Genetic Obesity Disorders: Body Mass Index Trajectories and Age of Onset of Obesity Compared with Children with Obesity from the General Population.

OBJECTIVE: We sought to assess body mass index trajectories of children with genetic obesity to identify optimal early age of onset of obesity (AoO) cut-offs for genetic screening. STUDY DESIGN: This longitudinal, observational study included growth measurements from birth onward of children with nonsyndromic and syndromic genetic obesity and control children with obesity from a population-based cohort. Diagnostic performance of AoO was evaluated. RESULTS: We describe the body mass index trajectories of 62 children with genetic obesity (29 nonsyndromic, 33 syndromic) and 298 controls. Median AoO was 1.2 years in nonsyndromic genetic obesity (0.4 and 0.6 years in biallelic LEPR and MC4R; 1.7 in heterozygous MC4R); 2.0 years in syndromic genetic obesity (0.9, 2.3, 4.3, and 6.8 years in pseudohypoparathyroidism, Bardet-Biedl syndrome, 16p11.2del syndrome, and Temple syndrome, respectively); and 3.8 years in controls. The optimal AoO cut-off was ≤3.9 years (sensitivity, 0.83; specificity, 0.49; area under the curve, 0.79; P < .001) for nonsyndromic and ≤4.7 years (sensitivity, 0.82; specificity, 0.37; area under the curve, 0.68; P = .001) for syndromic genetic obesity. CONCLUSIONS: Optimal AoO cut-off as single parameter to determine which children should undergo genetic testing was ≤3.9 years. In case of older AoO, additional features indicative of genetic obesity should be present to warrant genetic testing. Optimal cut-offs might differ across different races and ethnicities.

Ethnic disparities in maternal obesity and weight gain during pregnancy. The Generation R Study.

OBJECTIVE: To examine ethnic disparities in maternal prepregnancy obesity and gestational weight gain, and to examine to which extent these differences can be explained by socio-demographic, lifestyle and pregnancy related characteristics. METHODS: In a multi-ethnic population-based prospective cohort study among 6444 pregnant women in Rotterdam, the Netherlands, maternal anthropometrics were repeatedly measured throughout pregnancy. Ethnicity, socio-demographic, lifestyle and pregnancy related characteristics were assessed by physical examinations and questionnaires. RESULTS: The prevalence of prepregnancy overweight and obesity was 23.1% among Dutch-origin women. Statistically higher prevalences were observed among Dutch Antillean-origin (40.8%), Moroccan-origin (49.9%), Surinamese-Creole-origin (38.6%) and Turkish-origin (41.1%) women (all p-values <0.05). Only Dutch Antillean-origin, Moroccan-origin, Surinamese-Creole-origin and Turkish-origin women had higher risks of maternal prepregnancy overweight and obesity as compared to Dutch-origin women (p-values <0.05). Socio-demographic and lifestyle related characteristics explained up to 45% of the ethnic differences in body mass index. Compared to Dutch-origin women, total gestational weight gain was lower in all ethnic minority groups, except for Cape Verdean-origin and Surinamese-Creole-origin women (p-values <0.05). Lifestyle and pregnancy related characteristics explained up to 33% and 40% of these associations, respectively. The largest ethnic differences in gestational weight gain were observed in late pregnancy. CONCLUSION: We observed moderate ethnic differences in maternal prepregnancy overweight, obesity and gestational weight gain. Socio-demographic, lifestyle and pregnancy related characteristics partly explained these differences. Whether these differences also lead to ethnic differences in maternal and childhood outcomes should be further studied.

Early origins of ethnic disparities in cardiovascular risk factors.

BACKGROUND: Not much is known about the ethnic differences in cardiovascular risk factors during childhood in European countries. We examined the ethnic differences in childhood cardiovascular risk factors in the Netherlands. METHODS: In a multi-ethnic population-based prospective cohort study, we measured blood pressure, left ventricular mass, and levels of cholesterol, triglyceride and insulin at the median age of 6.2years. RESULTS: As compared to Dutch children, Cape Verdean and Turkish children had a higher blood pressure, whereas Cape Verdean, Surinamese-Creole and Turkish children had higher total-cholesterol levels (p-values<0.05). Turkish children had higher triglyceride levels, but lower insulin levels than Dutch children (p-values<0.05). As compared to Dutch children, only Turkish children had an increased risk of clustering of cardiovascular risk factors (odds ratio: 2.45 (95% confidence interval 1.18, 3.37)). Parental pre-pregnancy factors explained up to 50% of the ethnic differences in childhood risk factors. In addition to these factors, pregnancy and childhood factors and childhood BMI explained up to 50%, 12.5% and 61.1%, respectively. CONCLUSIONS: Our results suggest that compared to Dutch children, Cape Verdean, Surinamese-Creole and Turkish children have an adverse cardiovascular profile. These differences are largely explained by parental pre-pregnancy factors, pregnancy factors and childhood BMI.