Efficacy of Acceptance and Commitment Therapy in Daily Life (ACT-DL) in early psychosis: Results from the multi-center INTERACT randomized controlled trial

Importance Treatment in the early stages of psychosis is crucial to prevent poor clinical and social outcomes. Currently, no preventive interventions are available that reduce psychotic distress, or affective and negative symptoms as well as functioning, calling for more and dedicated treatments for these. Objective To investigate the efficacy of Acceptance and Commitment Therapy in Daily Life (ACT-DL), combining face-to-face therapy with an Ecological Momentary Intervention (EMI), in addition to treatment as usual for psychotic distress, in comparison to treatment as usual only. Design This single-blinded randomized clinical INTERACT trial investigated participants post-intervention and at 6 and 12-month follow-up. Participants were recruited between June 1, 2015 and December 31, 2018. Assessors were blinded to treatment allocation. Setting INTERACT is a multi-center trial recruiting participants from secondary mental health services in 5 regions in Belgium and The Netherlands. Participants The sample was a referral sample of individuals aged 15-65 years with a clinically established UHR or FEP status. Interventions Individuals were randomly assigned (1:1) to ACT-DL, consisting of 8 ACT sessions augmented with an EMI app in addition to treatment as usual, or to treatment as usual only. Main outcomes and measures The primary outcome was a reduction in psychotic distress as assessed with CAARMS at post-intervention, 6-and 12-month follow-up. Secondary outcomes included symptom severity (measured with BPRS and BNNS), functioning (measured with SOFAS and SFS) and momentary psychotic distress (measured with the Experience Sampling Method, a structured diary technique). All analyses were described in the trial protocol and in a postregistration on the open-science framework, prior to accessing the data. Results Of the 196 individuals assessed for eligibility, 148 were randomized to ACT-DL+TAU (n=71) or TAU (n=77) (72 female (49%), average age 25 (SD = 6), 71 FEP (48%)). 115 (78%) provided primary outcome data at least at one follow-up assessment. There was no evidence of a greater reduction in CAARMS distress in ACT-DL+TAU compared to TAU (χ 2 (3)=2.38; p=.50). However, general psychopathology (χ 2 (3)=14.44; p=.002); affective (χ 2 (3)=8.55; p=.04) and negative symptom severity (χ 2 (3)=19.96; p<.001) as measured with the BPRS was reduced, as well as negative symptoms as assessed with BNNS (χ 2 (3)=15.96; p=.001) in. Furthermore, global functioning improved (χ 2 (3)=8.72; p=.033) in ACT-DL+TAU compared to TAU, whereas social functioning failed to reach significance (χ 2 (3)=7.41; p=.060). Finally, a clear and significant reduction was found in momentary psychotic distress (χ 2 (3)=21.56; p<0.001), whereas no effects were found for momentary psychotic experiences (χ 2 (3)=1.02; p=.599), momentary positive (χ 2 (3)=4.17; p=.124) or negative (χ 2 (3)=2.78; p=.249) affect. No serious adverse events directly related to the therapy occurred. Conclusions and relevance INTERACT did not support a significant effect on psychotic distress as assessed with the CAARMS. However, significant improvements were found for momentary psychotic distress, global functioning and negative symptomatology. These results are promising given that these latter problems are among the hardest to treat. Trial Registration Dutch Trial Register: NTR4252 Key Points Question Can Acceptance and Commitment Therapy (ACT) in Daily Life, a combined face-to-face ACT intervention with a digital daily life Ecological Momentary Intervention, reduce psychotic distress in the early stages of psychosis? Findings This randomized clinical trial of 148 individuals in the early stages of psychosis (UHR or FEP) found no evidence that ACT-DL improved psychotic distress at post-intervention, 6 or 12-month follow-up over and above treatment as usual. However, significant effects were found for momentary psychotic distress, negative symptoms and functioning. Meaning Whereas the blended care approach of face-to-face ACT with the ACT-DL EMI did not improve psychotic distress over and above treatment as usual, it provided a promising avenue for the treatment of momentary psychotic distress as well as for negative symptoms and improving functioning, some of the hardest to treat problems in individuals with UHR and FEP.