Efficacy of Internet-Delivered Prevention for Anxiety and Depression Onset

Overview

This randomized controlled trial evaluated an internet-based, transdiagnostic cognitive-behavioral intervention to prevent onset of anxiety and depressive disorders in adults with subthreshold symptoms. Both individually guided and automatically guided digital interventions significantly reduced the incidence of anxiety and depressive disorders over 12 months compared to a waitlist control.

Background

Anxiety and depressive disorders are common and impose significant personal and societal burdens. Preventive strategies are critical to reduce their prevalence, and internet- and mobile-based interventions (IMIs) offer scalable, accessible options. Most prevention programs target anxiety or depression separately, despite their high comorbidity, limiting public health impact. Transdiagnostic, self-tailored IMIs may better address shared mechanisms and individual needs, potentially improving prevention outcomes.

Data Highlights

Key Findings

• Both individually guided and automatically guided internet-based interventions significantly reduced the 12-month incidence of anxiety and depressive disorders compared to waitlist control.
• The cumulative incidence of disorder onset was 23.1% in IG-IMI and 20.7% in AG-IMI versus 36.0% in WLC.
• Hazard ratios indicated a 41% risk reduction with IG-IMI (HR=0.59) and a 53% risk reduction with AG-IMI (HR=0.47) relative to control.
• Number needed to treat was 7.76 for IG-IMI and 5.79 for AG-IMI, indicating clinical relevance.
• Participants completed on average 6.84 sessions in IG-IMI and 6.19 sessions in AG-IMI, demonstrating good adherence.
• The study population was predominantly female, Caucasian, average age 40, with 81.8% presenting both subclinical anxiety and depressive symptoms.

Clinical Implications

Internet-delivered, transdiagnostic cognitive-behavioral interventions can effectively prevent the onset of anxiety and depressive disorders in adults with subthreshold symptoms. Automated guidance offers a resource-efficient alternative to individual guidance without compromising efficacy, supporting scalable preventive mental health strategies. Clinicians should consider incorporating such digital interventions to reach at-risk populations and reduce disorder incidence.

Conclusion

This trial demonstrates that both individually and automatically guided internet-based interventions significantly reduce the risk of developing anxiety and depressive disorders over one year. These findings support the use of scalable, transdiagnostic digital prevention programs in clinical practice.

References

1. Efficacy of Internet-Delivered Targeted Prevention for Onset of Anxiety and Depression: A Three-Arm Randomized Controlled Trial