Parent-child resemblance in weight status and its correlates in the United States

Abstract

Background: Few studies have examined parent-child resemblance in body weight status using nationally representative data for the US.

Design: We analyzed Body Mass Index (BMI), weight status, and related correlates for 4,846 boys, 4,725 girls, and their parents based on US nationally representative data from the 2006 and 2007 Medical Expenditure Panel Survey (MEPS). Pearson partial correlation coefficients, percent agreement, weighted kappa coefficients, and binary and multinomial logistic regression were used to examine parent-child resemblance, adjusted for complex sampling design.

Results: Pearson partial correlation coefficients between parent and child's BMI measures were 0.15 for father-son pairs, 0.17 for father-daughter pairs, 0.20 for mother-son pairs, and 0.23 for mother-daughter pairs. The weighted kappa coefficients between BMI quintiles of parent and child ranged from -0.02 to 0.25. Odds ratio analyses found children were 2.1 (95% confidence interval (CI): 1.6, 2.8) times more likely to be obese if only their father was obese, 1.9 (95% CI: 1.5, 2.4) times more likely if only their mother was obese, and 3.2 (95% CI: 2.5, 4.2) times more likely if both parents were obese.

Conclusions: Parent-child resemblance in BMI appears weak and may vary across parent-child dyad types in the US population. However, parental obesity status is associated with children's obesity status. Use of different measures of parent-child resemblance in body weight status can lead to different conclusions.

Figure 1. Age trends in the Pearson partial correlation coefficient between parent’s BMI and child’s BMI for age by dyad types.

X axis: Kid’ age. Y axis: Correlation coefficient r. P value for dyads: P  = 0.0008 for mother-daughter pairs; P  = 0.9784 for mother-son pairs; P  = 0.3101 for father-daughter pairs; P  = 0.4100 for father- son pairs.