Association Between Markers of Adiposity During Childhood and Puberty Onset in Latino Girls.

CONTEXT: Prepubertal adiposity is associated with earlier puberty. It is unclear when this association starts, if all adiposity markers are similarly associated, and whether all pubertal milestones are similarly affected.

OBJECTIVE: To evaluate the association between different adiposity markers during childhood and the timing of different pubertal milestones in Latino girls.

DESIGN, SETTING, AND PARTICIPANTS: Longitudinal follow-up of 539 female participants of the Chilean Growth and Obesity Cohort recruited from childcare centers (mean age 3.5 years) from the southeast area of Santiago, Chile. Participants were singletons born between 2002 and 2003 within the normal birthweight range. Since 2006, a trained dietitian measured weight, height, waist circumference (WC) and skinfolds to estimate body mass index (BMI) Centers for Disease Control and Prevention percentiles, central obesity, percentage of fat mass (%FM), and fat mass index (FMI, fat mass/height2).

MAIN OUTCOME: Since 2009, sexual maturation was assessed every 6 months to assess age at (1) thelarche, (2) pubarche, (3) menarche, and (4) peak height velocity (PHV).

RESULTS: At thelarche, 12.5% were obese and 2% had central obesity. The median age of pubarche, menarche, and PHV were all associated with markers of adiposity at different time points during childhood whereas thelarche only with %FM and FMI. Adiposity clusters models showed that children with trajectories of high WC, %FM, and FMI during childhood were related with earlier thelarche, pubarche, menarche, and PHV but BMI trajectories only with menarche and PHV.

CONCLUSIONS: Higher WC, %FM, and FMI were associated with earlier age at thelarche, pubarche, menarche, and PHV. The effect of BMI was less consistent.