Objectives: To compare health care utilization and expenditures for healthy-weight patients, overweight patients, and patients with diagnosed and undiagnosed obesity and to examine factors associated with a diagnosis of obesity.
Design: Retrospective study using claims data from a large pediatric integrated delivery system.
Setting: An urban academic children's hospital.
Participants: Children aged 5 to 18 years who presented to a primary care clinic for well-child care visits during the calendar years 2002 and 2003 and who were followed up for 12 months.
Main outcome measures: Diagnosis of obesity, primary care visits, emergency department visits, laboratory use, and health care charges.
Results: Of 8404 patients, 57.9% were 10 years or older, 61.2% were African American, and 72.9% were insured by Medicaid. According to the criteria of body mass index (calculated as weight in kilograms divided by the square of height in meters), 17.8% were overweight and 21.9% were obese. Of the obese children, 42.9% had a diagnosis of obesity. Increased laboratory use was found in both children with diagnosed obesity (odds ratio [OR], 5.49; 95% confidence interval [CI], 4.65-6.48) and children with undiagnosed obesity (OR, 2.32; 95% CI, 1.97-2.74), relative to the healthy-weight group. Health care expenditures were significantly higher for children with diagnosed obesity (adjusted mean difference, $172; 95% CI, $138-$206) vs the healthy-weight group. Factors associated with the diagnosis of obesity were age 10 years and older (OR, 2.7; 95% CI, 2.0-3.4), female sex (OR, 1.5; 95% CI, 1.2-1.8), and having Medicaid (OR, 1.6; 95% CI, 1.1-2.3).
Conclusions: Increased health care utilization and charges reported in obese adults are also present in obese children. Most children with obesity had not been diagnosed as having obesity in this administrative data set.