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Early life growth trajectories and future risk for overweight.

Jones-Smith JC, Neufeld LM, Laraia B, Ramakrishnan U, Garcia-Guerra A, Fernald LC - Nutr Diabetes (2013)

Bottom Line: The SITAR models use a nonlinear random-effects model to estimate an average growth curve for BMI, length and weight and each participant's deviation from this curve on three dimensions-size, velocity and timing of peak velocity.Associations for timing of peak velocity varied by anthropometric measure.However, in the mutually adjusted models, only relative BMI/length/weight (size) remained statistically significant.

View Article: PubMed Central - PubMed

Affiliation: Department of International Health (Human Nutrition), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.

ABSTRACT

Objective: Standard approaches have found that rapid growth during the first 2 years of life is a risk factor for overweight in later childhood. Our objective was to test whether growth velocity, independent of concurrent size, was associated with overweight using a nonlinear random-effects model that allows for enhanced specifications and estimations.

Methods: Longitudinal data from a birth cohort in Mexico (n=586) were used to estimate growth trajectories over 0-24 months for body mass index (BMI), length and weight using the SuperImposition by Translation and Rotation (SITAR) models. The SITAR models use a nonlinear random-effects model to estimate an average growth curve for BMI, length and weight and each participant's deviation from this curve on three dimensions-size, velocity and timing of peak velocity. We used logistic regression to estimate the association between overweight status at 7-9 years and size, velocity and timing of BMI, length and weight trajectories during 0-24 months. We tested whether any association between velocity and overweight varied by relative size during 0-24 months or birth weight.

Results: SITAR models explained the majority of the variance in BMI (73%), height (86%) and weight (85%) between 0-24 months. When analyzed individually, relative BMI/length/weight (size) and BMI/length/weight velocity during 0-24 months were each associated with increased odds of overweight in late childhood. Associations for timing of peak velocity varied by anthropometric measure. However, in the mutually adjusted models, only relative BMI/length/weight (size) remained statistically significant. We found no evidence that any association between velocity and overweight varied by size during 0-24 months or birth weight.

Conclusions: After mutual adjustment, size during 0-24 months of life (as opposed to birth size), but not velocity or timing of peak velocity, was most consistently associated with overweight in later childhood.

No MeSH data available.


Related in: MedlinePlus

Average growth curve (solid line) of each SITAR parameter: (1) size, (2) velocity, (3) timing of peak velocity; (a) BMI trajectory, (b) height trajectory, (c) weight trajectory. The s.ds. are displayed as dashed lines. Values for s.ds. in the BMI models were: 1.21 kg m−2 for size, 0.25 fractional units for velocity, 0.56 months for timing; in height models: 2.49 cm, 0.12 fractional units, 1.0 months; in weight models: 1 kg, 0.14 fractional units, 1.14 months.
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fig1: Average growth curve (solid line) of each SITAR parameter: (1) size, (2) velocity, (3) timing of peak velocity; (a) BMI trajectory, (b) height trajectory, (c) weight trajectory. The s.ds. are displayed as dashed lines. Values for s.ds. in the BMI models were: 1.21 kg m−2 for size, 0.25 fractional units for velocity, 0.56 months for timing; in height models: 2.49 cm, 0.12 fractional units, 1.0 months; in weight models: 1 kg, 0.14 fractional units, 1.14 months.

Mentions: The SITAR models explained a very large portion of the variance in BMI, height and weight between 0–24 months (73, 86 and 85%, respectively). For comparison, a model that includes only birth BMI and change in BMI from 0–24 months explained only 44% of the variance in BMI. The estimated average growth trajectories from the SITAR models for BMI, length and weight are displayed in Figure 1. The s.ds. of the random-effect SITAR parameters (that is, size, velocity, timing) describe the degree of variation around the sample average curve and are shown in dashed lines in Figure 1 (+/−1 s.d.). Of note, the timing of peak velocity (panels 1a, 2b, 3c), which shifts the entire curve left or right, would have different consequences for BMI compared with length and weight due to different curve shapes. For BMI, earlier timing of peak velocity (lower values for timing) would result in an earlier decrease in BMI-for-age. For length and weight, earlier timing of peak velocity would result in an earlier increase in length/weight-for-age.


Early life growth trajectories and future risk for overweight.

Jones-Smith JC, Neufeld LM, Laraia B, Ramakrishnan U, Garcia-Guerra A, Fernald LC - Nutr Diabetes (2013)

Average growth curve (solid line) of each SITAR parameter: (1) size, (2) velocity, (3) timing of peak velocity; (a) BMI trajectory, (b) height trajectory, (c) weight trajectory. The s.ds. are displayed as dashed lines. Values for s.ds. in the BMI models were: 1.21 kg m−2 for size, 0.25 fractional units for velocity, 0.56 months for timing; in height models: 2.49 cm, 0.12 fractional units, 1.0 months; in weight models: 1 kg, 0.14 fractional units, 1.14 months.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3584986&req=5

fig1: Average growth curve (solid line) of each SITAR parameter: (1) size, (2) velocity, (3) timing of peak velocity; (a) BMI trajectory, (b) height trajectory, (c) weight trajectory. The s.ds. are displayed as dashed lines. Values for s.ds. in the BMI models were: 1.21 kg m−2 for size, 0.25 fractional units for velocity, 0.56 months for timing; in height models: 2.49 cm, 0.12 fractional units, 1.0 months; in weight models: 1 kg, 0.14 fractional units, 1.14 months.
Mentions: The SITAR models explained a very large portion of the variance in BMI, height and weight between 0–24 months (73, 86 and 85%, respectively). For comparison, a model that includes only birth BMI and change in BMI from 0–24 months explained only 44% of the variance in BMI. The estimated average growth trajectories from the SITAR models for BMI, length and weight are displayed in Figure 1. The s.ds. of the random-effect SITAR parameters (that is, size, velocity, timing) describe the degree of variation around the sample average curve and are shown in dashed lines in Figure 1 (+/−1 s.d.). Of note, the timing of peak velocity (panels 1a, 2b, 3c), which shifts the entire curve left or right, would have different consequences for BMI compared with length and weight due to different curve shapes. For BMI, earlier timing of peak velocity (lower values for timing) would result in an earlier decrease in BMI-for-age. For length and weight, earlier timing of peak velocity would result in an earlier increase in length/weight-for-age.

Bottom Line: The SITAR models use a nonlinear random-effects model to estimate an average growth curve for BMI, length and weight and each participant's deviation from this curve on three dimensions-size, velocity and timing of peak velocity.Associations for timing of peak velocity varied by anthropometric measure.However, in the mutually adjusted models, only relative BMI/length/weight (size) remained statistically significant.

View Article: PubMed Central - PubMed

Affiliation: Department of International Health (Human Nutrition), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.

ABSTRACT

Objective: Standard approaches have found that rapid growth during the first 2 years of life is a risk factor for overweight in later childhood. Our objective was to test whether growth velocity, independent of concurrent size, was associated with overweight using a nonlinear random-effects model that allows for enhanced specifications and estimations.

Methods: Longitudinal data from a birth cohort in Mexico (n=586) were used to estimate growth trajectories over 0-24 months for body mass index (BMI), length and weight using the SuperImposition by Translation and Rotation (SITAR) models. The SITAR models use a nonlinear random-effects model to estimate an average growth curve for BMI, length and weight and each participant's deviation from this curve on three dimensions-size, velocity and timing of peak velocity. We used logistic regression to estimate the association between overweight status at 7-9 years and size, velocity and timing of BMI, length and weight trajectories during 0-24 months. We tested whether any association between velocity and overweight varied by relative size during 0-24 months or birth weight.

Results: SITAR models explained the majority of the variance in BMI (73%), height (86%) and weight (85%) between 0-24 months. When analyzed individually, relative BMI/length/weight (size) and BMI/length/weight velocity during 0-24 months were each associated with increased odds of overweight in late childhood. Associations for timing of peak velocity varied by anthropometric measure. However, in the mutually adjusted models, only relative BMI/length/weight (size) remained statistically significant. We found no evidence that any association between velocity and overweight varied by size during 0-24 months or birth weight.

Conclusions: After mutual adjustment, size during 0-24 months of life (as opposed to birth size), but not velocity or timing of peak velocity, was most consistently associated with overweight in later childhood.

No MeSH data available.


Related in: MedlinePlus