1. An implantable system configured to be implanted in a patient, comprising: an accelerometer; a neural stimulator configured to deliver neural stimulation to a neural target; and a controller configured to use the accelerometer to detect laryngeal vibration, and configured to deliver a programmed neural stimulation therapy using the neural stimulator and using detected laryngeal vibration as an input to the programmed neural stimulation therapy, wherein the neural stimulator is configured to deliver the neural stimulation at a neural stimulation frequency, the system further comprising a bandpass filter configured to filter an accelerometer signal to the neural stimulation frequency to detect laryngeal vibration modulated at the neural stimulation frequency, and wherein the controller is configured to use the accelerometer to detect cough, to deliver the neural stimulation with a programmed duty cycle including a stimulation ON portion and a stimulation OFF portion, to monitor an accelerometer signal for a cough during the ON portion, and to titrate the neural stimulation therapy if the cough occurs during the ON portion of the neural stimulation therapy.