Trial participation may offer benefits beyond medication for autistic adults, study finds
Autistic adults could be supported to start and continue taking an antidepressant or placebo medication within the context of a randomised controlled trial (RCT), according to new research supported by the NIHR Biomedical Research Centre: Bristol. Participants in both the treatment and placebo groups of the STRATA study discussed improvements in their anxiety, suggesting that trial participation could offer its own therapeutic effects.
To better understand how autistic adults would respond to being part of a RCT, researchers embedded a smaller qualitative study within the larger STRATA RCT. STRATA (Sertraline for anxiety in adults with a diagnosis of autism) was a study aimed at finding out whether the medication sertraline is an effective treatment for anxiety in adults with a diagnosis of autism.
The smaller embedded study looked at the experiences of 62 autistic adults who were blinded to whether they were taking sertraline or a placebo. Researchers found that many participants reported feeling calmer, happier and better able to manage their anxiety over the course of the study.
Crucially, these positive changes were described equally by those taking the active medication and those taking placebo. This suggests that factors beyond the pharmacological effects of antidepressants may play an important role in improving mental health outcomes for autistic adults.
Participants attributed their experiences to a range of influences, including expectations about treatment, developing new coping strategies, and reflecting on their mental health during the trial. Many were also comfortable with the possibility that improvements could be linked to a placebo effect, reframing this as a sign of personal progress.
The study highlights how the wider context of clinical trials (including regular contact with supportive researchers and opportunities for self-reflection) may itself provide therapeutic benefits. Frequent appointments, flexible dosing, and clear communication were all identified as helping participants feel safe and supported to continue.
Although some participants reported side effects, these were similar in type and frequency across both treatment groups, and often manageable. While a small number discontinued medication as a result, most continued with support from the trial team.
Importantly, the findings challenge assumptions that autistic people may be reluctant to take part in RCTs due to uncertainty around treatment allocation. Instead, participants were generally accepting of blinding and randomisation.
Study authors conclude that both clinical practice and trial design could benefit from these insights. Approaches such as starting medication at low doses, respecting communication preferences, offering shared decision-making, and providing regular follow-up may improve treatment experiences and adherence.
Dr Alba X Realpe, Research Fellow at Bristol Medical School and joint first author, said:
“Our findings show that taking part in a clinical trial that adapts around neurodivergence-needs can itself be beneficial for autistic adults. The relationships, support and structure built into the study appear to play a key role in improving wellbeing, regardless of the medication received.”
The study adds to growing evidence that non-pharmacological factors (including therapeutic relationships and patient expectations) can influence mental health outcomes. Researchers say future trials should consider these elements carefully to enhance both participant experience and study outcomes.
