Trajectory of Early Life Adiposity Among South Asian Children.

Importance: Measures of childhood adiposity merit investigation, particularly in individuals of South Asian descent. Objective: To investigate prenatal and childhood factors associated with the trajectory of adiposity in South Asian children, and the cumulative contribution of modifiable factors, such as diet and physical activity, on this trajectory. Design, Setting, and Participants: This cohort study was a prospective analysis of the South Asian Birth Cohort (START; 2011-2015) for discovery; and the Family Atherosclerosis Monitoring In Early Life (FAMILY; 2002-2009) in Ontario, Canada, and the Born in Bradford (BiB; 2008-2009) cohort in Bradford, UK, for validation. Mother-child pairs included 903 South Asian individuals (START), 675 White European individuals (FAMILY), and 1593 individuals (BiB), of which 52% were South Asian. Analysis was conducted from March 2020 to September 2024. Exposure: Maternal, infancy, and early childhood exposures. Main Outcomes and Measures: Adiposity, assessed by the sum of subscapular and triceps skinfold thicknesses (SSF) from birth to 3 years, aggregated to a single measure as total area under the growth curve (AUC for SSF); multivariable linear regression models to identify determinants of AUC for SSF; and a cumulative score to assess joint contribution of modifiable risk factors to AUC for SSF. Results: START included 903 children (456 female [50.5%]; mean [SD] maternal age, 30.2 [4.0] years; maternal mean [SD] prepregnancy body mass index [BMI], 23.8 [4.50]). Maternal sum of skinfold thicknesses (β = 0.80 [95% CI, 0.30-1.30] per 10 mm), gestational weight gain (β = 0.38 [95% CI, 0.02-0.74] per 5 kg), a health-conscious diet score (β = -0.68 [95% CI, -1.26 to -0.10] per 1 SD), and infant breastfeeding for the first year (β = -1.68 [95% CI, -2.94 to -0.42), as well as physical activity (β = -0.33 [95% CI, -0.57 to -0.09] per 30-min/d) and screen time (β = 0.49 [95% CI, 0.18-0.81] per 30-min/d) were each independently associated with AUC for SSF. These 6 early-life modifiable factors combined into a single score had a direct, graded association between number of factors and AUC for SSF (P for trend < .001). In the validation cohorts, maternal BMI, breastfeeding, and child physical activity were replicated and showed a similar graded association with AUC for SSF (P for trend < .001) when combined. Conclusions and Relevance: In this cohort study of South Asian children, 6 modifiable factors were associated with lower adiposity and combined into a single score. This score may be useful in clinical and public health settings to help mitigate childhood obesity in South Asian individuals and beyond.