Medical illness and response to treatment in primary care panic disorder

Received 9 February 2005; received in revised form 16 March 2005; accepted 21 March 2005.

Abstract

Objective

Although studies have suggested that comorbid medical illness can affect the outcome of patients with depression, little is known about whether medical illness comorbidity affects treatment outcome in patients with anxiety.

Method

Primary care patients with panic disorder (n=232), participating in a randomized collaborative care intervention of CBT and pharmacology, were divided into those above (n=125) and below (n=107) the median for burden of chronic medical illness and assessed at 3, 6, 9 and 12 months.

Results

Subjects with a greater burden of medical illness were more psychiatrically ill at baseline, with greater anxiety symptom severity, greater disability and more psychiatric comorbidity. The intervention produced significant and similar increases in amount of evidence-based care, and reductions in clinical symptoms and disability that were comparable in the more and less medically ill groups.

Conclusions

The comparable response of individuals with more severe medical illness suggests that CBT and pharmacotherapy for panic disorder work equally well regardless of medical illness comorbidity. However, the more severe psychiatric illness both at baseline and follow-up in these same individuals suggest that treatment programs may need to be extended in time to optimize treatment outcome.

Keywords: Panic disorder, Medical illness, Outcome, Primary care

a Department of Psychiatry and Behavioral Science, University of Washington School of Medicine at Harborview Medical Center, WA 98104, USA

b Department of Psychiatry, University of California, San Diego, CA, USA

c Department of Family and Preventive Medicine, University of California, San Diego, CA, USA

d Department of Psychology, University of California, Los Angeles, CA, USA

e Department of Psychiatry and Behavioral Science, University of Washington School of Medicine, Seattle, WA 98104, USA

f VA South Central Mental Illness Research Education and Clinical Center (MIRECC), Little Rock, AR, USA

g University of Arkansas for Medical Science, Little Rock, AR, USA

h The RAND Corporation, Santa Monica, CA, USA

Corresponding author. Tel.: +1 206 341 4201; fax: +1 206 731 3236.

PII: S0163-8343(05)00043-5

doi:10.1016/j.genhosppsych.2005.03.007

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