Salivary Diurnal Cortisol Predicts Post-Traumatic Stress Symptoms in Parents of Infants With Congenital Heart Disease

Background: Parents of infants born with congenital heart disease (CHD) who require open heart surgery after birth are at risk for prolonged psychological distress. Even after their infants are discharged, parents may experience anxiety, depressive, and post-traumatic stress (PTS) symptoms; yet, it is unclear which parents are at greater risk for ongoing symptoms. The purpose of this study was to explore whether measures of the biomarker cortisol in parents during their infants' postoperative period were associated with subsequent psychological distress symptoms at three-month post discharge. Methods: This was a prospective, longitudinal exploratory study of 40 parents of infants with CHD after open heart surgery using consecutive enrollment. Parents provided diurnal saliva samples for two consecutive days in the postoperative period. Six predictors were summarized and generated including waking cortisol, bedtime cortisol, cortisol awaking response, area under curve with respect to the ground (AUCg), cortisol index, and cortisol slope. Self-report outcome measures on anxiety, depressive, and PTS symptoms were collected three-months post-discharge. Linear mixed models examined the associations between each predictor and each outcome while accounting for within-dyad variance using an unstructured covariance matrix. Results: Cortisol AUCg was a predictor of PTS at three-months post-discharge (beta = .34, p = .03, Cohen's d = 2.05). No significant relationships were found with the other cortisol measures. Conclusions & Implications: Findings suggest that cortisol area under curve may help to identify parents at risk for increased PTS in the months following their infants' hospitalization for cardiac surgery, serving as a foundation for future study in this area.