Is economic hardship associated with young children's cortisol levels?

Economic hardship during childhood has been linked to poor physical and mental health. This study examines cross‐sectional and longitudinal associations of a summed economic hardship score of poverty, food insecurity, and financial hardship with hair cortisol in young children. Data from 24‐month (Time 1, mean age 5 years) and 36‐month (Time 2, mean age 6 years) follow‐up from the NET‐Works obesity prevention trial (NET‐Works, NCT0166891) were used. Hair cortisol measures obtained at each time point were log‐transformed and regressed on economic hardship at Time 1 and a cumulative economic hardship from Time 1 to Time 2, using generalized linear regressions. All models were adjusted for child age, sex, race/ethnicity, and intervention (prevention vs. control) arm. The final analytic sample sizes ranged from 248 to 287. Longitudinal analyses indicated that for every 1‐unit higher economic hardship score at Time 1, hair cortisol at Time 2 follow‐up was on average 0.07 log‐picograms per milligram (pg/mg) higher (95% confidence interval [CI]: 0.01, 0.13). For every 1‐unit increase in the cumulative economic hardship score between Time 1 and 2, there was a 0.04 log‐pg/mg (95% CI: 0.00, 0.07) average higher level of hair cortisol at Time 2 follow‐up. Results show suggestive but limited evidence for an association between economic hardship and cortisol in young children.