseases, ninth revision (ICD-9) code consistent with headache were included. Data were analyzed using cumulative binomial probabilities. This statistic was used to establish the chance of seeing up to the observed number of visits for headache in a given month assuming that all months have an equal number of visits. A total of 660 unweighted visits representing 3.2 million patient encounters met the inclusion and exclusion criteria. Visits for headache were more common during the months of January, September, and October and less common in March, April, July, and November. Subgroup analysis was performed for children aged 13-18years. In this subgroup, headaches were more common in January, September, and October. They were less common in July and December. Headache is more common during the first 2months back to school in the fall as well as after the winter break in January. While we are not able to establish causality, we propose that children with headache require additional attention during the school year, particularly in the months following summer and winter breaks.