AMHERST, Mass. - Results of a five-year, randomized clinical trial of a new combined treatment approach for severe generalized anxiety disorder (GAD) led by Henny Westra at York University, Toronto, with Michael Constantino at the University of Massachusetts Amherst and Martin Antony at Ryerson University, Toronto, suggest that integrating motivational interviewing (MI) with cognitive behavioral therapy (CBT) improves long-term patient improvement rates than CBT alone.
As psychotherapy researcher Constantino explains, "Generalized anxiety disorder is a very stubborn condition, and even with a full course of CBT, which is the long-time gold standard of treatment, less than half of patients respond. We wanted to do something about improving mental health treatment outcomes for this very commonly encountered disorder." Details appear in an early online issue of the Journal of Consulting and Clinical Psychology.
Westra, Constantino and Antony tested an idea based on preliminary research suggesting that therapists might improve CBT by addressing the observation that patients are very often ambivalent about giving up their worry and anxiety. Constantino says, "People can come into therapy both wanting to change and being reluctant to change. They may be reluctant to let go of something that is so familiar, something that serves as an adaptive tool. That is, the worry is useful to them if they feel it helps keep them on track and functioning responsibly, for example."
Patients talking with a therapist during CBT may reach a place where they have internal ambivalence and begin to more actively resist the therapist's suggestions about ways to change their behavior, the treatment researchers point out. Constantino notes, "This may be what happens in people with GAD to keep treatment from being successful. Our idea is to add MI at that stage to help people to address their ambivalence and any resistances to the therapist or intervention."
MI is an approach that therapists can use to show empathy with the patient's ambivalence, to offer less-directive help for the patient to recognize and to validate their oppositional feelings and reduce the clash between patient and therapist. "Rather than telling you to change, it is helping you to understand why it's hard for you to change," Constantino notes. "Patients tend to get better when MI strategies are used in the face of resistance; they get more out of the therapy."
For this work supported by a grant from the Canadian Institutes of Health Research, the researchers recruited 85 participants in Toronto and randomly assigned 43 of them to receive CBT alone from therapists trained only in CBT, and 42 to receive CBT plus MI from therapists trained in both. Patients attended 15 therapy sessions
Constantino says, "Interestingly, for the main outcomes of worry and of global distress, when assessed immediately after treatment ended, there was no significant effect of treatment condition." However, he adds, "Over a one year post-treatment follow-up period, we saw patients who received the combined MI-CBT therapy do significantly better on both of these outcome variables. They did much better than the CBT-only patients, who either stayed the same or got worse in their worry and distress. So it was a sleeper effect, they got better but we didn't see it until later."
He adds, "We think that because MI is more patient-centered, those who got MI were better equipped to resolve their own struggles and challenges after therapy ended, even though they didn't have the help of a therapist anymore. We believe that MI strategies may give them more autonomy, and may help them help themselves more readily over the long term."
In one of their many follow-up analyses, Constantino says preliminary results suggest that patients in the combination MI-CBT group were less resistant to the therapist, as coded by an observer. Further, this difference statistically accounted for the beneficial effects over the follow-up period of integrating MI with CBT.
Enjoying a remarkable follow-up participation rate of 97 percent among this study's subjects, the researchers are currently conducting multiple secondary studies to explore the results. "One thing we don't know yet is why the groups didn't differ immediately at post-treatment," Constantino notes.
Perhaps a more daunting problem for the research team will be to disseminate their findings among psychotherapists to help them better help their patients, he adds. "Psychotherapy works," Constantino says. "It is definitely better than nothing, but it doesn't work the same for everybody. We also know that it can always be improved. Ideally, this new knowledge will turn into workshops and enter the mainstream in new teaching methods and as we train next-generation psychology students. As a field, we keep trying to get better at this."