OTHR-01. USING COGNITION TO PREDICT RISK OF MEDICAL DECISION-MAKING IMPAIRMENT IN BRAIN CANCER

BACKGROUND: Medical decision-making capacity refers to the ability to make informed decisions about medical treatment. Understanding is the most cognitively demanding aspect of medical decision-making and requires the ability to comprehend medically-related information and then use that information to make decisions about diagnosis, prognosis, and treatment options. In previous papers, we have shown that knowledge about specific cognitive abilities that affect understanding in brain cancer could be used to construct actuarial equations designed to help clinicians identify persons with brain cancer or brain metastases at risk of understanding impairment. METHODS: In total, 184 participants (67 with brain metastasis, 41 with non-brain metastasis, 29 with malignant glioma, and 47 healthy controls) were recruited. All participants were administered a neuropsychological battery that included a performance-based measure of medical decision-making capacity. Impairment cutoffs were calculated from control group performance. Using the cognitive scores that were most highly associated with understanding, logistic and linear regression models were used to construct actuarial equations designed to predict intact/impaired understanding and understanding scores, respectively. RESULTS: As expected, both brain cancer groups had poorer understanding than controls and approximately 50% of both brain cancer groups exhibited impaired understanding. Over 24% of the non-brain metastasis group exhibited impaired understanding. Significant associations were found between understanding and all administered cognitive variables, with the strongest correlations noted as between understanding and measures of executive function, verbal memory, and verbal fluency. Using these cognitive variables, we were able to construct predictive equations that showed strong psychometric properties. CONCLUSIONS: These data demonstrate how cognitive measures can estimate medical understanding in persons with cancer. Clinically, these findings suggest that poor verbal memory, executive function, and/or phonemic fluency function could serve as “red flags” for reduced consent capacity in this patient population, and thus signal that a more comprehensive medical decision-making capacity evaluation is warranted.