Is a severe clinical profile an effect modifier in a web-based depression treatment for adults with type 1 or type 2 diabetes? Secondary analyses from a randomized controlled trial

Background: depression and diabetes are two highly prevalent and co-occurring health problems. web-based,diabetes-specific cognitive behavioral therapy (cbt) depression treatment is effective in diabetes patients,and has the potential to be cost effective and to have large reach. a remaining question is whether the effectiveness differs between patients with seriously impaired mental health and patients with less severe mental health problems. objective: to test whether the effectiveness of an eight-lesson web-based,diabetes-specific cbt for depression,with minimal therapist support,differs in patients with or without diagnosed major depressive disorder (mdd),diagnosed anxiety disorder,or elevated diabetes-specific emotional distress (dm-distress). methods: we used data of 255 patients with diabetes with elevated depression scores,who were recruited via an open access website for participation in a randomized controlled trial,conducted in 2008-2009,comparing a diabetes-specific,web-based,therapist-supported cbt with a 12-week waiting-list control group. we performed secondary analyses on these data to study whether mdd or anxiety disorder (measured using a telephone-administered diagnostic interview) and elevated dm-distress (online self-reported) are effect modifiers in the treatment of depressive symptoms (online self-reported) with web-based diabetes-specific cbt. results: mdd,anxiety disorder,and elevated dm-distress were not significant effect modifiers in the treatment of self-assessed depressive symptoms with web-based diabetes-specific cbt. conclusions: this web-based diabetes-specific cbt depression treatment is suitable for use in patients with severe mental health problems and those with a less severe clinical profile.