OBJECTIVE:

Although many studies have found that childhood levels of body mass index (BMI; kg/m(2)) are associated with adult levels, it has been reported that childhood BMI is not associated with adult adiposity. We further examined these longitudinal associations.

DESIGN:

Cohort study based on examinations between 1973 and 1996.

SETTING:

Bogalusa, Louisiana.

PARTICIPANTS:

Children (2610; ages 2-17 years old) who were followed to ages 18 to 37 years; the mean follow-up was 17.6 years.

MAIN OUTCOME MEASURES:

BMI-for-age and triceps skinfold thickness (SF) were measured in childhood. Subscapular and triceps SFs were measured among adults, and the mean SF was used as an adiposity index. Adult obesity was defined as a BMI >or= 30 kg/m(2) and adult overfat as a mean SF in the upper (gender-specific) quartile.

RESULTS:

Childhood levels of both BMI and triceps SF were associated with adult levels of BMI and adiposity. The magnitude of these longitudinal associations increased with childhood age, but the BMI levels of even the youngest (ages 2-5 years) children were moderately associated (r = 0.33-0.41) with adult adiposity. Overweight (BMI-for-age >or= 95th centile) 2- to 5-year-olds were >4 times as likely to become overfat adults (15 of 23 [65%]), as were children with a BMI < 50th centile (30 of 201 [15%]). Even after accounting for the triceps SF of children, BMI-for-age provided additional information on adult adiposity.

CONCLUSIONS:

Childhood BMI is associated with adult adiposity, but it is possible that the magnitude of this association depends on the relative fatness of children.