Abstract
OBJECTIVES:
To examine the associations among birth weight, infant growth and childhood adiposity, and to test whether parental weight status modifies these associations.
METHODS:
The sample was comprised of 423 participants born at term who were an appropriate size for their gestational age from the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study, a cohort of 630 children with a parental history of obesity. Infant growth velocity from zero to two years of age was estimated using slopes from simple linear regression for weight and body mass index (BMI) Z-scores. Child anthropometrics and body composition, and parental BMI were measured from eight to 10 years of age. Associations were modelled using multiple linear regressions.
RESULTS:
Increased birth weight and growth velocity independently predicted increased childhood adiposity. Effects of infant growth velocity on later adiposity were stronger with higher maternal BMI but not with higher paternal BMI. Similar interactions with birth weight were not found.
CONCLUSIONS:
Early childhood measures of growth and the mother’s BMI score should be included in investigations on obesity risk.
Keywords: Adiposity, Body mass index, Cohort study, Dual-energy x-ray absorptiometry, Parents, Weight gain
Abstract
OBJECTIFS :
Examiner les associations entre le poids à la naissance, la croissance du nourrisson et l’adiposité pendant l’enfance et vérifier si le poids des parents les modifie.
MÉTHODOLOGIE :
L’échantillon se composait de 423 participants nés à terme dont la taille correspondait à l’âge gestationnel et qui étaient extraits de l’étude QUALITY sur l’adiposité et le mode de vie chez les jeunes du Québec, menée auprès d’une cohorte de 630 enfants ayant des antécédents parentaux d’obésité. Les chercheurs ont estimé la vélocité de croissance des nourrissons de zéro à deux ans au moyen de l’écart réduit de la régression linéaire simple et de l’indice de masse corporelle (IMC). Ils ont mesuré les données anthropométriques et la composition corporelle des enfants de huit à dix ans, ainsi que l’IMC des parents. Ils ont établi les modèles d’association au moyen de régressions linéaires multiples.
RÉSULTATS :
Un poids de naissance et une vélocité de croissance élevés étaient des prédicteurs indépendants d’une adiposité plus importante pendant l’enfance. Les effets de la vélocité de croissance des nourrissons sur leur adiposité plus tard étaient plus marqués lorsque l’IMC de la mère, mais pas celui du père, était élevé. Les chercheurs n’ont constaté aucune interaction similaire par rapport au poids à la naissance.
CONCLUSIONS :
Il faudrait inclure les mesures de croissance de la petite enfance et l’IMC de la mère dans les explorations du risque d’obésité.
Over the past two decades, the prevalence of overweight and obesity has almost tripled among paediatric populations in North America. Several risk factors, including genetic, behavioural, environmental and social conditions have been associated with childhood obesity. Studies have also identified birth weight and the rate of weight gain in the first months and years of life as risk factors for excess weight during childhood (1,2).
Despite numerous studies, it remains unclear whether birth weight or postnatal growth are most strongly associated with the development of childhood obesity. This may be due to variations across studies with respect to intrauterine conditions that manifest through measures of birth weight, length and gestational age; the period during which postnatal growth is measured and the definition of postnatal growth velocity; the age at which childhood adiposity is measured and the types of measures used (ie, anthropometry versus direct measurement of body composition); and population characteristics including genetic background and lifestyle habits. Moreover, few studies have examined the combined effect of both birth weight and postnatal growth velocity (ie, being born heavy and gaining weight rapidly during infancy) on later adiposity, specifically among children who were born at an appropriate size for their gestational age (3–5).
Obesity tends to aggregate within families, with children’s likelihood of being obese increasing with the number of obese parents (6). Parents may influence their child’s likelihood of becoming obese through genetic predispositions, epigenetic modifications and genomic imprinting (7), as well as through shared lifestyle habits (8). Studies have reported associations among maternal weight, a child’s birth weight and the child’s subsequent weight (7,9); others have reported associations between paternal weight and children’s postnatal weight. However, it remains unclear whether, and to what extent, parental weight status modifies associations between their child’s early life growth and later adiposity (10–12).
The current study was conducted in a sample of Caucasian children born at term who were an appropriate size for their gestational age, with a parental history of obesity. Specifically, our objectives were to examine the relationship among birth weight, growth in the first two years of life and indicators of adiposity at eight to 10 years of age; to determine whether and how parental weight status modifies the association among birth weight, infant growth and adiposity at eight to 10 years of age; and to determine whether birth weight modifies the association between infant growth and adiposity at eight to 10 years of age.
METHODS
Participants were drawn from the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study, an ongoing longitudinal investigation of the natural history of obesity and cardiovascular risk factors in Caucasian youth. Children (n=630) and their biological parents (n=1260) were recruited through elementary schools located within a 75 km radius of three major urban centres in Quebec: Montreal, Quebec City and Sherbrooke. Eligibility criteria required participants to be Caucasian, eight to 10 years of age at recruitment, with both biological parents available for the study and at least one parent being obese based on standard definitions of body mass index (BMI) and waist circumference (ie, BMI ≥30 kg/m2 and/or waist circumference ≥102 cm in men and ≥88 cm in women). At baseline, families were invited for a clinic visit during which questionnaires were completed, and biological and physiological measurements were obtained. Written informed consent was obtained from the parents, and assent was provided by the children. The Ethics Review Boards of CHU Sainte Justine (Montreal, Quebec) and Laval University (Laval, Quebec) approved the study. A detailed description of the study design and data collection methods are available (13). For the current analyses, a subsample of QUALITY (n=423) participants who were born at term (37 to 42 weeks’ gestation), with appropriate birth weight and length (between the 3rd and 97th sex- and gestational age-specific percentile based on the Centers for Disease Control and Prevention [CDC, Georgia, USA] intrauterine growth curves) (14), and complete data were used.
Measurements from zero to two years
Birth weight and length, gestational age, and later measurements of weight and length collected from one to 24 months of age, were obtained from the ‘Health Booklet’ issued to all Quebec parents of newborn children, which is subsequently completed during routine medical visits. Participants had a minimum of three measurement times each; the median number of measurement times was seven (range three to 11). Measures of weight and length were transformed to age- and sex-specific BMI and weight Z-scores using WHO growth standards (15). Individual slopes for BMI and weight from zero to two years of age were estimated and used as measures of the rate of infant growth.
Measurements at eight to 10 years of age
Height, weight and waist circumference were measured according to standard protocols (13). BMI was calculated as weight (kg) divided by height squared (m2), and BMI Z-scores were computed using WHO growth standards (16). Waist-to-height ratio was computed as waist circumference (cm) divided by height (cm). Total lean mass, total fat mass and central fat (trunk fat) mass were measured by dual-energy x-ray absorptiometry (DEXA). The fat-free mass index (FFMI) and the fat mass index (FMI) were computed by dividing total lean mass and fat mass, respectively, by height squared (m2) (17). Trunk fat mass was estimated using the DEXA automatic region that consists of the chest, abdomen and pelvic area; the ribs, spine and pelvis (also included in this region) have been shown to have minimal influence on the measurement of trunk soft tissue (18). The percentage of central-to-total body fat was calculated (trunk fat mass/total fat mass × 100). Finally, the percentage of body fat was calculated (total fat mass/total body mass × 100). Because the methods used to estimate adiposity in children vary in accuracy, the use of multiple methods, including both anthropometric and DEXA measures, is relevant notably for comparison purposes between measures of associations and between studies. Pubertal development stage was assessed by a nurse using the five-stage Tanner scales (19,20), and was dichotomized as pre-pubertal (Tanner 1) versus puberty initiated (Tanner >1).
Parents’ measurements
Both parents’ weight and height were measured during the clinic visit using the same protocol used in children, and their BMI was calculated (kg/m2). Potential confounders examined in the associations of interest were collected in parent-administered questionnaires including parental educational attainment (at least one parent with secondary school or less, at least one parent with technical/vocational/trade degree, at least one parent with university degree), gestational diabetes, smoking or hypertension during pregnancy, and the age of mother at conception of child.
Statistical analyses
For each child, age- and sex-specific length and weight Z-scores measured between zero and two years of age were used to estimate individual slopes for BMI and weight using simple linear regressions with age in months as the independent variable. These slopes represent the predicted rate of growth in BMI and weight Z-scores over one month during the first two years of life (ie, infant growth rate). Multiple linear regressions were used to examine the effect of BMI Z-score at birth and BMI Z-score slope, and the effect of birth weight Z-scores and weight Z-score slope on adiposity. To facilitate interpretation of the beta coefficients associated with the slope variables, these variables were rescaled by multiplying slope values by 50, such that each unit corresponded to a change of approximately 0.5 SDs for 24 months (equivalent to 0.02 units in Z-scores per month).
Several sets of models were estimated. First, the effects of measurements at birth (BMI- and weight-at-birth Z-scores) and measurements of infant growth (slopes for BMI and weight Z-scores) on each outcome were examined; measurements at birth and of infant growth were entered simultaneously in two separate sets of models (ie, one for BMI measures and one for weight measures). Then age, sex and Tanner stage were additionally controlled for in each set of models. Other potential confounders were only retained in the models if they produced ≥10% change in the beta coefficients associated with measurements at birth or infant growth. Finally, interactions among BMI-at-birth, weight-at-birth, infant growth (slopes) and the mother’s and father’s BMI when the child was between eight to 10 years of age were examined by adding interaction terms one at a time to the adjusted models. Interactions between measurements at birth and measurements of infant growth (slopes) were also examined in the same way; they were considered statistically significant if the interaction term was associated with outcome variables at P≤0.05. Analyses were conducted using SAS version 9.2 (SAS Institute Inc, USA).
RESULTS
The characteristics of the participants (235 boys and 188 girls) are shown in Table 1. In the subsample, 50.4% of fathers and 42.4% of mothers were obese based on BMI cut-offs, and 39.1% of fathers and 61.1% of mothers had abdominal obesity as defined by waist circumference cut-offs. Overall, the characteristics of children included in the current analysis did not differ from those of the entire QUALITY cohort (n=630) (13).
TABLE 1.
Characteristics of the study population from the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) cohort (n=423 children)
| Characteristics | |
|---|---|
| Parents | |
| Highest level of education of either parent, n (%) | |
| Two parents with high school degree or less | 31 (7.33) |
| One or two parents with technical degree | 161 (38.06) |
| One or two parents with university degree | 231 (54.61) |
| Mother’s BMI, kg/m2 | 29.20±6.63 |
| Father’s BMI, kg/m2 | 30.68±5.45 |
| Children at birth | |
| Gestational age, weeks | 39.59±1.14 |
| BMI Z-score at birth | 0.0021±1.047 |
| Weight Z-score at birth | 0.48±0.86 |
| Slope for BMI Z-scores, zero to two years of age | 0.046±0.065 |
| Slope for weight Z-scores, zero to two years of age | 0.032±0.060 |
| Children at eight to ten years of age | |
| Child’s age, years | 9.57±0.92 |
| Female sex, n (%) | 188 (44.44) |
| Tanner stage, n (%) | |
| Tanner stage 1 | 328 (77.73) |
| Tanner stage >1 | 94 (22.27) |
| Anthropometry | |
| Age- and sex-adjusted BMI Z-score | 0.95±1.37 |
| Waist circumference, cm | 66.91±11.73 |
| Waist to height ratio | 0.48±0.073 |
| Body composition* | |
| Fat mass index, kg/m2 | 5.30±3.31 |
| % total body fat mass | 25.90±10.75 |
| % central-to-total fat mass | 40.61±5.41 |
| Fat-free mass index, kg/m2 | 13.07±1.23 |
Data presented as mean ± SD, unless otherwise indicated.
Body composition was determined using dual-energy, x-ray absorptiometry. BMI Body mass index
Measurements at birth and childhood adiposity
Both birth BMI and weight Z-scores were positively associated with adiposity measured using either anthropometry or DEXA, with the exception of per cent central-to-total body fat (Table 2). Findings remained largely unchanged before and after controlling for the child’s age, sex and Tanner stage. Beta coefficients were very similar for both sets of associations (ie, those between birth weight Z-scores or birth BMI Z-scores and later adiposity). While measurements at birth were not associated with per cent central-to-total body fat, positive associations were found for indices of central adiposity including waist circumference and waist-to-height ratio. Positive associations between measurements at birth and later lean body mass (ie, FFMI) were also found.
TABLE 2.
Associations between measurements of growth from zero to two years of age and measurements of adiposity at eight to 10 years of age in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY cohort
|
Beta coefficient* ± SE, P
|
|||||||
|---|---|---|---|---|---|---|---|
|
Body composition* at eight to 10 years of age
|
|||||||
| Anthropometry at eight to 10 years of age | Fat mass | Lean mass | |||||
|
|
|
|
|||||
| BMI Z-score | Waist circumference, cm | Waist-to-height ratio | Fat mass index, kg/m2 | % Body fat | % Central-to-total fat | Fat-free mass index, kg/m2 | |
| Model | |||||||
| Early BMI Z-scores† | |||||||
| BMI Z-score at birth | 0.35±0.065, <0.001 | 2.18±0.54, <0.001 | 0.014±0.0035, <0.001 | 0.63±0.16, <0.001 | 1.59±0.50, 0.002 | 0.19±0.26, 0.48 | 0.35±0.052, <0.001 |
| Slope for BMI Z-scores from zero to two years of age (0.02 units) | 0.15±0.021, <0.001 | 1.19±0.17, <0.001 | 0.0072±0.0011, <0.001 | 0.31±0.050, <0.001 | 0.90±0.16, <0.001 | 0.38±0.085, <0.001 | 0.12±0.017, <0.001 |
| Early Weight Z-score† | |||||||
| Weight Z-score at birth | 0.41±0.078, <0.001 | 2.87±0.64, <0.001 | 0.012±0.0043, <0.001 | 0.67±0.19, <0.001 | 1.85±0.60, 0.002 | 0.34±0.32, 0.29 | 0.39±0.064, <0.001 |
| Slope for weight Z-scores from zero to two years of age (0.02 units) | 0.16±0.022, <0.001 | 1.40±0.18, <0.001 | 0.0064±0.0012, <0.001 | 0.33±0.054, <0.001 | 1.00±0.17, <0.001 | 0.45±0.090, <0.001 | 0.11±0.018, <0.001 |
Beta coefficients represent the increase or decrease in units of each outcome variable for a one unit increase in the corresponding independent variable.
Body composition was determined using dual-energy x-ray absorptiometry;
Measures at birth and measures of infant growth were entered simultaneously in separate models for measurements of body mass index (BMI Z-scores and weight Z-scores, for each outcome variable. Models were further adjusted for the child’s age, sex and Tanner stage at eight to 10 years of age
Infant growth and childhood adiposity
Increasing slopes in BMI and weight Z-scores between zero and two years of age predicted increased adiposity at eight to 10 years of age irrespective of the indices used to assess adiposity (anthropometry or DEXA), and independently of BMI and weight at birth (Table 2). Beta coefficients were very similar when using either BMI or weight Z-score slopes as predictors of adiposity. Moreover, while measurements at birth were not statistically significantly associated with per cent central-to-total body fat at eight to 10 years of age, infant growth was positively associated with the latter. Similar results were found for waist circumference and waist-to-height ratio. Positive associations between infant growth and lean body mass were also found, with a 0.1 kg/m2 increase in FFMI for every 0.5 SD increase in BMI and weight Z-scores between zero to two years of age.
Influence of parental weight status
Statistically significant interactions were found between BMI Z-score slopes and maternal BMI for waist circumference (P=0.03), waist-to-height ratio (P=0.01) and FMI (P=0.01) at eight to 10 years of age (Table 3). Overall, with increasing maternal BMI, at a child’s age of eight to 10 years, associations between infant growth and adiposity indices increased (Figure 1 and Supplemental Tables S1 and S2). Figure 1 shows that the strength of the association between growth in the first two years of life and FMI at eight to 10 years of age increases steadily for every additional 5 kg/m2 of maternal BMI. Results were similar, albeit weaker, for interactions between weight Z-score slopes and maternal BMI. No statistically significant interactions were found between measurements at birth and maternal BMI on adiposity as well as between measurements at birth or measurements of infant growth from zero to two years of age and paternal BMI on later adiposity (all P>0.05). Similarly, no statistically significant interactions were found between measurements at birth and measurements of infant growth (P>0.05) on adiposity at eight to 10 years of age.
TABLE 3.
Interactions among maternal weight status and measurements of growth from zero to two years of age on adiposity at eight to 10 years of age in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) cohort
|
Beta coefficient* ± SE, P
|
|||
|---|---|---|---|
|
Adiposity at eight to 10 years of age
|
|||
| Waist circumference, cm | Waist-to-height ratio | Fat mass index, kg/m2 | |
| Early BMI Z-scores* | |||
| BMI Z-score at birth | 1.93±0.52, <0.001 | 0.012±0.0034, <0.001 | 0.54±0.15, <0.001 |
| Slope for BMI Z-scores from zero to two years of age (0.02 units) | −0.33±0.69, 0.63 | −0.0038±0.0044, 0.4 | −0.19±0.20, 0.35 |
| Maternal BMI by slope for BMI Z-scores zero to two years of age (0.02 units) | 0.050±0.023, 0.028 | 0.00036±0.00015, 0.014 | 0.016±0.0065, 0.012 |
| Maternal BMI (kg/m2) | 0.30±0.089, <0.001 | 0.0023±0.00057, <0.001 | 0.10±0.026, <0.001 |
| Early weight Z-score* | |||
| Weight Z-score at birth | 2.72±0.61, <0.001 | 0.011±0.0041, 0.095 | 0.63±0.18, <0.001 |
| Slope for weight Z-scores zero to two years of age (0.02 units) | −0.0018±0.81, 1 | −0.0029±0.0054, 0.59 | −0.052±0.24, 0.83 |
| Maternal BMI by slope for weight Z-scores zero to two years of age (0.02 units) | 0.048±0.026, 0.068 | 0.00032±0.00017, 0.067 | 0.013±0.0077, 0.093 |
| Maternal BMI (kg/m2) | 0.39±0.080, <0.001 | 0.0029±0.00053, <0.001 | 0.13±0.024, <0.001 |
Beta coefficients represent the increase or decrease in units of each outcome variable for a one unit increase in the corresponding independent variable.
Measures at birth, measures of infant growth, and interaction term between measures of growth and mother’s body mass index (BMI) are entered simultaneously in separate models for BMI Z-scores (Model A) and weight Z-scores (Model B), for each outcome variable. Additional control variables were the child’s age, sex and Tanner stage at eight to 10 years of age
Figure 1).
Relationship between infant growth (slope for body mass index [BMI] Z-score from zero to two years of age) and childhood adiposity (Fat mass index [FMI], kg/m2) according to maternal BMI in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) cohort
DISCUSSION
We examined the relationship among measurements of birth weight, infant growth and parental weight with body composition in a cohort of Caucasian children born at term who were an appropriate weight for their gestational age and had a parental history of obesity. We found positive associations between childhood adiposity and increased birth weight and increased infant growth velocity, and both birth weight and infant growth are independent risk factors for childhood obesity. Moreover, the effect of rapid infant growth on later adiposity was found to be more important with increasing maternal BMI but not with increasing paternal BMI.
Birth weight, childhood adiposity and parental influences
In our cohort, the heaviest children at birth were also the heaviest at eight to 10 years of age based on both anthropometric and body composition measures. Previous studies using DEXA to assess body composition have reported that higher, but appropriate for gestational age, birth weight correlates positively with later lean body mass to a greater extent than with fat mass (3–5), and that the strength of this association increases with age (21). While we also found a positive association between BMI at birth and childhood lean body mass, the magnitude of the association was stronger for fat mass than for lean mass. Our results might be explained by the participants’ inherited genetic load due to a parental history of obesity predisposing them to a greater capacity for accumulating fat mass than lean mass compared with children without a parental history of obesity.
Another study reported positive associations between BMI and weight at birth with both anthropometric and DEXA measures of central adiposity (4). We found positive associations when using anthropometric measures of central adiposity only; exploring this relationship further, we found that waist circumference is, in fact, a function of both trunk lean mass and trunk fat mass.
With respect to the mother’s and father’s BMI measured when the child was between eight and 10 years of age, ours results suggest that they do not influence the associations between the child’s birth weight or BMI and later adiposity. Other studies have demonstrated that maternal prepregnancy weight and gestational weight gain (7) are risk factors for increased child birth weight (22) and adiposity in subsequent years (23). Similarly, paternal weight may be associated with birth weight but to a lesser extent than that of maternal weight (10,11,24,25). However, these studies examined maternal and parental weight as risk factors for child birth weight or later weight, not as moderators in the association between early growth and weight during childhood. We could not assess the influence of earlier measures of parental BMI (eg, at child’s conception or in the first years of life) on the association between early growth and childhood adiposity because these data were not available in the present study.
Infant growth velocity, childhood adiposity and parental influences
In the past 10 years, substantial evidence has emerged suggesting that rapid weight gain during the first years of life, usually measured as age-adjusted weight gain, plays a role in the occurrence of obesity in children independently of birth weight (1,4,22,26). Our findings are consistent with this line of evidence. Recent studies point to even more specific periods when infant growth is most strongly associated with later adiposity, namely in the first three months (3,22) or even in the first week of life (27). Associations between infant growth velocity and childhood body composition were approximately three times stronger for fat mass than for lean mass. Others have found similar results, albeit with a less marked difference between fat mass and lean mass or with similar increases in fat and lean mass (4). Because our sample was restricted to children born at term who were an appropriate size for their gestational age, infancy weight gain was related to genetic background and environmental factors and is not the result of a compensatory mechanism following intrauterine growth retardation.
Our findings further suggest that maternal weight modifies the effect of infancy weight gain on childhood adiposity, while the father’s weight does not. Some studies have considered the influence of parental BMI on infant growth velocity but none have evaluated the impact of this interaction on childhood body composition (10,11,22). Although, in the present study, genetic influences cannot be disentangled from environmental nutritional influences, our findings may be due to the rate of postnatal growth, which is, in part, determined by the quantity and quality of ingested food (28), and mothers typically control food during the first years of life (29). Therefore, maternal BMI combined with rapid growth during infancy may constitute another direct risk factor for childhood obesity, while a similar interaction between paternal BMI and rapid growth during infancy does not appear to exist.
We did not find that the combined effect of birth weight and infant growth velocity was more strongly associated with adiposity at eight to 10 years of age, suggesting that they are independent risk factors and that the presence of both does not put one at greater risk of obesity during childhood. We also did not find that the child’s sex effected the associations examined.
A strength of the present study was the use of DEXA, which is highly precise and provides validated measures of body composition (30). While multiple measures of weight and length in the first two years of life were available, data obtained from ‘Health Booklets’ were not collected for research purposes; therefore, variability in measurement precision is likely. However, all data were examined by two paediatricians and any possibly aberrant measurements were removed (22 measurements). An additional limitation was that parental BMI measures at the time the child was eight to 10 years of age were used as a proxy of parental weight status during the first two years of the child’s life. Although obesity is known to track over time, parental weight status may have changed over this period. Finally, we did not have nutritional data for the infancy period, such as breastfeeding duration and age at introduction of solid foods; as a result, influences of early nutrition on the associations of interest could not be investigated.
CONCLUSION
As was found in other studies, weight and BMI at birth correlated positively with different measures of adiposity at eight to 10 years of age but with a greater proportion of fat mass compared with lean mass than has been reported previously. Infant growth velocity from zero to two years of age also correlated positively with later adiposity, and its effect increased with greater maternal BMI, but not with greater paternal BMI. The present study emphasizes the importance of monitoring weight gain during childhood, particularly among children who had a high birth weight or rapid growth between zero and two years of age and whose mother has a high BMI. Use of early childhood measures of growth and mother’s BMI should be further investigated as part of a comprehensive range of risk indicators for future obesity.
Acknowledgments
The QUALITY Cohort is funded by the Canadian Institutes Health Research (CIHR), the Heart and Stroke Foundation of Canada and the Fonds de la Recherche en Santé du Quebec (FRSQ). LGL is the recipient of a fellowship from the CHU Sainte-Justine. TB is an FRSQ Research Scholar at the Junior 1 level; AVH holds a doctoral scholarship from the FRSQ. JOL holds a Canada Research Chair in the Early Determinants of Adult Chronic Disease. The authors thank the children and parents of the QUALITY cohort and the research assistants (Francisco Caballero, Hugues Charron, Ginette Lagacé, Natacha Marion and Catherine Pelletier). Our infinite gratitude, affection and respect to Dr Marie Lambert.
Footnotes
CONFLICTS OF INTEREST: The authors have no financial disclosures or conflicts of interest to declare.
TABLE S1.
Measures of adiposity at eight to 10 years of age according to varying birth weights, rates of weight gain from zero to two years of age and mother’s body mass index (BMI) among girls in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study
| Measurement at birth | Measurement at two years of age | Measurements at eight to 10 years of age | |||||
|---|---|---|---|---|---|---|---|
|
|
|
|
|||||
| Weight, kg | Sex-specific weight Z-score | Weight, kg | Increase in weight Z-score from zero to two years of age | Mother’s BMI, kg/m2 | Child’s waist circumference, cm | Child’s fat mass index | Child’s BMI Z-score |
| 2.80 | −1 | 10.15 | 0 | 20 | 55.23 | 2.70 | −0.68 |
| 0 | 25 | 57.17 | 3.34 | −0.40 | |||
| 0 | 30 | 59.11 | 3.99 | −0.13 | |||
| 2.80 | −1 | 10.80 | 0.5 | 20 | 55.24 | 2.70 | −0.68 |
| 0.5 | 25 | 57.18 | 3.35 | −0.40 | |||
| 0.5 | 30 | 59.13 | 4.00 | −0.12 | |||
| 2.80 | −1 | 11.50 | 1 | 20 | 55.25 | 2.71 | −0.68 |
| 1 | 25 | 57.19 | 3.36 | −0.40 | |||
| 1 | 30 | 59.14 | 4.01 | −0.12 | |||
| 2.80 | −1 | 12.20 | 1.5 | 20 | 55.26 | 2.72 | −0.68 |
| 1.5 | 25 | 57.21 | 3.36 | −0.40 | |||
| 1.5 | 30 | 59.16 | 4.01 | −0.12 | |||
| 3.25 | 0 | 11.50 | 0 | 20 | 57.96 | 3.33 | −0.29 |
| 0 | 25 | 59.90 | 3.97 | −0.01 | |||
| 0 | 30 | 61.84 | 4.62 | 0.27 | |||
| 3.25 | 0 | 12.20 | 0.5 | 20 | 57.97 | 3.33 | −0.29 |
| 0.5 | 25 | 59.91 | 3.98 | −0.01 | |||
| 0.5 | 30 | 61.86 | 4.63 | 0.27 | |||
| 3.25 | 0 | 13.05 | 1 | 20 | 57.98 | 3.34 | −0.28 |
| 1 | 25 | 59.92 | 3.99 | −0.01 | |||
| 1 | 30 | 61.87 | 4.64 | 0.27 | |||
| 3.25 | 0 | 13.90 | 1.5 | 20 | 57.99 | 3.35 | −0.28 |
| 1.5 | 25 | 59.94 | 3.99 | 0.00 | |||
| 1.5 | 30 | 61.89 | 4.64 | 0.27 | |||
| 3.70 | 1 | 13.05 | 0 | 20 | 60.69 | 3.96 | 0.11 |
| 0 | 25 | 62.63 | 4.60 | 0.39 | |||
| 0 | 30 | 64.57 | 5.25 | 0.67 | |||
| 3.70 | 1 | 13.90 | 0.5 | 20 | 60.70 | 3.96 | 0.11 |
| 0.5 | 25 | 62.64 | 4.61 | 0.39 | |||
| 0.5 | 30 | 64.59 | 5.26 | 0.67 | |||
| 3.70 | 1 | 14.85 | 1 | 20 | 60.71 | 3.97 | 0.11 |
| 1 | 25 | 62.65 | 4.62 | 0.39 | |||
| 1 | 30 | 64.60 | 5.27 | 0.67 | |||
| 3.70 | 1 | 15.90 | 1.5 | 20 | 60.72 | 3.98 | 0.11 |
| 1.5 | 25 | 62.67 | 4.62 | 0.39 | |||
| 1.5 | 30 | 64.62 | 5.27 | 0.67 | |||
For each weight-at-birth Z-score (−1, 0 or +1) (measurement at birth), the weight a female child would be at two years of age if she increased her weight by 0, 0.5, 1 or 1.5 SDs (measurement at age two years of age) was estimated. Similarly, for each of these cases, the effect on waist circumference, fat mass index and BMI Z-score at eight to 10 years of age according to different maternal BMI values (20 kg/m2, 25 kg/m2 or 30 kg/m2) (measurements at eight to 10 years of age) was estimated. For example, a girl born with a BMI Z-score of −1 SDs (2.8 kg) that had an increase in weight Z-score from zero to two years of age of 1.5 SDs and her mother had a BMI of 30 kg/m2, when she was eight to 10 years of age, will have a waist circumference of 59.16 cm, whereas her waist circumference would have been 55.26 cm if her mother’s BMI was 20 kg/m2
TABLE S2.
Measures of adiposity at eight to 10 years of age according to varying birth weights, rates of weight gain from zero to two years of age, and mother’s body mass index (BMI) among boys in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study
| Measurement at birth | Measurement at two years of age | Measurements at eight to 10 years of age | |||||
|---|---|---|---|---|---|---|---|
|
|
|
|
|||||
| Weight, kg | Sex-specific Weight Z-score | Weight, kg | Increase in weight Z-score from zero to two years of age | Mother’s BMI, kg/m2 | Child’s waist circumference, cm | Child’s fat mass index | Child’s BMI Z-score |
| 2.85 | −1 | 10.85 | 0 | 20 | 56.80 | 2.14 | −0.36 |
| 0 | 25 | 58.74 | 2.79 | −0.08 | |||
| 0 | 30 | 60.68 | 3.44 | 0.19 | |||
| 2.85 | −1 | 11.45 | 0.5 | 20 | 56.81 | 2.15 | −0.36 |
| 0.5 | 25 | 58.75 | 2.80 | −0.08 | |||
| 0.5 | 30 | 60.70 | 3.45 | 0.19 | |||
| 2.85 | −1 | 12.15 | 1 | 20 | 56.82 | 2.16 | −0.36 |
| 1 | 25 | 58.76 | 2.80 | −0.08 | |||
| 1 | 30 | 60.71 | 3.45 | 0.20 | |||
| 2.85 | −1 | 12.85 | 1.5 | 20 | 56.83 | 2.16 | −0.36 |
| 1.5 | 25 | 58.78 | 2.81 | −0.08 | |||
| 1.5 | 30 | 60.73 | 3.46 | 0.20 | |||
| 3.35 | 0 | 12.15 | 0 | 20 | 59.53 | 2.77 | 0.03 |
| 0 | 25 | 61.47 | 3.42 | 0.31 | |||
| 0 | 30 | 63.41 | 4.07 | 0.59 | |||
| 3.35 | 0 | 12.85 | 0.5 | 20 | 59.54 | 2.78 | 0.03 |
| 0.5 | 25 | 61.48 | 3.43 | 0.31 | |||
| 0.5 | 30 | 63.43 | 4.08 | 0.59 | |||
| 3.35 | 0 | 13.65 | 1 | 20 | 59.55 | 2.79 | 0.04 |
| 1 | 25 | 61.49 | 3.43 | 0.31 | |||
| 1 | 30 | 63.44 | 4.08 | 0.59 | |||
| 3.35 | 0 | 14.45 | 1.5 | 20 | 59.56 | 2.79 | 0.04 |
| 1.5 | 25 | 61.51 | 3.44 | 0.32 | |||
| 1.5 | 30 | 63.46 | 4.09 | 0.59 | |||
| 3.85 | 1 | 13.65 | 0 | 20 | 62.26 | 3.40 | 0.43 |
| 0 | 25 | 64.20 | 4.05 | 0.71 | |||
| 0 | 30 | 66.14 | 4.70 | 0.98 | |||
| 3.85 | 1 | 14.45 | 0.5 | 20 | 62.27 | 3.41 | 0.43 |
| 0.5 | 25 | 64.21 | 4.06 | 0.71 | |||
| 0.5 | 30 | 66.16 | 4.71 | 0.99 | |||
| 3.85 | 1 | 15.30 | 1 | 20 | 62.28 | 3.42 | 0.43 |
| 1 | 25 | 64.22 | 4.06 | 0.71 | |||
| 1 | 30 | 66.17 | 4.71 | 0.99 | |||
| 3.85 | 1 | 16.20 | 1.5 | 20 | 62.29 | 3.42 | 0.43 |
| 1.5 | 25 | 64.24 | 4.07 | 0.71 | |||
| 1.5 | 30 | 66.19 | 4.72 | 0.99 | |||
For each weight-at-birth Z-score (−1, 0 or +1) (measurement at birth), the weight a male child would be at two years of age if he increased his weight by 0, 0.5, 1 or 1.5 SDs (measurement at two years of age) was estimated. Similarly, for each of these cases, the effect on waist circumference, fat mass index and BMI Z-score at eight to 10 years of age according to different maternal BMI values (20 kg/m2, 25 kg/m2 or 30 kg/m2) (measurements at eight to 10 years of age) was estimated. For example, a boy born with a BMI Z-score of −1 SDs (2.8 kg) that had an increase in weight Z-score from zero to two years of age of 1.5 SDs and his mother had a BMI of 30 kg/m2, when he was eight to 10 years of age will, have a waist circumference of 60.73 cm, whereas his waist circumference would have been 56.83 cm if his mother’s BMI was 20 kg/m2
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
TABLE S1.
Measures of adiposity at eight to 10 years of age according to varying birth weights, rates of weight gain from zero to two years of age and mother’s body mass index (BMI) among girls in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study
| Measurement at birth | Measurement at two years of age | Measurements at eight to 10 years of age | |||||
|---|---|---|---|---|---|---|---|
|
|
|
|
|||||
| Weight, kg | Sex-specific weight Z-score | Weight, kg | Increase in weight Z-score from zero to two years of age | Mother’s BMI, kg/m2 | Child’s waist circumference, cm | Child’s fat mass index | Child’s BMI Z-score |
| 2.80 | −1 | 10.15 | 0 | 20 | 55.23 | 2.70 | −0.68 |
| 0 | 25 | 57.17 | 3.34 | −0.40 | |||
| 0 | 30 | 59.11 | 3.99 | −0.13 | |||
| 2.80 | −1 | 10.80 | 0.5 | 20 | 55.24 | 2.70 | −0.68 |
| 0.5 | 25 | 57.18 | 3.35 | −0.40 | |||
| 0.5 | 30 | 59.13 | 4.00 | −0.12 | |||
| 2.80 | −1 | 11.50 | 1 | 20 | 55.25 | 2.71 | −0.68 |
| 1 | 25 | 57.19 | 3.36 | −0.40 | |||
| 1 | 30 | 59.14 | 4.01 | −0.12 | |||
| 2.80 | −1 | 12.20 | 1.5 | 20 | 55.26 | 2.72 | −0.68 |
| 1.5 | 25 | 57.21 | 3.36 | −0.40 | |||
| 1.5 | 30 | 59.16 | 4.01 | −0.12 | |||
| 3.25 | 0 | 11.50 | 0 | 20 | 57.96 | 3.33 | −0.29 |
| 0 | 25 | 59.90 | 3.97 | −0.01 | |||
| 0 | 30 | 61.84 | 4.62 | 0.27 | |||
| 3.25 | 0 | 12.20 | 0.5 | 20 | 57.97 | 3.33 | −0.29 |
| 0.5 | 25 | 59.91 | 3.98 | −0.01 | |||
| 0.5 | 30 | 61.86 | 4.63 | 0.27 | |||
| 3.25 | 0 | 13.05 | 1 | 20 | 57.98 | 3.34 | −0.28 |
| 1 | 25 | 59.92 | 3.99 | −0.01 | |||
| 1 | 30 | 61.87 | 4.64 | 0.27 | |||
| 3.25 | 0 | 13.90 | 1.5 | 20 | 57.99 | 3.35 | −0.28 |
| 1.5 | 25 | 59.94 | 3.99 | 0.00 | |||
| 1.5 | 30 | 61.89 | 4.64 | 0.27 | |||
| 3.70 | 1 | 13.05 | 0 | 20 | 60.69 | 3.96 | 0.11 |
| 0 | 25 | 62.63 | 4.60 | 0.39 | |||
| 0 | 30 | 64.57 | 5.25 | 0.67 | |||
| 3.70 | 1 | 13.90 | 0.5 | 20 | 60.70 | 3.96 | 0.11 |
| 0.5 | 25 | 62.64 | 4.61 | 0.39 | |||
| 0.5 | 30 | 64.59 | 5.26 | 0.67 | |||
| 3.70 | 1 | 14.85 | 1 | 20 | 60.71 | 3.97 | 0.11 |
| 1 | 25 | 62.65 | 4.62 | 0.39 | |||
| 1 | 30 | 64.60 | 5.27 | 0.67 | |||
| 3.70 | 1 | 15.90 | 1.5 | 20 | 60.72 | 3.98 | 0.11 |
| 1.5 | 25 | 62.67 | 4.62 | 0.39 | |||
| 1.5 | 30 | 64.62 | 5.27 | 0.67 | |||
For each weight-at-birth Z-score (−1, 0 or +1) (measurement at birth), the weight a female child would be at two years of age if she increased her weight by 0, 0.5, 1 or 1.5 SDs (measurement at age two years of age) was estimated. Similarly, for each of these cases, the effect on waist circumference, fat mass index and BMI Z-score at eight to 10 years of age according to different maternal BMI values (20 kg/m2, 25 kg/m2 or 30 kg/m2) (measurements at eight to 10 years of age) was estimated. For example, a girl born with a BMI Z-score of −1 SDs (2.8 kg) that had an increase in weight Z-score from zero to two years of age of 1.5 SDs and her mother had a BMI of 30 kg/m2, when she was eight to 10 years of age, will have a waist circumference of 59.16 cm, whereas her waist circumference would have been 55.26 cm if her mother’s BMI was 20 kg/m2
TABLE S2.
Measures of adiposity at eight to 10 years of age according to varying birth weights, rates of weight gain from zero to two years of age, and mother’s body mass index (BMI) among boys in the Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) study
| Measurement at birth | Measurement at two years of age | Measurements at eight to 10 years of age | |||||
|---|---|---|---|---|---|---|---|
|
|
|
|
|||||
| Weight, kg | Sex-specific Weight Z-score | Weight, kg | Increase in weight Z-score from zero to two years of age | Mother’s BMI, kg/m2 | Child’s waist circumference, cm | Child’s fat mass index | Child’s BMI Z-score |
| 2.85 | −1 | 10.85 | 0 | 20 | 56.80 | 2.14 | −0.36 |
| 0 | 25 | 58.74 | 2.79 | −0.08 | |||
| 0 | 30 | 60.68 | 3.44 | 0.19 | |||
| 2.85 | −1 | 11.45 | 0.5 | 20 | 56.81 | 2.15 | −0.36 |
| 0.5 | 25 | 58.75 | 2.80 | −0.08 | |||
| 0.5 | 30 | 60.70 | 3.45 | 0.19 | |||
| 2.85 | −1 | 12.15 | 1 | 20 | 56.82 | 2.16 | −0.36 |
| 1 | 25 | 58.76 | 2.80 | −0.08 | |||
| 1 | 30 | 60.71 | 3.45 | 0.20 | |||
| 2.85 | −1 | 12.85 | 1.5 | 20 | 56.83 | 2.16 | −0.36 |
| 1.5 | 25 | 58.78 | 2.81 | −0.08 | |||
| 1.5 | 30 | 60.73 | 3.46 | 0.20 | |||
| 3.35 | 0 | 12.15 | 0 | 20 | 59.53 | 2.77 | 0.03 |
| 0 | 25 | 61.47 | 3.42 | 0.31 | |||
| 0 | 30 | 63.41 | 4.07 | 0.59 | |||
| 3.35 | 0 | 12.85 | 0.5 | 20 | 59.54 | 2.78 | 0.03 |
| 0.5 | 25 | 61.48 | 3.43 | 0.31 | |||
| 0.5 | 30 | 63.43 | 4.08 | 0.59 | |||
| 3.35 | 0 | 13.65 | 1 | 20 | 59.55 | 2.79 | 0.04 |
| 1 | 25 | 61.49 | 3.43 | 0.31 | |||
| 1 | 30 | 63.44 | 4.08 | 0.59 | |||
| 3.35 | 0 | 14.45 | 1.5 | 20 | 59.56 | 2.79 | 0.04 |
| 1.5 | 25 | 61.51 | 3.44 | 0.32 | |||
| 1.5 | 30 | 63.46 | 4.09 | 0.59 | |||
| 3.85 | 1 | 13.65 | 0 | 20 | 62.26 | 3.40 | 0.43 |
| 0 | 25 | 64.20 | 4.05 | 0.71 | |||
| 0 | 30 | 66.14 | 4.70 | 0.98 | |||
| 3.85 | 1 | 14.45 | 0.5 | 20 | 62.27 | 3.41 | 0.43 |
| 0.5 | 25 | 64.21 | 4.06 | 0.71 | |||
| 0.5 | 30 | 66.16 | 4.71 | 0.99 | |||
| 3.85 | 1 | 15.30 | 1 | 20 | 62.28 | 3.42 | 0.43 |
| 1 | 25 | 64.22 | 4.06 | 0.71 | |||
| 1 | 30 | 66.17 | 4.71 | 0.99 | |||
| 3.85 | 1 | 16.20 | 1.5 | 20 | 62.29 | 3.42 | 0.43 |
| 1.5 | 25 | 64.24 | 4.07 | 0.71 | |||
| 1.5 | 30 | 66.19 | 4.72 | 0.99 | |||
For each weight-at-birth Z-score (−1, 0 or +1) (measurement at birth), the weight a male child would be at two years of age if he increased his weight by 0, 0.5, 1 or 1.5 SDs (measurement at two years of age) was estimated. Similarly, for each of these cases, the effect on waist circumference, fat mass index and BMI Z-score at eight to 10 years of age according to different maternal BMI values (20 kg/m2, 25 kg/m2 or 30 kg/m2) (measurements at eight to 10 years of age) was estimated. For example, a boy born with a BMI Z-score of −1 SDs (2.8 kg) that had an increase in weight Z-score from zero to two years of age of 1.5 SDs and his mother had a BMI of 30 kg/m2, when he was eight to 10 years of age will, have a waist circumference of 60.73 cm, whereas his waist circumference would have been 56.83 cm if his mother’s BMI was 20 kg/m2