Ethical problems in pharmacogenetic studies of psychiatric disorders

The impact of advertising patient and public involvement on trial recruitment: embedded cluster randomised recruitment trial

BACKGROUND

Patient and public involvement in research (PPIR) may improve trial recruitment rates, but it is unclear how. Where trials use PPIR to improve design and conduct, many do not communicate this clearly to potential participants. Better communication of PPIR might encourage patient enrolment, as trials may be perceived as more socially valid, relevant and trustworthy. We aimed to evaluate the impact on recruitment of directly advertising PPIR to potential trial participants.

METHODS

This is a cluster trial, embedded within a host trial ('EQUIP') recruiting service users diagnosed with severe mental illness. The intervention was informed by a systematic review, a qualitative study, social comparison theory and a stakeholder workshop including service users and carers. Adopting Participatory Design approaches, we co-designed the recruitment intervention with PPIR partners using a leaflet to advertise the PPIR in EQUIP and sent potential participants invitations with the leaflet (intervention group) or not (control group). Primary outcome was the proportion of patients enrolled in EQUIP. Secondary outcomes included the proportions of patients who positively responded to the trial invitation.

RESULTS

Thirty-four community mental health teams were randomised and 8182 service users invited. For the primary outcome, 4% of patients in the PPIR group were enrolled versus 5.3% of the control group. The intervention was not effective for improving recruitment rates (adjusted OR = 0.75, 95% CI = 0.53 to 1.07, p = 0.113). For the secondary outcome of positive response, the intervention was not effective, with 7.3% of potential participants in the intervention group responding positively versus 7.9% of the control group (adjusted OR = 0.74, 95% CI = 0.53 to 1.04, p = 0.082). We did not find a positive impact of directly advertising PPIR on any other outcomes.

CONCLUSION

To our knowledge, this is the largest ever embedded trial to evaluate a recruitment or PPIR intervention. Advertising PPIR did not improve enrolment rates or any other outcome. It is possible that rather than advertising PPIR being the means to improve recruitment, PPIR may have an alternative impact on trials by making them more attractive, acceptable and patient-centred. We discuss potential reasons for our findings and implications for recruitment practice and research.

TRIAL REGISTRATION NUMBERS

ISRCTN, ISRCTN16488358 . Registered on 14 May 2014. Study Within A Trial, SWAT-26 . Registered on 21 January 2016.

Taking part in a pharmacogenetic clinical trial: assessment of trial participants understanding of information disclosed during the informed consent process

BACKGROUND

This study is the first to examine the understandings that participants have of the consent process in a pharmacogenetic trial of anti-depressant medication.

METHODS

This was a qualitative cross sectional study. There were 76 participants residing in London, Mannheim, Arhuus and Poznan.

RESULTS

Only one quarter of participants (none in Poznan) could articulate the concept of pharmacogenetics. Heritability and testing medication were also given as the purpose of the trial. Most participants had not appreciated harms that could derive from the trial. Even when shown the consent sheet, participants were confused about DNA profiling. There was evidence that participants appreciated weekly contact with researchers. Most said they would participate in a trial again but would like choice over the intervention they were assigned to.

CONCLUSION

Participants in this study showed a poor level of informed consent. Although this is not the first time this argument has been made, it is in the case of a pharmacogenetic trial. Further work should investigate the associations between extraneous factors such as information and social support on beneficial or untoward outcomes of antidepressant treatment.

Pharmacogenetic studies in depression: a proposal for methodologic guidelines

Pharmacogenetic studies in mood disorders are rapidly proliferating after the initial reports linking gene variants to treatment outcomes. However, a considerable range of methodologies has been used, making it difficult to compare results across studies and limiting the representativeness of findings. Specification of sampling source (inpatients vs outpatients, primary vs tertiary settings), standardization of diagnostic systems and treatments, adequate monitoring of compliance through plasma levels, sufficient length of observation (at least 6 weeks for acute antidepressant treatments, though 3-6 months are preferable), the use of a range of response criteria and the inclusion of possible environmental confounding variables (life events, social support, temperament) are all potentially important issues when planning pharmacogenetic studies. We reviewed the state-of-the-art methodology and suggested possible guideline for future studies.