Respiratory Dysregulation and Breathing Training in Anxious Outpatients

In clinic testing and outside the clinic testing, we will assess the prevalence of respiratory dysregulation in a sample of 60 non-psychotic, not currently alcohol or drug abusing veteran outpatients from our MHC (Mental Hygiene Clinic) who experience episodic anxiety but who do not qualify and have never qualified for the diagnosis of PD (panic disorder). These patients will be compared to 30 patients who are not clinically anxious. Of these 60 anxious patients, 30 will be randomly assigned to a 4-week course of breathing training assisted by feedback of end-tidal pCO2 levels as an augmentation of their current treatment. They will be compared to 30 who simply will continue with their current treatment (TAU). The breathing training group will receive clinical and physiological assessments immediately before the treatment period, four weeks after the end of the treatment period, and at a 4-month follow-up. The TAU group will be assessed three times at equivalent intervals, and if they wish, may undergo breathing training after the third assessment. Treatment will take place mainly in the first two years, giving us adequate time for follow-up and data analysis. We expect that this therapy will be especially effective for treating anxiety in the patients with substantial respiratory dysregulation.

Inclusion criteria

• Patients must be rated 2 or more on both Q1 and Q3, but they must not meet the full criteria for PD as determined by the Anxiety Disorders Interview Schedule for DSM-IV-Lifetime Version (ADIS).
• In addition, they must be clinically stable enough that changes in the patients' anxiety levels can be attributed to the breathing training rather than to other new treatment initiatives during the training and 1-month evaluation periods or to spontaneous fluctuations in anxiety levels. Thus, potential participants taking SSRIs or other antidepressants, or benzodiazepines have to have been on a stable dose of these medicines for at least the previous two months.

Exclusion criteria

• Potential participants taking short-acting benzodiazepines such as alprazolam in excess of 2.0 mg/day or the equivalent on any day in the past month are excluded, because improvement might show up only in terms of reduction of medication dosage and not on the evaluation measures planned.