Who goes next? Optimizing the allocation of adherence-improving interventions

Long-term adherence to medication is a critical factor in preventing chronic diseases, such as cardiovascular disease (CVD). To address poor adherence, physicians can recommend adherence-improving interventions; however, such interventions are costly and limited in availability. Knowing which patients will stop adhering helps to distribute available resources strategically. We developed a binary integer program (BIP) model to select patients for adherence-improving intervention under budget constraints. We further studied a long-term adherence prediction model using a dynamic logistic regression (DLR) model that uses patient claims data, medical health factors, demographics, and monitoring frequencies to predict the risk of future nonadherence. We trained and tested our predictive model on longitudinal data for cardiovascular disease in a large cohort of patients taking medication for cholesterol control seen in the national Veterans Affairs health system. Our study shows the importance of including past adherence to increase prediction accuracy. Finally, we assess the potential benefits of using the prediction model by proposing an algorithm that combines the DLR and BIP models to decrease the number of CVD events in a population.