Some disorders may be very limited in their functional effects, while others may involve substantial disability and support needs. The degree of ability or disability may vary over time and across different life domains. Furthermore, continued disability has been linked to institutionalization, discrimination and social exclusion as well as to the inherent effects of disorders. Alternatively, functioning may be affected by the stress of having to hide a condition in work or school etc., by adverse effects of medications or other substances, or by mismatches between illness-related variations and demands for regularity.