Five-year outcomes of the STOP-AD randomised controlled trial: Long-term effects of early emollient therapy in high-risk infants.

Early-life skin barrier enhancement has been proposed as a strategy to prevent atopic dermatitis (AD), but results from emollient prevention trials have been inconsistent, and long-term outcomes remain poorly defined. The STOP-AD trial previously demonstrated a reduction in AD incidence following brief early emollient use in high-risk infants. Whether these effects persist beyond infancy is unknown.

This study reports the blinded five-year follow-up of the STOP-AD single-centre, randomised controlled trial. Term infants at high risk of AD were randomised within 4 days of birth to either twice-daily whole-body emollient application for the first 8 weeks of life or to standard routine skin care. At 5 years, participants underwent blinded, in-person clinical assessment. AD was diagnosed using UK Working Party Diagnostic Criteria, and disease severity was assessed using SCORAD. Primary outcome was point prevalence of AD at 5 years. Secondary outcomes included AD severity. Complete-case analyses were supplemented by multiple imputation to assess the impact of missing data.

A total of 177 children completed the five-year follow-up. The point prevalence of AD at 5 years was lower in the intervention group than in the control group (12.3% vs. 24.0%; RR 0.52, 95% CI 0.26-1.02; p = .048). Among children with AD, disease severity was also lower in the intervention group (median SCORAD 12.0 [IQR 8.2-15.2] vs. 19.6 [IQR 11.8-23.4]; p = .034). Multiple imputation to account for missing outcome data produced a similar treatment effect (OR 0.45, 95% CI 0.19-1.03; p = .060), although with greater uncertainty.

Early, short-term emollient use initiated in the neonatal period was associated with lower AD prevalence and severity at 5 years in high-risk children. Although the effect estimate remained similar following multiple imputation, uncertainty due to attrition remained. These findings suggest that brief early-life barrier support may influence longer-term AD outcomes and support further investigation of the timing and formulation of preventive skin-barrier interventions.