Daily Stress and Cortisol Patterns in Parents of Adult Children with a Serious Mental Illness

Barker, E.T., Greenberg, J.S., Mailick Selzer, M., & Almeida, D.M. (2011, September 5). Daily stress and cortisol patterns in parents of adult children with a serious mental illness. Health Psychology. Advance online publication. doi: 10.1037/ a0025325

Much research has been done on the psychological impact of parenting an adult child with a severe mental illness. Little has been done on the physiological impact, however.

The hormone cortisol is active in mediating the effects of life stressors on physical health. Over time, exposure to chronic stress can lead to flatter profiles and overall lower levels of circulating cortisol. This is a pattern of hypoactivity that is symptomatic of wear and tear on the HPA axis.  

Previous research shows that cortisol is found to diminish less in days that parents of these adult children with serious mental illnesses spend time with their children. In a study of mothers of adult children with autism, the mothers showed a flatter cortisol awakening response on days after the children had an increase in behavioral problems. In another study of parents whose son or daughter had schizophrenia, parents whose son or daughter was not institutionalized had a flatter cortisol awakening response than parents whose child was institutionalized.

In this study, the researchers examined the cortisol awakening response and daily decline in parents in a sample of parents whose children have a severe mental illness. They compared this to a control group of parents with non-disabled children.

The hypothesis was that parents of children with a severe mental illness would have a flatter CAR and a flatter decline in cortisol on days after more severe stress. All of the participants completed an identical data collection protocol based on the methodology developed for the National Study of Daily Experiences. There were eight days of telephone interviews and four days of saliva collection.  The participants included 37 (22 mothers and 15 fathers) that had an adult child with a serious mental illness. Seventeen of the children had bipolar disorder, eight had schizophrenia, and twelve had major depression. Those aforementioned participants were drawn from the MIDUS study. An additional 24 parents (11 mothers and 13 fathers) identified in the Wisconsin Longitudinal Study participated in the NSDE study. Of the children of those parents, seven had bipolar disorder, six had schizophrenia, and 11 had major depression). A comparison sample of 321 parents with at least one child but none with a severe mental illness were drawn from the MIDUS study for a control.

Of the parents of children with an SMI, 46% were fathers, 72% were married, 59% had completed some post-secondary education, and all were white. The average age was 60.07 years. In the control group, 51% were fathers, 82% were married, 69% had completed some post-secondary education, and 93% were white. The average age was 58.09 years.

The number of daily stressors was evaluated at the end of each of the eight days. This was done by phone interviews and the measure used was the Daily Inventory of Stressful Events. A score of 0 indicated no stressful events, while a score of 28 indicated stressful events in each of seven categories.

On days two through five, the parents collected four cortisol samples throughout the day (upon wakening, 30 minutes out of bed, before lunch, and at bedtime). They analyzed only the first two samples and the bedtime sample, because those are used to look at CAR and the daily decline. The researchers calculated the CAR for each participant by subtracting the waking values from the 30 minutes after waking values. They calculated daily decline by subtracting the bed time values from the 30 minutes after waking values. The parent participants also indicated whether or not they were taking any medications.

Results from this study indicated that parents with a child with a severe mental illness experienced more stressful events and had higher ratings of stress severity than the control group. They also had less of a decrease in circling cortisol from waking to sleeping. Additionally, these parents were more likely to be taking anxiety or depression medications.

This study adds to the growing body of research that indicates negative aging effects on raising a child with a mental illness.