Deprescribing is an essential component of safe prescribing, especially for people with higher levels of polypharmacy. Identifying individuals prepared to consider medicine changes may facilitate deprescribing-orientated reviews. We aimed to explore the relationship between revised patient attitudes towards deprescribing (rPATD) scores and medication changes in older people prescribed ≥15 medicines. A secondary analysis of rPATD scores and prescription data from a cluster randomised controlled trial of a GP-delivered, deprescribing-orientated medication review was conducted. The association between number of medicines stopped, started and changed and baseline rPATD scores was assessed using Poisson regression adjusting for patient age, gender, study group allocation, baseline number of medicines and effects of clustering. Participants (n=404) had a mean age of 76.4 years and were prescribed a mean of 17.1 medicines at baseline. Willingness to stop a medicine was associated with higher rates of both deprescribing (IRR: 1.40; 95%CI: 1.06-1.84) and initiating medicines (IRR: 1.43; 95%CI: 1.09-1.88). Satisfaction with current medicines was associated with a lower rate of deprescribing (IRR: 0.69; 95%CI: 0.57-0.85). The rPATD questionnaire could be used as part of a deprescribing intervention to identify participants who may be prepared to engage in deprescribing, enabling more efficient use of clinician time during complex consultations.