A trend analysis of childhood asthma on hospital discharges and emergency department visits from 2000-2011

Background:  Asthma in children is a leading cause of emergency department (ED) visits, hospitalizations and missed school days. It can significantly affect a child’s quality of life with bothersome daily symptoms that interfere with play, sports, sleep and school. Unfortunately, childhood asthma can only be controlled but can't be cured as yet, and symptoms may continue into adulthood. We investigated the asthma morbidity trends from 2000-2011 and seasonal pattern in childhood asthma across different age groups by race, gender and residence area.

Methods: We obtained monthly asthma discharge data on hospital discharges and ED visits from all the hospitals in South Carolina.  ICD9-CM: 493 was used to identify primary diagnosed asthma patient. Age was grouped according to pre-school, elementary-school, middle- school and high-school age-groups. Each age-group was further stratified into Male/Female, White/African-American and Rural/Urban status. The yearly and month-wise population based asthma discharge rate was then calculated.

Results: Yearly asthma rate was observed highest among pre-school (1.37%), followed by elementary (1.18%), middle (0.65%) and high school children (0.49%). The trend from 2000-2011 was seen decreasing and remained almost plateaued since 2005. Males had higher asthma rate than females in all age-groups except high school. African-American race and Rural areas had comparatively higher asthma rate in all age-groups. Specific seasonal pattern was observed in this trend analysis over a period of 11 years. Asthma discharge rate spiked from August and reached highest in September-November and was lowest in June-July.

Conclusion: Even though asthma rates have declined in all ages-groups since 2000, disparities in rates persist and deserve further study. A consistent monthly pattern in discharge rate could provide an important insight for the management of asthma in hospitals and ED.