Systems and methods are provided for using stored physiologic information about a subject to detect a previous treatment event. Physiologic information can be sensed from a subject using one or more sensors. Using a detection circuit, a change in the sensed physiologic information, such as a change from reference physiologic information, can be used to identify a candidate previous treatment event. An alert or other information about the candidate treatment event can be provided to a patient or clinician. In an example, a candidate treatment event can include a heart failure or diuresis treatment that is identified using information about a change in one or more of a subject's circadian pattern, a subject's thoracic impedance, or a subject's respiration status.
