BMI trajectories in early life predict cardiometabolic outcomes later in childhood
Trajectories of body mass index z-scores (BMIz) during the first 2 years of life predict cardiometabolic parameters later in childhood, a new study from Singapore has found.
“We have identified four distinct BMIz trajectories in the first 2 years of life in a multi-ethnic cohort of Asian children. We observed ethnic-specific differences and several factors predictive of the BMIz trajectories,” the researchers said.
“Our findings suggest that different BMIz trajectories in the first 2 years reflect differential changes in body composition (fat vs lean mass) and are more predictive of body composition and obesity in later childhood than a single time point assessment of BMIz at 2 years,” they added.
Investigators found that the 1,170 participating children fell within one of four distinct BMIz trajectories: normal (73.2 percent), stable low (13.2 percent), stable high (8.6 percent) and rapid BMIz gain (5.0 percent). [Sci Rep 2017;7:8424]
Ethnicity and other birth circumstances played a substantial role in predicting the odds of belonging in a particular BMIz trajectory, with those of Indian ethnicity having higher chances of being in the stable low trajectory (odds ratio [OR], 2.36; 95 percent CI, 1.54 to 3.63) than those of Chinese ethnicity.
Similarly, children of Malay (OR, 3.49; 1.48 to 8.25) or Indian (OR, 6.30; 2.66 to 14.73) ethnicity had higher chances of being in the rapid BMIz gain trajectory than those of Chinese ethnicity. On the other hand, infants born to multiparous mothers had higher chances of being in the stable high trajectory (OR, 1.67; 1.07 to 2.61).
Compared with the normal BMIz trajectory, the stable low trajectory was significantly associated with lower waist-to-height ratio (WHtR; β, -0.02; -0.03 to -0.01), sum of skinfolds (SSF; β, -0.43; -0.62 to -0.24), fat mass index (FMI; β, -0.55; -0.94 to -0.15) and lean mass index (LMI; β, -0.68; -1.07 to -0.29) after controlling for potential confounders.
Stable low BMIz trajectory was also associated with lower systolic (SBP; β, -2.86 mmHg; -4.92 to -0.80) and diastolic (DBP; β, -1.61 mmHg; -3.01 to -0.20) blood pressures.
In contrast, both the stable high and rapid gain trajectories were associated with higher WHtR and SSF, while only the stable high trajectory was correlated with higher LMI and only the rapid gain was associated with higher FMI.
Investigators recruited 1,170 pregnant women (mean age 30.7±5.1 years) with singleton deliveries from the growing up in Singapore towards healthy outcomes study. Only those with no history of chemotherapy or psychotropic drugs, and who did not have diabetes mellitus were included.
Infant anthropometric measurements were collected at 3, 6, 9, 12, 15 and 18 months, and at 2 and 5 years. Child SBP and DBP were measured at 5 years to determine the presence of prehypertension.
According to the researchers, the development of the BMIz trajectories will help with determining high-risk individuals and in improving the understanding of cardiometabolic diseases.
“[T]he predictors of early childhood BMIz trajectories, especially modifiable ones (eg, prepregnancy BMI and gestational weight gain), may help in developing effective preventive clinical and public health interventions for cardiometabolic disease,” they added.