A review of more than 50 clinical trials has found that psychological and behavioral therapies may serve as effective non-drug treatments for reducing disease-causing inflammation in the body. The results of the , published in JAMA Psychiatry, also show that cognitive behavior therapy, or CBT, is superior to other psychotherapies at boosting the immune system.
The study's senior author, George Slavich, director of the , and two colleagues, from UC Davis and San Diego State University, looked at whether interventions typically used for treating mental health problems such as anxiety and depression might also enhance biological processes involved in physical health.
They examined the results of 56 randomized clinical trials involving more than 4,000 people in which participants receiving psychotherapeutic interventions were also assessed immunologically. The researchers analyzed the duration and type of psychotherapy received — including whether it was group or non-group therapy — as well as how the treatments affected various markers of inflammation and other immune system processes in the body.
"People automatically go to medication first to reduce chronic inflammation, but medications can be expensive and sometimes have adverse side effects," Slavich said. "In this review, we wanted to know whether psychotherapies can also affect the immune system and, if so, which ones have the most beneficial effects over the long term."
Slavich and his colleagues compared results from clinical trials that investigated the effects of several types of intervention, including CBT, CBT plus medication, grief and bereavement support, a combination of two or more psychotherapies, and psychoeducation, among others.
"This seems to be a case of mind over matter," Slavich said. "Psychotherapies like CBT can change how we think about ourselves and the world, and changing these perceptions can in turn affect our biology. The results of this study take this idea one step further and suggest that psychotherapy may be an effective and relatively affordable strategy for reducing individuals' risk for chronic diseases that involve inflammation."
In seeking to better understand how the body reacts to non-drug treatments for chronic inflammation, the researchers looked at several immune outcomes from the clinical trials. Of those outcomes, pro-inflammatory cytokines were most strongly affected by psychotherapy in general and CBT in particular. These cytokines are notable because they help the immune system heal physical wounds and fight infections. But if they remain persistently elevated, they can lead to chronic inflammation, increasing the risk of physical illnesses such as heart disease, cancer and Alzheimer's disease, as well as mental health problems like anxiety disorders, depression, >post-traumatic stress disorder, schizophrenia, self-harm and suicide.
"There are many people who would prefer to use non-drug interventions for improving their immune system function," Slavich said. "In some cases, they can't take certain medications because of medical reasons, and in other instances, the medications they need are too expensive. And then there are people who simply prefer a more holistic approach to improving their health."
Slavich said that these findings provide strong evidence that psychotherapy may be helpful in this regard.
"Out of all of the interventions we examined, CBT was the most effective for reducing inflammation, followed by multiple or combined interventions," he said. "Moreover, we found that the benefits of CBT on the immune system last for at least six months following treatment. Therefore, if you're looking for a well-tested, non-drug intervention for improving immune-related health, CBT is probably your best choice."
