Body mass index (BMI) trajectories from birth to 11.5 years: relation to early life food intake

The timing of solid introduction in an 'obesogenic' environment: a narrative review of the evidence and methodological issues

OBJECTIVE

To evaluate the evidence for association between obesity risk outcomes >12 months of age and timing of solid introduction in healthy term infants in developed countries, the large majority of whom are not exclusively breastfed to six months of age.

METHODS

Studies included were published 1990 to March 2013.

RESULTS

Twenty-six papers with weight status or obesity prevalence outcomes were identified. Studies were predominantly cohort design, most with important methodological limitations. Ten studies reported a positive association. Of these, only two were large, good-quality studies and both examined the outcome of early (<4 months) introduction of solids. None of the four good-quality studies that directly evaluated current guidelines provided evidence of any clinically relevant protective effect of solid introduction from 4-5 versus ≥6 months of age.

CONCLUSION

The introduction of solids prior to 4 months of age may result in increased risk of childhood obesity but there is little evidence of adverse weight status outcomes associated with introducing solids at 4-6 rather than at six months.

IMPLICATIONS

More and better quality evidence is required to inform guidelines on the 'when, what and how' of complementary feeding.

Growth trajectories in early childhood, their relationship with antenatal and postnatal factors, and development of obesity by age 9 years: results from an Australian birth cohort study

BACKGROUND

In an era where around one in four children in the United Kingdom, the United States, and Australia are overweight or obese, the development of obesity in early life needs to be better understood. We aimed to identify groups of children with distinct trajectories of growth in infancy and early childhood, to examine any association between these trajectories and body size at age 9, and to assess the relative influence of antenatal and postnatal exposures on growth trajectories.

DESIGN

Prospective Australian birth cohort study.

SUBJECTS AND METHODS

In total, 557 children with serial height and weight measurements from birth to 9 years were included in the study. Latent class growth models were used to derive distinct groups of growth trajectories from birth to age 3½ years. Multivariable logistic regression models were used to explore antenatal and postnatal predictors of growth trajectory groups, and multivariable linear and logistic regression models were used to examine the relationships between growth trajectory groups and body size at age 9 years.

RESULTS

We identified four discrete growth trajectories from birth to age 3½ years, characterised as low, intermediate, high, or accelerating growth. Relative to the intermediate growth group, the low group had reduced z-body mass index (BMI) (-0.75 s.d.; 95% confidence interval (CI) -1.02, -0.47), and the high and accelerating groups were associated with increased body size at age 9 years (high: z-BMI 0.70 s.d.; 95% CI 0.49, 0.62; accelerating: z-BMI 1.64 s.d.; 95% CI 1.16, 2.11). Of the antenatal and postnatal exposures considered, the most important differentiating factor was maternal obesity in early pregnancy, associated with a near quadrupling of risk of membership of the accelerating growth trajectory group compared with the intermediate growth group (odds ratio (OR) 3.72; 95% CI 1.15, 12.05).

CONCLUSIONS

Efforts to prevent childhood obesity may need to be embedded within population-wide strategies that also pay attention to healthy weight for women in their reproductive years.

Sauver JL. Health Care Utilization by Body Mass Index in a Pediatric Population

OBJECTIVE

We tested the hypothesis that the frequency of emergency department (ED) visits, outpatient clinic visits, and hospitalizations were higher among children with higher body mass index (BMI) categories, even after controlling for demographics, socioeconomic status, and presence of other chronic medical conditions.

METHODS

We obtained electronic height, weight, and utilization data for all residents of Olmsted County, Minnesota, aged 2 to 18 years on January 1, 2005 (n = 34,335), and calculated baseline BMI (kg/m(2)). At least 1 BMI measurement and permission to use medical record information was available for 19,771 children (58%); 19,528 with follow-up comprised the final cohort. BMIs were categorized into underweight/healthy weight (<85th percentile), overweight (85th to <95th percentile), and obese (≥95th percentile). Negative binomial models were used to compare the rate of utilization across BMI categories. Multivariable models were used to adjust for the effects of age, race, sex, socioeconomic status, and chronic medical conditions.

RESULTS

Compared to children with BMI <85th percentile, overweight and obese status were associated with increased ED visits (adjusted incident rate ratio [IRR] 1.16, 95% confidence interval [CI] 1.10, 1.23; and IRR 1.27, 95% CI 1.19, 1.35, respectively; P for trend <.0001), and outpatient clinic visits (IRR 1.05, 95% CI 1.02, 1.08; and IRR 1.07, 95% CI 1.04, 1.11, respectively; P for trend <.0001). No associations were observed between baseline BMI category and hospitalizations in the adjusted analyses.

CONCLUSIONS

Children who are overweight or obese utilize the ED and outpatient clinics more frequently than those who are underweight/healthy weight, but are not hospitalized more frequently.

Effects of long-term developmental patterns of adiposity on levels of C-reactive protein and fibrinogen among North-American men and women: the Spokane Heart Study

This study examined the heterogeneity in BMI development by identifying distinct developmental trajectories. These trajectories were further investigated by relating them to markers of low-grade inflammation later in life. Data from approximately 400 healthy volunteers participating in the Spokane Heart Study were collected in 2-year intervals, and four waves of data were available for the current analyses. Body weight was measured by BMI and low-grade inflammation by high-sensitivity C-reactive protein (CRP) and fibrinogen. Up to date statistical techniques, i.e., latent class growth models, were used to analyse heterogeneity in body weight, and linear regressions were run to analyse possible associations between trajectories of body weight and CRP/fibrinogen levels. Six trajectories were identified (three stable, two increasing, and one decreasing) which differed significantly on CRP/fibrinogen levels, highlighting the importance of weight trajectories. The differences were only partly explained by variations in lifestyle habits.