Contribution of early‐life unpredictability to neuropsychiatric symptom patterns in adulthood

Background Recent studies in both human and experimental animals have identified fragmented and unpredictable parental and environmental signals as a novel source of early‐life adversity. Early‐life unpredictability may be a fundamental developmental factor that impacts brain development, including reward and emotional memory circuits, affecting the risk for psychopathology later in life. Here, we tested the hypothesis that self‐reported early‐life unpredictability is associated with psychiatric symptoms in adult clinical populations. Methods Using the newly validated Questionnaire of Unpredictability in Childhood, we assessed early‐life unpredictability in 156 trauma‐exposed adults, of which 65% sought treatment for mood, anxiety, and/or posttraumatic stress disorder (PTSD) symptoms. All participants completed symptom measures of PTSD, depression and anhedonia, anxiety, alcohol use, and chronic pain. Relative contributions of early‐life unpredictability versus childhood trauma and associations with longitudinal outcomes over a 6‐month period were determined. Results Early‐life unpredictability, independent of childhood trauma, was significantly associated with higher depression, anxiety symptoms, and anhedonia, and was related to higher overall symptom ratings across time. Early‐life unpredictability was also associated with suicidal ideation, but not alcohol use or pain symptoms. Conclusions Early‐life unpredictability is an independent and consistent predictor of specific adult psychiatric symptoms, providing impetus for studying mechanisms of its effects on the developing brain that promote risk for psychopathology.