3 - (SYM23) CBT for Depression Reduces Symptoms of Anhedonia but Does Not Increase Positive Affect

Depressed patients often see the restoration of positive mood as their top priority treatment goal (Demyttenaere et al., 2015). This goal could be assessed in two ways. First, it might be assessed as a reduction in anhedonia. Symptoms of anhedonia, or diminished pleasure, are one of the two sets of mood symptoms required for a diagnosis of depression in the DSM. Second, it might be assessed as an increase in the experience of positive affect. Positive affect (PA) is commonly assessed with the Positive and Negative Affect Scale (PANAS), which asks the respondent to self-rate their experience of 10 high activation positive emotions (interested, excited, strong, enthusiastic, proud, alert, inspired, determined, attentive, active).

Although quite a bit of data show that CBT reduces symptoms of depression, less is known about CBT’s effects on symptoms of anhedonia and positive affect (Craske, et al., 2016). To address these questions, we examined changes in symptoms of anhedonia during CBT for depression in three outpatient samples (one naturalistic sample of patients treated in private practice and two samples of patients treated in randomized controlled trials), and changes in PA for a subset of the naturalistic sample.

We assessed symptoms of anhedonia using a validated measure (Cogan et al., 2023) that relies on four items from the Beck Depression Inventory. We assessed the other symptoms of depression using all the other items from the BDI. We assessed PA with the PANAS. We studied a naturalistic sample of 317 depressed outpatients treated with CBT in private practice and in two randomized trials (Jacobson et al., 1996; Elkin et al., 1989). In all three samples the proportion of patients showing reliable change in symptoms of anhedonia was not statistically significantly different from the proportion of patients showing change in all other symptoms of depression. A subsample of 44 patients in the naturalistic sample completed the PANAS weekly; when we examined change over 12 weeks, PA changed less than NA (these data were published in Kring et al., 2007). We conclude that symptoms of anhedonia and high energy positive affect are distinct phenomena and respond differently to outpatient CBT for depression.