Dads With Obesity Mostly Cleared in Their Children’s NAFLD

Obesity prior to pregnancy in women was significantly associated with nonalcoholic fatty liver disease (NAFLD) in their children by young adulthood, a researcher said.

Compared with women who did not have obesity (body mass index [BMI] less than 30) before pregnancy, a pre-pregnancy maternal BMI of 30 or greater was strongly associated with NAFLD in their children by age 24 (adjusted OR 2.62, 95% CI 1.71-4.14, P<0.0001), while the association between paternal BMI in obese men and NAFLD was non-significant (adjusted OR 1.35, 95% CI 0.91-2.00, P=0.14), reported Kushala Abeysekera, MBBS, of the University of Bristol in England.

After adjustment, the relationship between maternal BMI of women with overweight and NAFLD in offspring remained strong (adjusted OR 2.09, 95% CI 1.62-2.68, P<0.0001), while the relationship between paternal BMI and NAFLD was attenuated (adjusted OR 1.33, 95% CI 1.07-1.65, P=0.01).

With a high calorie diet, some individuals can go on to develop liver steatosis and, ultimately, fibrosis, Abeysekera noted during a presentation at the European Association for the Study of the Liver virtual meeting.

“But it got us all thinking: are all the epidemiological studies reporting on environmental confounding?” he said. “Is there actually a causal association with obesity and offspring going on to develop NAFLD?”

Abeysekera’s group investigated this using a paternal negative control test design to examine the link between pre-pregnancy maternal BMI and NAFLD in offspring in young adulthood. They examined data from the Avon Longitudinal Study of Parents and Children cohort in the southwestern U.K., where children have been followed for the last 3 decades.

Current adults were assessed for NAFLD at two time points: at age 17 using ultrasound, and via a more detailed FibroScan at age 24. Participants also provided blood samples to assess liver function and completed lifestyle questionnaires to obtain their history of alcohol use.

At the ultrasound at age 17, one in five participants had NAFLD, as defined by a controlled attenuation parameter (CAP) score and a steatosis grade of S1 or higher, the authors noted.

Overall, 2,961 valid CAP scores were analyzed for participants at age 24. Maternal pre-pregnancy BMI and paternal BMI were adjusted for confounders, including maternal age, smoking during pregnancy, and socioeconomic status.

Of young adults with NAFLD, 41% had mothers with pre-pregnancy obesity, while 30% had mothers with pre-pregnancy overweight. In contrast, 29% of young adults with NAFLD had fathers with obesity, and 23% had fathers with overweight.

Abeysekera noted that this was a cohort of asymptomatic 24-year-olds, and that the study reported on steatosis, not fibrosis. Interestingly, the researchers did not find an association between fibrosis and maternal BMI.

This study supports an “early life effect,” since despite accounting for shared parental confounding, the relationship persisted, reflecting the “obesogenic environment” that patients live in, said Abeysekera.