Association of maternal pre-pregnancy BMI and breastfeeding with NAFLD in young adults: a parental negative control study

Background: The importance of the maternal-infant dyad in the genesis of nonalcoholic fatty liver disease (NAFLD) is of increasing interest. The Avon Longitudinal Study of Parents and Children (ALSPAC) showed that at age 24, 1 in 5 had NAFLD measured by transient elastography and controlled attenuation parameter (CAP). Our aim was to investigate the association between breastfeeding duration and maternal pre-pregnancy BMI on offspring NAFLD in young adulthood. Methods: 4021 participants attended clinic for FibroScan and CAP measurement using Echosens 502 Touch (R). 440 participants with Alcohol Use Disorders were excluded. Offspring of 100 non-singleton pregnancies were excluded. 2961 valid CAP measurements for NAFLD were analysed. Exposures of interest were breast-feeding of any duration, >= 6months exclusive breastfeeding, and maternal pre-pregnancy BMI. Multivariable regression models estimated the odds of NAFLD at 24 years. We performed a paternal negative control test to explore residual confounding in the analyses of pre-pregnancy BMI. Findings: There was a modest inverse association of exclusive and non-exclusive breastfeeding >= 6 months having a protective effect on NAFLD in offspring (OR 0.92 [95%CI 0.66-1.27] and OR 0.90 [0.67-1.21] respectively). The odds of offspring NAFLD in overweight pre-pregnancy maternal BMI and paternal BMI was OR 2.09 [1.62-2.68] and OR 1.33 [95%CI 1.07-1.65] respectively, with the ratio of effect sizes OR 1.57 [1.11-2.22]. Similarly, odds of offspring NAFLD with obese pre-pregnancy maternal BMI and paternal BMI was OR 2.66 [1.71-4.14] and OR 135 [0.91-2.00] respectively, with the ratio of effect sizes OR 1 .98 [1.05-3.74]. Interpretation: Higher maternal pre-pregnancy BMI was associated with offspring NAFLD, having accounted for shared parental confounding. We did not replicate previous work that found a strong association between breastfeeding and NAFLD. Crown Copyright (C) 2021 Published by Elsevier Ltd.

Automated summary

The study found that higher maternal pre-pregnancy BMI may increase the risk of offspring developing NAFLD, but did not replicate previous findings of a strong association between breastfeeding and NAFLD.