To determine the relationship between routine screening for cholesterol level and subsequent change in body mass index (BMI; calculated as weight in kilograms divided by height in meters squared).
General pediatrics clinics at 2 academic centers.
Adolescents with BMIs in the 85th percentile or higher aged 10 to 18 years whose cholesterol levels were screened between June 2003 and June 2005 and controls matched for age, sex, ethnicity, and BMI.
The primary outcome was the “best” individual BMI change following screening. The secondary outcome was the trend of BMI change during follow-up.
Sixty-four matched pairs met the inclusion criteria (N = 128). Subjects were followed up for 3 to 30 months after identification (mean [SD], 18  months). The mean BMI changes for screened subjects did not differ from those of unscreened subjects (−0.33 vs −0.34; P = .97). However, age at time of enrollment significantly modified the results (P = .02). After cholesterol screening, younger subjects initially increased in BMI, while older subjects initially decreased. The overall trend of individual BMI change increased during the follow-up period and was not significantly different between the 2 groups (likelihood ratio test, 0.9; P = .64).
Cholesterol screening of overweight and obese adolescents is not associated with short-term BMI change, though age at time of screening modified subsequent BMI change. Clinicians should not assume that screening will help motivate weight loss, though the effect of age at the time of screening deserves further research.