“My major research interest is in understanding the co-occurrence of psychological disorders and medical conditions. We see high rates of depression in people with obesity,” said Pagoto, who helped develop the behavioral treatment track at the UMass Memorial Weight Center. At the center, they translated the Diabetes Prevention Program (DPP), a proven behavioral weight loss intervention, into a successful hospital-based weight loss program in 2004. “When a psychological disorder occurs with a medical illness, we often see that it affects the disease severity, complication rates and even mortality rates.”
But while separate treatments for obesity and depression have been studied extensively in clinical trials, less closely examined has been the question of how to treat them as interrelated conditions. “Research is often very condition-specific, but clinical patients don’t come in with one condition, so treating them can often be more complex than what the trials show us,” Pagoto explained. “The challenge is what to do when you’re in the clinic, looking at clinical research that may not reflect who you’re working with.”
After identifying that fully 60 percent of obese patients seeking weight loss treatment at the Weight Center also have psychological disorders like depression that are associated with poor weight loss outcomes, the troubling question is, “Which weight loss treatment should we use for this population?”
While UMass Memorial patients without psychological co-morbidities closely paralleled the outcomes of the original DPP trial, in which fully 49 percent of participants achieved or exceeded the goal of a 7 percent weight loss, only about one in five of the 60 percent of UMass Memorial patients with psychological co-morbidities attained the goal. “Outcomes for groups with psychological co-morbidities are discouraging, especially given the intensity and expense of behavioral weight loss treatment,” Pagoto said. “Should we be sending people with psychological disorders into intensive and expensive weight loss treatment, knowing that the majority may not do well? What are implications of weight loss treatment failure on the co-morbid psychological condition?”
These concerns led to Pagoto’s National Institute of Mental Health-funded study, Treating Co-Morbid Obesity and Major Depressive Disorder, a randomized clinical trial of 154 overweight women with major depressive disorder to see if treating depression first could improve weight- loss outcomes. The study compared two interventions, one the standard six-month DPP, the other providing Behavioral Activation (BA) therapy, a proven short-term behavioral intervention for depression (for which Pagoto co-wrote the most recent manual), for 10 weeks prior to the DPP weight-loss intervention for the remainder of the six months.
Results showed that people who improved in their depression were able to lose clinically significant weight, while those whose depression did not improve did not lose weight.
These findings suggest that weight loss success may require resolution of psychological symptoms, like depression. Acknowledging again the gap between research and practice that she continually seeks to close, her take-away messages were nonetheless straightforward: “Consider co-morbid conditions when translating research into practice.” Equally important is her corollary to that rule: “Patients are the richest source for research ideas.”
Related links on UMassMedNow:EXPERT’S CORNER: Sherry Pagoto on five keys to weight lossNewsmaker: Sherry Pagoto on emotional eating studyNewsmaker: Sherry Pagoto on virtual coaching and weight loss‘Whole patient’ care urged by UMMS psychologist