Childhood Body Mass Index Trajectories, Adult-Onset Type 2 Diabetes and Obesity-Related Cancers
Menée à partir de données du registre de santé scolaire de Copenhague portant sur 301 927 enfants (âge : 6-15 ans), cette étude analyse l'association entre la trajectoire de l'indice de masse corporelle chez l'enfant et le risque de cancer lié à l'obésité chez l'adulte, ainsi que l'effet du diabète de type 2 sur cette association
Résumé en anglais
Elevated childhood body mass index (BMI), commonly examined as a ‘once-only’ value, increases the risk of cancer and type 2 diabetes (T2D) in adulthood. Continuous exposure to adiposity during childhood may further increase cancer risk. We examined whether longitudinal childhood BMI trajectories were associated with adult obesity-related cancer and the role of adult-onset T2D in these associations.Five sex-specific latent class BMI trajectories were generated for 301,927 children (149,325 girls) aged 6-15 years from the Copenhagen School Health Records Register. Information on obesity-related cancers and T2D was obtained from national health registers. Incidence rate ratios (IRR), cumulative incidences and confidence intervals (CI) were estimated using Poisson regressions.Compared to the average childhood BMI trajectory (approximately 40% of individuals), the rate of obesity-related cancer (excluding breast cancer) increased with higher childhood BMI trajectories among women. The highest rates occurred in the overweight (IRR = 1.27, 95% CI : 1.17-1.38) and obesity (IRR = 1.79, 95% CI : 1.53-2.08) BMI trajectories. Similar patterns were observed among men. In contrast, women with the obesity childhood BMI trajectory had the lowest rate of pre- and post-menopausal breast cancer (IRR = 0.59, 95% CI: 0.43-0.80 and IRR = 0.41, 95% CI: 0.30-0.57, respectively). For all trajectories, the cumulative risk of obesity-related cancer increased with adult-onset T2D.Consistent childhood overweight or obesity may increase the rates of adult obesity-related cancer and decrease the rates of breast cancer. Adult-onset T2D conferred additional risk for obesity-related cancer, but the effect did not differ across childhood BMI trajectories.
