2004 overview: Developments in the treatment of anxiety disorders

In this overview Professor Charles Pull, Luxemburg, discusses some of the issues in anxiety disorders that attracted special interest in 2004.

The treatments of choice for anxiety disorders are cognitive behavioural therapy (CBT) and/or pharmacotherapy (in particular selective serotonine reuptake inhibitors). The main component of CBT for anxiety disorders is graded exposure therapy during which the patient learns to confront the stimuli he/she is afraid of. Graded exposure leads to fear habituation and fear extinction.

Although exposure therapy is highly effective, only a limited proportion of patients can benefit from the treatment, since the demand largely exceeds the availability of trained therapists. As such, there is a need for methods that may reduce the time spent with a clinician.

Three such methods have been developed in recent years and/or have become prominent in 2004: computer-aided self-treatment, virtual reality exposure therapy, and use of cognitive enhancers to facilitate extinction of fear.

Computer-aided self-treatment

In computer-aided self-treatment, routine aspects of CBT are delegated to computer guidance. Patients interact with a computer system that asks the questions and uses patients' answers to direct the interview and give individually tailored advice. In the systems reviewed below, the clinician uses his/her time to screen patients at the start, and to give brief back-up advice if required. If patients get stuck, they can obtain brief live advice from a therapist on a phone helpline.

Marks et al. have developed a computer-guided system called FearFighter that provides guidance for patients suffering from phobic disorder or panic disorder. According to a recent study (ref. 1), sufferers who were treated in clinics improved as much after guidance mainly by FearFighter as after guidance entirely by a clinician.

The program can also been accessed on the Internet with patients being able to ask for brief therapist support by telephone. Results from an open study (ref. 2) have shown that the outcome and satisfaction in patients who accessed the program through the Internet resembled those in patients with similar disorders who used FearFighter in clinics with brief face-to-face therapist support.

In another study (ref. 3) on computer-aided CBT self-help for anxiety and depressive disorders, sufferers improved by using one of four computer-aided systems of cognitive behaviour therapy (CBT) self-help for phobia/panic, depression, obsessive-compulsive disorder, and general anxiety.

A recent case study (ref. 4) describes the application of a palmtop computer-assisted therapy in a patient suffering from social phobia. The computer program includes a diary function for ongoing self-monitoring of anxiety as well as guidance on the practice of relaxation, cognitive restructuring, and self-control desensitization. The patient carried the ambulatory computer throughout this treatment. Outcome data suggest that the treatment was highly effective.

Virtual reality exposure therapy

Virtual Reality Exposure Therapy (VRET) uses virtual environments to expose subjects to specified stimuli. In the treatment of anxiety disorders, VRET is used to gradually expose subjects to virtual people (avatars), animals (e.g. spiders), or situations (e.g. heights, closed as well as empty spaces, combat) that he/she is afraid of.

Four reviews and three controlled studies have been published in 2004 on the use of VRET in anxiety disorders.

Reviews by Botella et al. (ref. 5) , Krijn et al. (ref. 6), Wiederhold and Wiederhold (ref. 7) and Pull (ref. 8) highlight the potential of VRET in the treatment of several anxiety disorders, including the treatment of specific phobias (fear of flying, acrophobia, fear of driving, claustrophobia and fear of spiders), social anxiety disorder, post-traumatic stress disorder and panic disorder with or without agoraphobia.

In a randomised controlled study, Krijn et al. (ref. 9)have investigated the effects of virtual reality exposure therapy (VRET) in acrophobia. Feelings of presence were systematically varied by using either a head-mounted display (HMD) (low presence) or a computer automatic virtual environment (CAVE) (high presence). VRET in general was found to be more effective than no treatment.

No differences were found in effectiveness between VRET using an HMD or CAVE. Results were maintained at 6 months follow-up. Results of VRET were comparable with those of exposure in vivo.

Klinger et al. (ref. 10, ref. 11), have published reports of a controlled study using virtual reality techniques to treat generalized social phobia. The virtual environments used in the treatment reproduce four situations that patients with social phobia feel the most threatening: performance, intimacy, scrutiny and assertiveness.

According to preliminary results, total scores and sub-scores (social fear and performance fear) on the Liebowitz Social Anxiety Scale, as well as scores on other instruments measuring outcome were considerably reduced at post-test in both treatment groups.

In an ongoing, randomised controlled study by Botella et al. (ref. 12, ref. 13), patients with or without agoraphobia are assigned to either VRET, to exposure in vivo, or to a waiting list control group.

Initial results of the study indicate that patients in the VRET and in the CBT groups improve significantly more than patients in the waiting list control group, and that there are no significant differences in outcome measures between patients treated by VRET and patients treated by exposure in vivo.

Cognitive enhancers

Another new way to approach the treatment of anxiety disorders is to use substances that are involved in the process of learning and to determine whether a combination of such substances with exposure therapy may speed up the process of fear extinction.

One of the substances that have been suggested to be putative cognitive enhancers is D-cycloserine (DCS), a partial agonist at the N-methyl-D-aspartate (NMDA) glutamatergic receptor. In particular, DCS has been shown to improve NMDA synaptic transmission and to facilitate extinction of fear in rats (ref. 14).

Ressler et al. (ref. 15) have published an exciting study on the use of D-cycloserine (DCS) as a cognitive enhancer of fear extinction in patients with acrophobia. In a double-blind, randomised controlled study, 27 patients with acrophobia were assigned to treatment with behavioural exposure therapy plus placebo, or to behavioural exposure therapy plus D-cycloserine.

Treatment consisted in two therapy sessions, separated by 1 to 2 weeks. Participants were instructed to take the study medication 2 to 4 hours before each one of the two VRET sessions.

Post-treatment assessment at 1 week and three months of general avoidance of heights, and of general attitudes towards heights, showed significantly more improvement in the DCS groups. In addition, patients in the DCS groups reported a significantly bigger increase of exposures in the real world than those in the placebo group.

Looking ahead

Anxiety disorders are highly prevalent and disabling mental disorders. As such, and although there are highly efficient, empirically validated therapies, including pharmacotherapy as well as psychotherapy, there is a need for strategies that may facilitate and/or enhance currently available treatments.

Computer-aided self-treatment, virtual reality exposure therapy, and use of cognitive enhancers to facilitate extinction of fear, are among the strategies that have become prominent in 2004, and that will probably play a major role in the field in the years to come.

References

1. Marks IM., Kenwright M, McDonough M, Whittaker M, Mataix-Cols D. Saving clinicians' time by delegating routine aspects of therapy to a computer: a randomized controlled trial in phobia/panic disorder. Psychological Medicine 2004; 34; 9-17.

2. Kenwright M, Marks IM. Computer-aided self-help for phobia/panic via Internet at home: a pilot study. British Journal of Psychiatry 2004; 184; 448-9.

3. Gega L, Marks I, Mataix-Cols D. Computer-aided CBT self-help for anxiety and depressive disorders: experience of a London clinic and future directions. Journal of Clinical Psychology 2004; 60; 147-57.

4. Przeworski A., Newman MG. Palmtop computer-assisted group therapy for social phobia. Journal of Clinical Psychology 2004; 60; 179-88.

5. Botella C, Quero S, Banos RM, Perpina C, Garcia Palacios A, Riva G. Virtual reality and psychotherapy. Studies in Health Technology and Informatics 2004; 99; 37-54.

6. Krijn M, Emmelkamp PMG, Olafsson RP, Biedmond R. Virtual reality exposure therapy of anxiety disorders: a review. Clinical Psychology Review 2004; 24; 259-281.

7. Wiederhold BK and Wiederhold MD. Virtual Reality Therapy for Anxiety Disorders: Advances in Education and Treatment. American Psychiatric Association, 216 pages.

8. Pull C. Current status of Virtual Reality Exposure Therapy in Anxiety Disorders. Current Opinion in Psychiatry (in press).

9. Krijn M, Emmelkamp PMG, Biemond R, de Wilde de Ligny C, Schuemie MJ, van der Mast CA. Treatment of acrophobia in virtual reality: The role of immersion and presence. Behaviour Research and Therapy 2004; 42; 229-239.

10. Klinger E, Legeron P, Roy S, Chemin I, Lauer F, Nugues P. Virtual reality exposure in the treatment of social phobia. Studies in Health Technology and Informatics 2004; 99; 91-119.

11. Klinger E, Légeron P, Roy S, Chemin I, Lauer F, Nugues P. (2004). Virtual Reality Exposure in the Treatment of Social Phobia. In : G. Riva, C. Botella, P. Légeron, G. Optale (Eds.), Cybertherapy: Internet and Virtual Reality as Assessment and Rehabilitation Tools for Clinical Psychology and Neuroscience, Amsterdam: Ios Press, 2004.

12. Botella C, Villa H, Garcia Palacios A, Quero S, Banos RM, Alcaniz M. The use of VR in the treatment of panic disorders and agoraphobia. Studies in Health Technology and Informatics 2004; 99; 73-90.

13. Botella C, Villa H, Garcia-Palacios A, Quero S, Banos RM, Alcaniz M. (2004). The use of virtual reality in the treatment of panic and agoraphobia. In : G. Riva, C. Botella, P. Légeron, G. Optale (Eds.), Cybertherapy: Internet and Virtual Reality as Assessment and Rehabilitation Tools for Clinical Psychology and Neuroscience, Amsterdam: Ios Press, 2004.

14. Walker DL, Ressler KJ, Lu KT, Davis M. Facilitation of conditioned fear extinction by systemic administration or intra-amygdala infusions of D-cycloserine as assessed with fear-potentiated startle in rats. Journal of Neurosciences 2002; 22; 2343-51 (Note: Free full text article)

15. Ressler KJ, Rothbaum BO, Tannenbaum L, Anderson P, Graap K, Zimand E, Hodges L, Davis M. Cognitive Enhancers as Adjuncts to Psychotherapy. Use of D-Cycloserine in Phobic Individuals to Facilitate Extinction of Fear. Archives of General Psychiatry 2004; 61; 1136-1144.