We found that addition of GSH to UC improved subjective health at 3 months more than UC alone did. The treatment effect was of moderate size with a 13% difference between treatment arms in participants rating themselves as better or much better (corresponding to a NNT of 8). Taking these results together with the greater improvements in presenting symptoms, reduced symptom burden, less health anxiety and greater satisfaction with care, the chronicity of the patients' illnesses, and the simplicity of the intervention and its safety, we believe that the observed treatment effect is clinically useful.
At the 6-month follow-up, the additional effect of GSH on improvement in subjective health was smaller (OR 1.45) and no longer statistically significant. There was, however, a greater improvement in presenting symptoms, less belief in the symptoms being permanent, greater satisfaction with care, and a clinically significant 11-point difference on the SF-12 physical functioning scale.22
The smaller treatment effect on the primary outcome at follow-up suggests that future studies should test the effect of adding a maintenance phase to the GSH guidance.
There are limitations to this study. Although the sample of patients recruited was identified by screening and therefore more likely to be representative of patients attending neurology clinics than of referrals, the proportion reported as having functional symptoms (16%) was smaller and the severity of their illness was greater than expected from previous surveys.5,23
This finding suggests that neurologists were selecting which patients to refer. We included patients with a variety of symptoms, and the resulting heterogeneity potentially obscures the size of the treatment effect for individual symptoms. Although there is always a lack of certainty that symptoms are definitely functional and not indicative of organic disease, follow-up evidence from the same services suggests that the diagnosis is rarely wrong.23
Even if organic disease subsequently emerges, as long as GSH is given as a supplement to rather than as a replacement for UC, no harm is likely to result. The UC given to participants in the trial was enhanced by informing the patients' primary care doctors of the outcome of the psychiatric assessment. Although the clinicians who provided GSH were trained in CBT, we know from adherence ratings of session recordings that they provided only guidance and not CBT. Because participants allocated to GSH received a complex intervention of workbook, attention, and face-to-face guidance sessions, we cannot identify which of these components was the most important. Our outcomes were measured by self-report, reflecting the subjective nature of the problems we were treating. However, the nature of the treatments meant that participants could not be blinded to their allocation, which could have potentially biased their outcome ratings. Finally, the follow-up period was relatively short, given the chronicity of the patients' illnesses. Future effectiveness studies should examine longer-term outcomes as well as costs.
There are many uncertainties about how best to manage this large and important group of patients. First, what should the treatment be? Whereas intensive psychologically oriented CBT is effective for patients with functional symptoms who seek it,24,25
we have found that CBT based on a functional explanation can be acceptable to relatively unselected neurology patients. Second, where should treatment be delivered? Although most previous studies have included only patients willing to attend mental health services,26–28
this trial shows that treatment can be provided in neurology clinics.29
Third, who should deliver treatment? CBT delivered by trained therapists is expensive to provide, and therapists may simply not be available. Primary care physicians can be trained to provide psychological treatment for functional symptoms, but this has been found to be of limited efficacy, in part because of the difficulty of delivering it in routine practice30,31
; treatment by medical specialists is likely to have similar limitations. This trial suggests that CBT given as GSH offers a potentially widely available, effective, and cost-effective treatment for the large number of neurology patients with functional symptoms.
This trial provides initial evidence that CBT-based GSH for neurology patients with functional symptoms is feasible to deliver and acceptable to the patients and produces better outcomes than UC alone, at least in the short term. It therefore offers a novel and potentially useful first step in improving the management of functional symptoms. Further development of this form of treatment to increase its effectiveness and to evaluate its cost-effectiveness is required. We also hope that this trial encourages others in interdisciplinary treatment research for patients with this problem.