Comorbidity

The simultaneous presence of two or more medical conditions or disorders in the same individual. Comorbidity is extremely common in neurodevelopmental and mental health conditions—for example, ADHD frequently co-occurs with anxiety, depression, autism, learning disabilities, and substance use disorders. In accessibility, comorbidity means that users often have overlapping and sometimes conflicting accessibility needs, making it important to design flexible interfaces that can accommodate multiple conditions simultaneously rather than optimizing for a single disability type.