PS07 Ethnic disparities in diagnosis, clinical outcomes and treatment response in delusional infestation: a retrospective observational analysis from a psychodermatology service in East London

Abstract

Delusional infestation (DI), although rare, carries a significant healthcare burden and remains a challenge to treat. Similarly to psoriasis and schizophrenia, ethnic disparities in DI may also exist. This retrospective observational study aimed to identify disparities in diagnosis, clinical outcomes and treatment response in DI using routinely collected data from the Barts Health NHS Foundation Trust psychodermatology service. Data were collected on demographics, broad ethnic group, date of symptom onset, referral and diagnosis, baseline and 12-month post-­treatment Clinical Global Impression-Severity (CGI-S) scores, antipsychotic treatment and past medical history. Overall, 194 patients were included: 74% identified as ethnically White and 26% as Black. The majority of patients presented after the fourth decade of life, and both White and Black cohorts demonstrated a female predilection. White patients had a higher burden of comorbidities (65%) than Black patients (29%). Recreational drug use was more prevalent in the former group, and a greater proportion of White patients had a history of mental health conditions (47%) compared with Black patients (33%). In contrast, Black patients experienced longer delays, waiting on average 11.6 months from symptom onset to referral to a DI service, with a further 14-month delay from referral to initiation of antipsychotic therapy. Baseline CGI-S scores were comparable between White and Black patients. Despite similar baseline severity, Black patients remained on antipsychotic therapy for longer (White: 5.63 months, Black: 9.00 months), were more likely to receive several antipsychotic medications (White: 4%, Black: 9%) and were less responsive to treatment (mean CGI-S change: White: −1.05, Black −0.73). Fewer Black patients were lost to follow-up than White patients (45% vs. 62%). Further research should explore the causes of these differences and consider mitigation strategies such as implementation of clear referral pathways, patient education, culturally competent assessments and timely access to psychodermatology services.