Activities of daily living among heart transplant candidates: Neuropsychological and cardiac function predictors

Background: The ability of patients to perform day-to-day tasks (e.g., medi cation management, dietary regulation) is an important concern of transplan t teams. Methods: We studied a clinical series of 75 heart transplant candidates and 38 controls to examine the predictive validity of demographic, neuropsycho logic, and cardiac function variables to a performance-based measure of ins trumental activities of daily living (IADL) capacity (i.e., Everyday Proble ms Test, EPT). Results: Multiple regression analyses, controlling for education and race, indicated that neuropsychologic tests accounted for between 34% and 67% of the variance across IADL domains (e.g., cooking, household chores, medicati on management). The IADL capacity was most consistently predicted by long-s tanding verbal ability (Shipley Institute of Living Scale-Vocabulary, SILS- VOC) and psychomotor speed and mental flexibility (Trail Making Test-Part B , TMT-B). Similarly, SILS-VOC and TMT-B also tended to show the best operat ing characteristics (i.e., sensitivity, specificity, positive predictive po wer, negative predictive power) for detection of dependence across IADL dom ains. In contrast, cardiac function measures (e.g., cardiac output, mean at rial pressure) were largely unrelated to the patient's performance on the p aper-and-pencil EPT task. Conclusions: Long-standing intellectual ability, and a measure of speeded i nformation processing and mental flexibility are the best predictors of IAD L capacity.