Increased body mass index in parent-child dyads predicts the offspring risk of meeting bariatric surgery criteria

Context: Obesity in children is a major public health concern.

Objective: This study examined the value of using parent-child dyads' adiposity status for predicting the individual's later eligibility for bariatric surgery (EBS).

Design, Setting, and Participants: The cohort consisted of 2647 individuals from the longitudinal Cardiovascular Risk in Young Finns Study. Baseline information included own and parental body mass index (BMI) in 1980 (children aged 3-18 years), whereas adult follow-up assessment examined EBS 21-31 years later.

Main Outcome Measure: EBS in adulthood was defined as: 1) BMI greater than 40 kg/m² or 2) BMI greater than 35 kg/m² with at least one of the following metabolic complications: type 2 diabetes, hypertension, or dyslipidemia.

Results: Addition of parents' BMI improved the prediction of adulthood EBS compared to the model including child's BMI, age, and sex (area under the curve values [95% confidence interval] (0.80 [0.74–0.85] vs 0.74 [0.68–0.81], P = .003). Obese children with an obese parent had a 21.2% chance of being EBS in adulthood. Compared to nonobese families, the risk ratio for EBS was 14.2 (95% confidence interval 8.0–25.2, P < .001) in obese children with an obese parent. The absolute risk of EBS was 30.9% if both child and parent were obese on more than one childhood assessment compared to 15.2% if they were obese only once, or 2.1% if they were never obese (P < .05).

Conclusions: These longitudinal data show that a combination of the child's and parents' BMI at baseline assessment is a useful predictive tool for assessing later EBS, and highlights the importance of accounting for parental BMI in the assessment of child obesity.