Unaffected siblings of adolescents and adults with fragile X syndrome: Effects on maternal well-being

Sibling Support and Perceived Daily Hassles in Latino and Non-Latino Families of Children with DD

Parents of children with developmental delay (DD) report significantly higher levels of parenting stress compared to parents of children with typical development. There is a heightened need for social support among families of children with DD. Siblings play an important role in these contexts as a supportive resource and primary stress buffer. Little to no research has examined how these stress and supportive processes may differ among Latino and non-Latino parents. The current study examined the relation between sibling support and parents' perceived daily hassles between Latino and non-Latino parents of children with DD (N = 146; 65% Latino; mean parent age = 37.39 years; mean child age = 49.63 months; SD = 7.9). Latinos reported significantly greater use of sibling support and lower perceived daily hassles compared to non-Latino counterparts. In the combined sample, greater sibling support was significantly correlated with lower daily hassles. When examined separately in Latino and non-Latino groups, this correlation only remained significant among Latinos. The interaction between ethnicity and sibling support on perceived daily hassles was approaching significance, such that Latinos who reported high levels of sibling support reported lower perceived daily hassles. Findings emphasize the universal importance of familial support systems for the well-being of parents of children with DD and point to the possible protective role of Latino cultural factors that influence the degree to which these supports are employed. Results may inform culturally sensitive adaptations to parenting interventions for Latino families that harness sibling support to target and buffer parenting stress.

Stress and genetics influence hair cortisol in FMR1 premutation carrier mothers of children with fragile X syndrome

To investigate genetic and environmental influences on cortisol levels, mothers of children with fragile X syndrome (FXS) were studied four times over a 7.5-year period. All participants (n = 84) were carriers of the FMR1 "premutation", a genetic condition associated with impaired HPA axis functioning. Genetic variation was indicated by expansions in the number of CGG (cytosine-guanine-guanine) repeats in the FMR1 gene (67-138 repeats in the present sample). The environmental factor was cumulative exposure to adverse life events during the study period. Cortisol was measured at the beginning of the study via saliva samples and at the end of the study via hair samples; hormone values from these two specimen types were significantly correlated. The interactions between CGG repeat number and adverse life events significantly predicted hair cortisol concentration, including after accounting for the initial salivary cortisol level. For those with fewer CGG repeats, stress exposure was associated with elevated cortisol, the expected response to stress, although women with a higher number of CGGs had a reduced cortisol response to adverse events, which might be related to HPA dysfunction. These results indicate that both exogenous and endogenous factors affect HPA functioning in this population of women.

Trajectories of Change in the Behavioral and Health Phenotype of Adolescents and Adults with Fragile X Syndrome and Intellectual Disability: Longitudinal Trends Over a Decade

This study examined trajectories of daily living skills, behavior problems, body mass index (BMI), and health conditions spanning nearly a decade in adolescents and adults with fragile X syndrome (N = 134; age range at study end = 19-49 years), examining influences of sex and autism spectrum disorder (ASD) symptoms. Hierarchical linear modeling revealed early increases in daily living skills, with decreases at older ages. Behavior problems became less severe over time, with some increases at older ages. Individuals gained weight and had increasing health problems over time. Fewer ASD symptoms were associated with greater daily living skills and fewer behavior problems at study start. This study offers some of the first prospective quantitative analyses of behavioral and health life course trajectories in FXS.