To examine the correlation of self-reported stress and salivary cortisol, a stress biomarker.
Parents of children with developmental delays (DD) experience higher levels of stress than parents of typically developing children. Roughly one- to two-thirds of parents of children with DD experience clinical levels of parental stress (Davis & Carter, 2008). Children with DD have significantly more behavior problems, experience more emotional difficulties, and are more likely to have clinical levels of behavior problems than typically developing children (Emerson & Einfeld, 2010). Parenting stress and child behavior problems appear to have an interdependent, reciprocal relationship (Neece, Green, & Baker, 2012; Woodman, Mawdsley, & Hauser-Cram, 2015). This relationship, parenting stress and child behavior problems, appears to be responsible for the risks associated with the DD, rather than the delay itself (Herring et al., 2006).
Families of children with DD are susceptible to a range of comorbidities and associated risks including higher levels of parent stress associated with parental depression, more marital conflict, poorer parental physical health, higher child anxiety, poorer child social competence, poorer child emotional regulation, and increased likelihood of a child Attention Deficit Hyperactivity Disorder (ADHD) diagnosis. Additionally, the elevated levels of behavior problems associated with DD puts children at risk for developing future mental disorders such as ADHD and Oppositional Defiance Disorder (Anthony, Bormberg, Gil, & Schanberg, 2011; Baker, Neece, Fenning, Crnic, & Blacher, 2010; Eisenhower, Baker, & Blacher, 2009; Mathis & Bierman, 2015).
One way to intervene to reduce these risks is through mindfulness-based stress reduction (MBSR) with parents of children with DD. MBSR is an empirically based eight-week long training program designed to reduce stress through a series of standardized meditation practices (Kabat-Zinn, 1990). MBSR has been found to be feasible for parents of children with DD (Roberts & Neece, 2015), and has proven effective across multiple outcome measures. After the MBSR intervention, parents of children with DD report significantly less stress, greater practice and experience of mindfulness, increased parenting and life satisfaction, greater self-compassion and well-being, more social interactions with their children, better sleep, and lower levels of depression and anxiety (Bazzano et al., 2015; Dykens, Fisher, Taylor, Lambert, & Miodrag, 2014; Neece 2013; Singh et al., 2007; van der Oord, Bögels, & Peijenburg, 2012). While children do not receive a direct intervention, children’s outcomes after parents’ completion of the MBSR training included significantly reduce behavior problems and increased social skills (Neece, 2014, Singh et al., 2007, van der Oord et al., 2012).
While these self-report and observational improvements are promising, the question arises if biologic measures can further validate these results. Cortisol levels and changes in cortisol levels over the first hour after awakening for the day are sensitive to anticipated demands of the day (Hibel, Mercado, & Trumbell, 2012). Among healthy adults salivary cortisol levels increase by 50 to >100% (Kudielka, Gierens, Hellhammer, Wüst, & Schlotz, 2012). However, this normal physiological response to awakening is significantly altered in individuals experiencing chronic stress (Chida & Steptoe, 2009), and provides a strong biological basis for measuring stress (Chida & Steptoe, 2009; Kudielka et al., 2012). Few studies have examined cortisol in conjunction with MBSR interventions (Dykens, Fisher, Taylor, Lambert, & Miodrag, 2014; Ruiz-Robledillo, Sariñana-González, Pérez-Blasco, González-Bono, & Moya-Albiol, 2015). We therefore set out to explore the association of self-report findings and cortisol response biomarkers to determine the physiological impact of the MBSR intervention on parenting stress.
Methods:
We utilized a randomized, wait-list controlled design with baseline, pre-posttests and six-month follow-up assessments. Participants voluntarily chose to participate in salivary cortisol sample collections (N= 53), and were part of a larger MBSR study involving parents of children with DD between the ages of 2.5 to 5 years. Measures included basic demographics, and Perceived Stress Scale (PSS) at baseline. Measures at pre-post and 6 months follow-up included Parenting Daily Hassles, Life Stressors subscale (PDH-LS), Self-rated stress at the time of saliva collection, and salivary cortisol measured as area under the curve ground (AUCg).
Results:
There were no demographic differences between groups, therefore, results are reported for the combined groups. The majority of the parents participating were mothers (90.6%), married (79.2%), had more than a high school education (69.8%) and about half (50.9%) had a family income of less than $50,000/year. At baseline the mean PSS score was 23.74 (SD 4.53).
Changes over time for PDH-LS, self-reported stress at the time of saliva collection, and AUCg were analyzed using repeated measures ANOVA, a mixed model procedure and Least Squares Means for missing data. Parenting daily hassles reported in terms of how often child and family hassles occurred were significantly reduced (p = .012), and though the intensity of the hassles trended in the desired it did not reach statistical significance. Self-reported stress was decreased at posttest and remained lower at follow-up but did not reach statistical significance. AUCg was reduced at each time point and highly significant (p< .001).
Conclusion:
At baseline participants’ mean PSS score indicates a high perception of stress (Cohen & Janicki-Deverts, 2012). After completion of the MBSR intervention, parents of children with DD reported significantly less parenting stress in terms of how often they experienced child and family hassles. They also reported reduced intensity of these hassles and reduced general stress. Parents’ perceptions of reduced stress was validated physiologically in the significantly reduced AUCg. These biologic stress response reduction results were found both at immediate post-treatment, with sustained results on general stress at 6-months follow-up and continued further reductions of stress by all other measures. Results indicate that MBSR is effective for reducing parenting stress and general stress among parents of children with DD, reinforced by objective biophysiologic data. Of note, biologic markers were even stronger than self-report which are more susceptible to mood changes. The reduction in parenting and general stress through MBSR is promising for this group of highly stressed parents of children with DD, decreasing the likelihood of child behavior complications as well as a myriad of parental comorbidities and poor mental health sequelae.