Early CBT Interventions for prevention of Panic Disorder

Systematic Review

John Sikorski, October 2010

How effective are early cognitive-behavioural interventions in reducing risk of

developing panic disorder (PD) in individuals with a history of infrequent

panic?

Risk Factors for onset of PD Previous history of infrequent panic

attacks (PAs) (Ehlers, 1995)

High level of Anxiety Sensitivity trait (misinterpretation of dangerousness of fear symptoms – not just the original stimulus)

(Reiss et al., 1985; 1986)

Methodology Exclusion criteria:-

Majority of sample with existing PD diagnosis

Non-CBT treatments PAs accounted for by more primary

psychiatric/medical conditions

Methodology Inclusion Criteria:-

Subjects at risk of developing PD (i.e. 1+ infrequent PAs or an above average AS score, measured using ASI)

Preventative studies Controlled clinical trials Brief interventions or components of CBT

treatments

Methodology

Initial Search Strategy:-

PsychINFO; CINAHL; Medline:

Cochrane database; Google Scholar

Methodological Evaluation

CREST rating tool (Peck et al.) Assesses overall research quality

(design + write-up) 42 checkpoints on aspects of

Reliability & Validity 3-point rating scale Calculates % rating for each study

Results = 8 clinical trials 2 brief intervention studies in A&E

settings (Swinson et al., 1992; Nuthall & Townend, 2007)

borderline sample sizes low internal validity high external validity of A&E settings

Results = 8 clinical trials 2 unpublished university dissertations employing

graduates with seemingly minimal clinical qualifications (Abplanalp, 2001; Maltby, 2001)

2 relatively well-designed RCTs, including a carefully-planned, didactic 1 day workshop (Gardenswartz & Craske, 2001) and a computerised self-help course (Kenardy, 2003)

Results = 8 clinical trials 1 sufficiently well-designed, sizeable

(n=114) pilot study in 12 community mental health centres (Meulenbeek et al, 2009)

1 very well-designed, pilot-tested RCT (n=217) run in 17 community mental health centres (Meulenbeek et al., 2010)

Results : Overall study quality

Study CREST rating (%)

Meulenbeek et al. (2010) 86

Kenardy et al. (2006) 74

Gardenswartz & Craske (2001) 71

Meulenbeek et al. (2009) 64

Abplanalp (2001) 63

Maltby (2001) 53

Nuthall & Townend (2007) 39

Swinson et al. (1992) 36

Results : Overall study quality

Studies ranged significantly in terms of design quality

A few statistics from the four best-designed trials……

Meulenbeek (2009) Pilot-study 2 group pre-post design Non-clinical volunteers (n=114) Sub-threshold/mild PD (PDSS score <13) ‘Don’t Panic’ manualised CBT group 8 week vs 12 week course (2 hrs)

Meulenbeek (2009) Large Effect of treatment on panic &

agoraphobia symptoms, measured by PDSS, at 6 months follow up (d=0.71)

8 week course potentially as effective as 12 weeks

Meulenbeek (2010) Multi-site RCT (17 community MH

centres) 2 group pre-post design Adult volunteers (n=217) Sub-threshold/mild PD (PDSS <13) 8 week ‘Don’t Panic’ CBT group vs.

waiting list control

Meulenbeek (2010) 39% (43/109) ‘Don’t Panic’ group achieve

clinically significant change on PDSS, versus 16% (17/108) of control group

Odds ratio for favourable treatment response: OR=3.49, 95% CI 1.77-6.88, p<0.001

Effects maintained at 6 months

Gardenswartz & Craske (2001) Between-groups experiment Undergraduate volunteers (n=121) 1+ Panic Attacks in previous year, but not

satisfying PD diagnosis One 5 hr didactic, group workshop versus waiting

list control Quizzed Participants frequently to check retention 10 min. monthly phonecalls (non-advisory) to

obtain anxiety ratings

Gardenswartz & Craske (2001) Greater decrease in panic symptoms for

workshop group, measured using CIDI (panic section), F(1,120)=4.07, p<0.05

Only 1.8% (workshop group) developed PD at 6 months, versus 13.6% (waiting list control), χ2(1)=5.53, p<0.05

Kenardy et al. (2006) Between groups experiment University students (n=42) with elevated

Anxiety Sensitivity scores (>24 = upper 1/3 on ASI)

Online Anxiety Prevention package

(6 weeks x 5-7 hrs internet self-help) Waiting list control

Kenardy et al. (2006) Initial treatment gains in agoraphobic

cognitions (ACQ) & catastrophic cognitions (CCQ-M) maintained at 6 months

Internet package is not effective in reducing fears of physical sensations (BSQ scores) at 6 months, F(2,80)=1.32, p=0.273

SUMMARY of key findings

Summary: Group interventions Strongest treatment gains were found

from group interventions (n=3)

These studies included all of:-

1. Anxiety education

2. Breathing retraining/relaxation

3. Interoceptive exposure

Summary: Brief interventions

1 of 3 studies suggested a reduction in PA frequency through advising Ps to go back to the panic situation (Swinson et al., 1992)

BUT…. Not sufficiently well-designed or reported

to rely on findings from these 3 studies

Summary: Online self-help

Online panic prevention programs may not be suitable for treating panic

Computerised self-help may be inadequate for the essential (but least tolerated) component of interoceptive exposure

Recommendations: In 4 of 8 studies it may be unwise to rely

on findings, as these were not:

1. Sufficiently well designed/conducted

AND

1. Sufficiently well reported

Recommendations 8 week comprehensive Panic Prevention group

treatments OR

Single 5-hr day workshop, including:1. Panic education2. Breathing retraining3. Interoceptive exposure4. Cognitive restructuring5. + Frequent testing for retention of material