1. A method comprising: receiving, at a computing device, body parameter data of a patient; determining that the patient is in a particular sleep cycle stage based on the body parameter data and at least one of: detection of a sleep stage transition; an amount of time the patient spends in one or more stages during the particular sleep cycle; an amount of time the patient spends in one or more stages during a sleep period that includes multiple sleep cycles; and a combination thereof; detecting, while the patient is in the particular preselected sleep cycle stage, a seizure event; and adjusting, at the computing device, a cranial nerve stimulation parameter.