Childhood separation anxiety disorder can heighten the risk for panic disorder in early adulthood, and both separation anxiety disorder and panic disorder are associated with heightened sensitivity to inhaled CO2 and can be influenced by childhood parental loss, according to a NARSAD-funded study published in the January 2009 issue of Archives of General Psychiatry, a journal published by the American Medical Association.
The research was led by Marco Battaglia M.D., of San Raffaele University, in Milan, Italy, a two-time NARSAD Independent Investigator Award recipient, with colleagues from the Queensland Institute of Medical Research, in Brisbane, Australia, the Virginia Institute of Psychiatric and Behavioral Genetics at Virginia Commonwealth University and the Norwegian Institute of Public Health, Oslo.
While a role for early losses in raising the risk for panic disorder has frequently been hypothesized, Dr. Battaglia noted that the causes of these complex reciprocal relationships had long remained unclear, and the different aspects of the puzzle often were studied separately. In their research, Dr. Battaglia and his team interviewed more than 700 young adults from the Norwegian Institute of Public Health Twin Panel general population cohort. The subjects were questioned regarding lifetime prevalence of mental disorders, history of childhood parental loss and separation anxiety disorder symptoms, and their responses to a CO2-enriched mixture versus a compressed air placebo were assessed.
Dr. Battaglia explained that while shared genetic determinants appear to be the major, underlying cause of the developmental continuity of childhood separation anxiety disorder into adult panic disorder, and of the association of both disorders with heightened sensitivity to CO2, the data also show the importance of early events of separation. Inasmuch as childhood parental loss is a truly environmental risk factor uninfluenced by genetic factors, it can further affect susceptibility to panic disorder and perhaps alter an individual’s respiratory physiology for a long time.
Among the implications of this study, Dr. Battaglia stated, children who display high separation anxiety and/or experience early losses (including parental death, separation and divorce) merit particular societal and professional attention in order to prevent or to diagnose early symptoms of anxiety and panic. A further suggestion is that investigational strategies that stem from both the biological and the sociological approach to mental health can coexist within a twin design and provide valuable reciprocal cross-fertilization.