Unwanted outcomes in cognitive behavior therapy for pathological health anxiety: a systematic review and a secondary original study of two randomized controlled trials.

INTRODUCTION

Cognitive behavior therapy (CBT) is effective for pathological health anxiety, but little is known about unwanted outcomes.

AREAS COVERED

We investigated unwanted outcomes in the form of adverse events, overall symptom deterioration, and dropouts in CBT for pathological health anxiety based on a systematic review of 19 randomized controlled trials (PubMed, PsycInfo, and OATD; last updated 2 June 2023; pooled  = 2188), and then a secondary original study of two randomized controlled trials (pooled  = 336). In the systematic review, 10% of participants in CBT reported at least one adverse event and 17% dropped out. Heterogeneity was substantial. In the original investigation, 17% reported at least one adverse event, 0-10% met criteria for overall symptom deterioration, and 10-19% dropped out. In guided Internet-delivered CBT, dropouts were more common with lower education and lower credibility/expectancy ratings. Higher adherence was associated with a larger reduction in health anxiety.

EXPERT OPINION

Unwanted effects are routinely seen in CBT for pathological health anxiety, but, under typical circumstances, appear to be acceptable in light of the treatment's efficacy. There is a need for more consistent methods to improve our understanding adverse events, dropouts, and overall symptom deterioration, and how these outcomes can be prevented.