Assessment of Symptom Network Density as a Prognostic Marker of Treatment Response in Adolescent Depression

One in 4 adolescents with depression does not respond favorably to treatment.1 Prognostic markers to identify this nonresponder group are lacking and urgently needed.2 It has been suggested that the network structure of depressive symptoms (ie, group-level covariance or connectivity between symptoms) may be informative in this regard.3 Intuitively, one may expect that more densely connected networks would be more inclined to result in negative spirals (eg, sleeplessness causes an individual to be too tired to go out, which leads to a lack of friends, resulting in sadness) and therefore more liable to nonresponse. An influential naturalistic study by van Borkulo et al published in JAMA Psychiatry3 reported that adult patients with depression who continue to experience problems in subsequent years have more densely connected networks at baseline than patients who later recover. Here, we performed a conceptual replication of that study in adolescents with depression who participated in a psychological treatment trial. We tested whether network characteristics at baseline were prognostic for long-term outcomes.1