1. A system for vagus nerve stimulation of a patient, the system comprising: an accelerometer configured to provide patient motion signals; an input assembly adapted to receive the patient motion signals, the input assembly including an acceleration-based disease state estimator configured to primarily use the patient motion signals to generate a disease state estimate of the patient, the input assembly further adapted to process the patient motion signals to generate one or more control input signals; an output assembly adapted to receive the one or more control input signals from the input assembly and generate a neuromodulation signal based at least in part on a comparison of the disease state estimate and a reference input corresponding to a target disease state; and an electrode configured to deliver the neuromodulation signal to the patient's vagus nerve.