Motor Abnormalities, Depression Risk, and Clinical Course in Adolescence

Background: Motor abnormalities, such as psychomotor agitation and retardation, are widely recognized as core features of depression. However, it is not currently known whether motor abnormalities connote risk for depression. Methods: Using data from the Adolescent Brain Cognitive Development (ABCD) Study, a nationally representative sample of youth (N = 10,835, 9–11 years old), the present paper examines whether motor abnormalities are associated with 1) depression symptoms in early adolescence, 2) familial risk for depression (familial risk loading), and 3) future depression symptoms. Motor abnormality measures included traditional (DSM) motor signs such as psychomotor agitation and retardation as well as other motor domains such as developmental motor delays and dyscoordination. Results: Traditional motor abnormalities were less prevalent (agitation = 3.2%, retardation = 0.3%) than nontraditional domains (delays = 13.79%, coordination = 35.5%) among adolescents. Motor dysfunction was associated with depression symptoms (Cohen's d = 0.02 to 0.12). Familial risk for depression was related to motor abnormalities (Cohen's d = 0.08 to 0.27), with the exception of motor retardation. Family vulnerability varied in sensitivity to depression risk (e.g., retardation: 0.53%; dyscoordination: 32.05%). Baseline endorsement of motor abnormalities predicted future depression symptoms at 1-year follow-up. Conclusions: These findings suggest that motor signs reflect a novel, promising future direction for examining vulnerability to depression risk in early adolescence.