Few studies have been conducted that explore the impact of cardiovascular disease (CVD) hospitalizations on patient adherence to CVD drugs. Medicaid beneficiaries at high-risk for CVD, a vulnerable population, had not been a focus of prior studies in exploring the impact of patient adherence to cardioprotective drugs on health utilization. The study population was Maryland Medicaid beneficiaries with hypertension, hyperlipidemia, or diabetes. Adherence rates to antidiabetic (AD), antihypertensive (AH), or antihyperlipidemic (AL) drugs were measured in the 6-month pre-index and post-index periods. Patients with and without CVD hospitalization were matched on gender, race, age (±5 years), and pre-index adherence rate (±5%). Adherence rate to cardioprotective drugs among patients with a CVD event was measured in the 6-month, one-year, or two-year post-index periods. Patients with and without adherence to cardioprotective drugs were matched using propensity score matching. Conditional logistic regression analysis was conducted to explore the impact of CVD hospitalization on patient adherence to AD, AH, or AL drugs. The association of patient adherence to cardioprotective drugs with hospital utilization was explored using Cox regression analysis. Patients with CVD hospitalization were more likely than those without CVD hospitalization to be adherent to AD or AH drugs in the 6-month post-index period. Improved adherence to AD, AH, or AL drugs comparing the 6-month post-index to the 6-month pre-index period was more likely to be shown in patients with CVD hospitalization than in those without CVD hospitalization. A substantial proportion of patients were not adherent to AD, AH, or AL drugs during the 6-month post-CVD hospitalization period. Patients who were adherent to at least one cardioprotective drug were less likely than those who were not adherent to be associated with the risk of experiencing any all-cause hospitalizations, CVD-related hospitalizations, or CVD-related emergency room (ER) visits. Hospital-based education might provide an opportunity for patients to improve their awareness of the importance of medication adherence. Follow-up interviews by health professionals could help patients maintain adherence to medication after hospital discharge. Medicaid beneficiaries at high-risk for CVD are vulnerable, and improving adherence to cardioprotective drugs in this population might contribute to a reduction in hospital utilization.