Unmet Social Needs and Patterns of Hair Cortisol Concentration in Mother-Child Dyads.

Background: Mothers and their children demonstrate dyadic synchrony of hypothalamic-pituitary-adrenal (HPA) axis function, likely influenced by shared genetic or environmental factors. Although evidence has shown that chronic stress exposure has physiologic consequences for individuals-including on the HPA axis-minimal research has explored how unmet social needs such as food and housing instability may be associated with chronic stress and HPA axis synchrony in mother-child dyads.

Methods: We conducted a secondary analysis of data from 364 mother-child dyads with low-income recruited during a randomized trial conducted in an urban pediatric clinic. We used latent profile analysis (LPA) to identify subgroups based on naturally occurring patterns of within-dyad hair cortisol concentration (HCC). A logistic regression model predicted dyadic HCC profile membership as a function of summative count of survey-reported unmet social needs, controlling for demographic and health covariates.

Results: LPA of HCC data from dyads revealed a 2-profile model as the best fit. Comparisons of log HCC for mothers and children in each profile group resulted in significantly "higher dyadic HCC" versus "lower dyadic HCC" profiles (median log HCC for mothers: 4.64 vs 1.58; children: 5.92 vs 2.79, respectively;  < .001). In the fully adjusted model, each one-unit increase in number of unmet social needs predicted significantly higher odds of membership in the higher dyadic HCC profile when compared to the lower dyadic HCC profile (odds ratio  =  1.13; 95% confidence interval [1.04-1.23];   =  .01).

Conclusion: Mother-child dyads experience synchronous patterns of physiologic stress, and an increasing number of unmet social needs is associated with a profile of higher dyadic HCC. Interventions aimed at decreasing family-level unmet social needs or maternal stress are, therefore, likely to affect pediatric stress and related health inequities; efforts to address pediatric stress similarly may affect maternal stress and related health inequities. Future research should explore the measures and methods needed to understand the impact of unmet social needs and stress on family dyads.