554. CONNECTING THE TRANSDIAGNOSTIC INTERNALIZING SPECTRUM WITH EPIGENETIC AGING: A HITOP APPROACH

Abstract Background The relative predictive utility for specific forms of internalizing psychopathology (anxiety and depression syndromes) vs. the overall internalizing spectrum has not received extensive attention in the study of epigenetic aging. Here, we took a Hierarchical Taxonomy of Psychopathology (HiTOP) perspective on examining this issue, comparing specific syndromes with the overall internalizing spectrum. Aims & Objectives To compare the predictive utility of specific internalizing syndromes (i.e., major depression, generalized anxiety, and panic disorder) with the overall internalizing spectrum in understanding epigenetic age acceleration (EAA). Method In a national sample of American adults from the Midlife in the United States Study (MIDUS; n=1,309), we compared the prediction of EAA by symptom counts for specific mood and anxiety syndromes (i.e., major depression, generalized anxiety, and panic disorder) with the overall internalizing spectrum (representing the variance in common among these syndromes). Results Later-generation EAA clocks (GrimAge and DunedinPACE) were more strongly associated with the internalizing spectrum than with specific syndromic symptom counts. EAA indices were not significantly associated with the symptom counts net of the internalizing spectrum. Discussion & Conclusions Much of the health-relevant variability within anxiety and depressive disorders is captured by the overarching internalizing spectrum.