APOE and Mental deterioration: Overall, cognitive (e.g., Mini-Mental State Examination [MMSE] [29]) and clinical (e.g., clinical examination and discussions) tests were used in nearly all patients (>95%), with blood tests (i.e., genetic tests for APOE ɛ4 or other relevant mutations, or blood tests to rule out treatable causes of cognitive decline such as vitamin B12 deficiency) being used in half (50.2%) (Table 2).