Using Machine Learning to Predict Medication Therapy Problems among Patients with Chronic Kidney Disease

INTRODUCTION: Patients with chronic kidney disease (CKD) are at risk of medication therapy problems (MTPs) due to high comorbidity and medication burden. Using data from the Kidney Coordinated HeAlth Management Partnership (Kidney CHAMP) trial, we used machine learning to build a predictive model to identify MTP high-risk patients with CKD in the primary care setting. METHODS: We used baseline data from patients enrolled in the intervention arm of the Kidney CHAMP trial, completed May 2019-July 2022, which tested a population health management strategy, including medication management, for improving CKD care. The dataset was divided into 80% training and 20% testing subsets. The area under the ROC curve (AUROC) was used to assess classification accuracy in distinguishing between patients with and without MTP. Eight candidate models were considered, and the top three performing models (random forest, support vector machines, and gradient boosting), based on cross-validated AUROC on training data, underwent further refinement. The model with the highest AUROC in the testing set, while considering the bias/variance trade-off, was selected as the best-performing model. SHapley Additive exPlanations was then leveraged using the best-performing model to evaluate the impact of each predictor to the final risk score. RESULTS: Among 730 patients who received medication review at baseline, 566 (77.5%) had at least 1 MTP. Key demographics were mean age 74 years, 55% female, 92% white, 64% with diabetes, and the mean number of medications 5.8 at baseline. The random forest model had the best performance on the testing set with AUROC 0.72, sensitivity 0.80, and specificity 0.64. The five most influential variables, ranked in descending order of importance for predicting individuals with MTP, were diabetes status (yes/no), hemoglobin A1C (HbA1C), urine albumin-to-creatinine ratio (UACR), systolic blood pressure, and age. CONCLUSION: In outpatient primary care, a machine learning-based MTP risk calculator that uses routinely available clinical data can identify patients with moderate-high-risk CKD who are at high risk for developing MTPs.