In short, the reason is that Medicaid reimbursement rates for providers is too low. Saurabh Jha, however, explains the point a bit more artistically in his Health Care Blog piece.
Medicaid pays a cardiologist, with years of training, $25-40 for a consultation to manage a complex patient with multiple comorbidities, on polypharmacy, where the cardiologist must indulge in shared decision making and also ensure the patient adheres to statins. For comparison, my personal trainer charges me $80. There’s no shared decision making – he tells me to do “burpees” and I must abide or face his wrath.
Note that although Medicaid patients do face challenges to timely access to physicians, particularly in certain regions or for certain specialties, a majority of physicians do accept Medicaid. The Kaiser Family Foundation found that:
About 70% of office-based physicians accept new Medicaid patients, compared to about 85% who accept new patients with private insurance or Medicare.
This finding does vary across specialty. For instance, psychiatrists are especially likely to not accept Medicaid patients.