A long-term prospective evaluation of first-degree relatives of panic patients who underwent the 35% CO2 challenge.

BACKGROUND: This follow-up study investigated the potential priming effect of the 35% CO2 challenge on the development of anxiety disorders and/or panic attacks in healthy first-degree relatives of panic patients across a period of 3-4 years subsequent to the challenge. METHODS: Thirty-one relatives who underwent the 35% CO2 challenge 3-4 years before and 14 relatives, free from psychiatric diagnoses in the same period, were directly reevaluated for the presence of anxiety disorders and panic attacks. RESULTS: None developed anxiety disorders and only 1, among relatives previously tested with the 35% CO2 challenge, reported sporadic panic attacks. CONCLUSIONS: The 35% CO2 challenge is a safe research paradigm in the investigation of healthy subjects with a familial vulnerability to panic, and CO2 hypersensitivity might be considered a trait marker of an underlying familial vulnerability to panic disorder.

Sensitivity to 35% carbon dioxide in patients with generalized anxiety disorder.

BACKGROUND: Panic disorder and generalized anxiety disorder (GAD) are both characterized by severe anxiety, but there is evidence that indicates a qualitative difference between these 2 anxiety disorders. To investigate the specificity of the association between carbon dioxide (CO2) hypersensitivity and panic disorder and the possible relationships between panic disorder and GAD, the responses to inhalation of a gas mixture of 35% CO2 and 65% oxygen (O2) were assessed. METHOD: Fifteen patients with panic disorder, 13 patients with GAD, and 10 patients with comorbid GAD and panic disorder according to a consensus diagnosis using Diagnostic Interview Schedule Version III-R (DIS-R) and DSM-IV criteria, and 12 healthy controls inhaled 2 vital capacities: 1 of 35% CO2 and 1 of compressed air. A double-blind, randomized, crossover design was used. RESULTS: GAD patients showed reactions to 35% CO2 that were similar to those of healthy controls and significantly weaker than that of panic disorder patients. Patients with comorbid panic disorder and GAD had anxiogenic reactions similar to those of subjects with panic disorder. CONCLUSION: The results of the present study support the idea that panic disorder and GAD are separate disorders that have at least some differences in pathogenetic mechanisms and suggest that the 35% CO2 test might be a valid tool for discriminating between these 2 disorders.

Outcome of patients dropping out from community-based mental health care: a 6-year multiwave follow-up study.

OBJECTIVE: To test three hypotheses: i) is dropping out of community mental health care due to dissatisfaction? ii) Do those who appropriately interrupt mental health care need any more help? iii) Do those who need treatment continue to receive it? METHOD: A cohort from a Community Mental Health Service in Verona, Italy, was followed up for 6 years, interviewing patients at follow-up who are both in contact and not in contact with the service. RESULTS: The main reason for dropping out was service dissatisfaction. Patients still in contact with the service were more often psychotic. Many patients no longer in contact had mild-to-moderate problems, especially anxiety and depression and some social disability. Patients out of contact rarely sought help from other agencies. CONCLUSION: Comprehensive community mental health services seem to offer good continuity of mental health care to patients with psychosis, but dedicate less attention to patients with less severe problems. Some of these patients will go on experiencing a burden of symptoms and disability, over the years.