Disadvantage and disordered eating in boys: Examining phenotypic and genotype × environment associations across development.

Abstract

Socioeconomic disadvantage may be a significant risk factor for disordered eating, particularly for individuals with underlying genetic risk. However, little to nothing is known about the impact of disadvantage on disordered eating in boys during the critical developmental risk period. Crucially, risk models developed for girls may not necessarily apply to boys, as boys show different developmental patterns of disordered eating risk (i.e., earlier activation of genetic influences during adrenarche, an early stage of puberty). This is the first study to examine phenotypic and Genotype 3 Environment (G 3 E) effects of disadvantage in boys. Analyses examined 3,484 male twins ages 8-17 (M age = 12.27, SD = 2.96) from the Michigan State University Twin Registry. Disordered eating (e.g., body dissatisfaction, binge eating) was measured using the parent-report Michigan Twins Project Eating Disorder Survey. Neighborhood disadvantage was measured using a census-tract level Area Deprivation Index, and family socioeconomic status was determined from parental income and education. Adrenarche status was determined using multiple indicators, including age and Pubertal Development Scale scores. G 3 E models suggested that genetic influences on disordered eating were activated earlier for boys experiencing familial or neighborhood disadvantage, with substantial genetic influences in early adrenarche, when genetic influences were low in more advantaged boys. Phenotypically, both neighborhood and familial disadvantage were associated with greater disordered eating for boys in late adrenarche, which could indicate a lasting impact of earlier activation of genetic influences on later risk. Results highlight disadvantage as a novel risk factor for disordered eating in boys, particularly those with genetic vulnerabilities.

Associations between household income and disordered eating differ across sex and racial identity in a population‐based sample of adults

“…The MTP‐ED was previously validated in male and female youth and shown to have strong correlations with other disordered eating measures (Mikhail et al, 2021, 2023). Internal consistency was excellent for both women ( α = .86) and men ( α = .83) in the current sample, as well as in Black participants ( α = .82), White participants ( α = .86), and participants with another racial/ethnic identity ( α = .87).…”

“…However, some more contemporary studies suggest people experiencing socioeconomic disadvantage may have equal or greater rates of EDs and disordered eating behaviors than their more advantaged peers (Gard & Freeman, 1996; Mitchison et al, 2014; Reagan & Hersch, 2005). Results in youth have been particularly consistent in showing increased rates of disordered eating among both boys and girls experiencing familial or neighborhood disadvantage in population‐based samples (Carroll et al, 2023; Mikhail et al, 2021, 2023). These findings align with research showing that socioeconomic disadvantage is associated with other negative mental health outcomes closely related to EDs, including anxiety and depression (Mwinyi et al, 2017; Ross, 2000).…”

“…Because height and weight were self-reported, the initial data contained some extreme values that likely reflected errors in reporting (raw BMI range = 2.79-138.66). Consistent with our prior studies of disadvantage in youth (Mikhail et al, 2021(Mikhail et al, , 2023, we used an empirical approach for removing outliers by setting BMI values above the 99.5th percentile or below the 0.5th percentile in the current sample to missing.…”

“…Given limited prior research, our analyses were somewhat exploratory. However, following prior population-based studies in youth (Carroll et al, 2023;Mikhail et al, 2021Mikhail et al, , 2023, we expected to find that lower SES was associated with greater ED symptoms for both women and men during at least some life stages. Based on prior work by Burke et al (2022) in college students, we expected to find similar or stronger associations between lower SES and increased disordered eating in Black participants relative to White participants due to the added psychological burden and enhanced financial stress (e.g., denied employment or housing opportunities) that may result from racial prejudice and discrimination.…”

Shared genetic influences between eating disorders and gastrointestinal disease in a large, population-based sample of adult women and men

“…It has strong correlations with other ED measures (e.g. Eating Disorder Examination Questionnaire; Fairburn and Beglin, 1994) and significant associations with anxiety/depressive symptoms (Mikhail et al, 2021(Mikhail et al, , 2023 and (inversely) wellbeing (Mikhail et al, in press). Internal consistency in the current sample is excellent for both women (α = 0.86) and men (α = 0.83).…”