Stigma arises when social norms result in the marginalization of people with a certain identity or trait. Negative stereotypes of people in the stigmatized group result in their systematic exclusion and/or discrimination. Chronic disease diagnosis itself can lead to the development of disease-specific identity-based stigma, in that a person's identity is disrupted by a new label (e.g. "diabetic") applied to them, until they incorporate this new label into a positive sense of self. Minority stress theory describes the impact of identity-based marginalization on health outcomes. According to minority stress theory, discrimination and stigma may lead to heightened stress levels, which can translate over time into heightened mental and physical health disparities for the stigmatized group. Categories of stigma experienced by patients include enacted stigma, perceived stigma, self-stigma, and concealment. Enacted stigma refers to acts of discrimination against people in a stigmatized group. Perceived stigma refers both to the fear of experiencing enacted stigma, as well as to the shame resulting from belonging to or being associated with a stigmatized group. Self-stigma refers to the internalization of negative group stereotypes by members of the stigmatized group. Concealment, also called non-disclosure, refers to the hiding of a stigmatized identity or condition.