Creating a Global Research Database That Connects Genetic Information and Long-term Health Data to Improve Personalized Treatment for People With Serious Mental Illness

Inclusion Criteria: \- All participants must have an electronic health record in a primary or secondary care service. Mental Health cohort(s) • Have received a diagnosis and/or treatment/referral for mental illness for MDD, BD, Schizophrenia. • Having an available electronic health record • Current age 18+ (no upper age limit) • Can speak English Dementia cohort • Participants aged 18+ (no upper age limit) • Currently alive and are, or have been, old age psychiatry patients • Received relevant diagnosis or referral: EITHER • Clinical diagnosis of dementia, mild cognitive impairment (MCI) or subjective cognitive impairment (SCI) OR • Memory clinic referral • Must be willing and able to complete a validated cognitive assessment (MoCA or SLUMS). All dementia patients will undergo the extended biomarker analysis. Exclusion Criteria: \- Mental Health cohort(s) • Patients without capacity to provide consent. Dementia cohort • Inability to understand spoken and/or written spoken English • Individuals with intellectual disability. • Patients with dementia in Creutzfeldt-Jakob disease (CJD), Huntington's, HIV dementia, alcohol-related dementia, intellectual disability, traumatic brain injury at any time. • Patients diagnosed with depression (only an exclusion criterion for MCI/SCI patients), psychosis, bipolar disorder prior in the pre-index period - to be checked at screening.