Using a patient-centred composite endpoint in a secondary analysis of the Control of Hypertension in Pregnancy Study (CHIPS) Trial

Abstract

Abstract Background Clinical trials commonly use multiple endpoints to measure the impact of an intervention. While this improves the comprehensiveness of outcomes, it can make trial results difficult to interpret. We examined the impact of integrating patient weights into a composite endpoint on the interpretation of Control of Hypertension in Pregnancy Study (CHIPS) Trial results. Methods Outcome weights were extracted from a previous patient preferences study in pregnancy hypertension (N = 183 women) which identified (i) seven outcomes most important to women (taking medication, severe hypertension, pre-eclampsia, blood transfusion, Caesarean, delivery 0.50 for each). ‘Tight’ control was superior when using subgroup (2) weights (95% CIs: 0.002, 0.07; p = 0.03), and ‘less-tight’ control was superior when using subgroup (3) weights (95% CIs: − 0.11, − 0.04; p < 0.01). Conclusions Evidence-based recommendations for ‘tight’ control are consistent with most women’s preferences, but for a sixth of women, ‘less-tight’ control is more preference consistent. Depending on patient preferences, a single trial may support different interventions. Future trials should specify component weights to improve interpretation. Trial registration ClinicalTrials.gov NCT01192412

Keywords

• Patient-centred
• Randomized controlled trial
• Composite endpoints
• Pregnancy hypertension
• Perinatal