Better quality of life in patients offered financial incentives for taking anti-psychotic medication: Linked to improved adherence or more money?

Abstract

In a randomised controlled trial, patients were offered financial incentives to improve their adherence to anti-psychotic maintenance medication. Compared to a control group without the incentives, they had an improved adherence and also better subjective quality of life (SQOL) after 1year. This paper explores the question as to whether this improvement in SQOL was associated with the amount of money received or with the improved adherence itself. A secondary analysis was performed using data of the experimental group in the trial. Adherence was assessed as the percentage of all prescribed long-acting anti-psychotic injections that were taken by the patient. In regression models, we tested whether changes in medication adherence and/or the amount of incentives received over the 12-month period was associated with SQOL, as rated on the DIALOG scale. Adherence changed from 68.49% at baseline to 88.23% (mean difference in adherence=19.59%, SD=17.52%). The total amount of incentives received within the 1-year study period varied between £75 and £735, depending on the treatment cycle and the number of long-acting injections taken. Improvement in adherence was found to be a significant predictor of better subjective quality of life (β=0.014, 95% CI 0.003-0.025, p=0.014), whilst the amount of incentives received was not (β=0.0002, 95% CI -0.002 to 0.002, p=0.818). Improved medication adherence is associated with a more favourable SQOL. This underlines the clinical relevance of improved adherence in response to financial incentives in this patient group.