Depression and anxiety are highly comorbid, and this comorbidity is a negative prognostic indicator of treatment outcomes with antidepressant medication. However, research conflicts on the effects of comorbid anxiety on outcomes with cognitive-behavioral therapy (CBT) for depression. The role of comorbid anxiety in treating a subtype of depression, winter seasonal affective disorder (SAD), has yet to be studied. The current project proposes to examine anxiety as both an outcome and a moderator of treatment outcomes in a parent trial comparing light therapy and CBT tailored to SAD (CBT-SAD).
Aim 1 will examine anxiety as an outcome after acute treatment and at a follow-up one winter later.
Aims 2 and 3 will examine baseline anxiety?both dimensional and syndromal anxiety, respectively?as a predictor of SAD treatment outcomes at post-treatment and at a follow-up one winter later. Anxiety disorders will be assessed using the Structured Clinical Interview for DSM-5 (SCID-5) at intake. Anxiety will be dimensionally assessed using the Beck Anxiety Inventory (BAI) at pre-, mid-, and post- treatment, as well as at the one winter follow-up.
Depression comorbid with anxiety is common and associated with worse treatment outcomes. The role of comorbid anxiety in treating a subtype of depression, winter seasonal affective disorder (SAD), has yet to be examined. Using a parent clinical trial comparing the efficacy of light therapy and cognitive-behavioral therapy for SAD, this diversity supplement proposes to examine (1) anxiety as a treatment outcome and (2) the effects of baseline anxiety symptom severity and anxiety disorder diagnostic status on treatment outcomes.
