Prescription and choice of diagnostic imaging by physician specialty in Alzheimer's Centers (Unitá di Valutazione Alzheimer - UVA) in Northern Italy

Background and aims: Physician's specialty has been shown to have an effect on health outcomes and financial expenditure in a number of conditions. This is particularly true in the differential diagnosis of cognitive deterioration, in which technological procedures are needed. The aim of this study is to assess the effect of physician specialty on the prescription of diagnostic imaging (CT and MR) in patients with cognitive impairment, referred to Alzheimer Evaluation Units (Unitá di Valutazione Alzheimer) in Northern Italy. Methods: An ad-hoc questionnaire was sent to UVA referents in northern Italy (Lombardy, Piedmont, Trentino, Emilia-Romagna and Veneto), requesting information on the frequency of prescriptions for CT and MR and reasons for the choice, on a 0 to 7 scale. Results: The physician-in-charge was a neurologist in 22 and a geriatrician in 22 Alzheimer's centers. Intensive use of CT was similar in neurologists and geriatricians (64 vs 68%), whereas intensive use of MR was more frequent in neurologists (41 vs 10%; p=0.03). Overall, organizational factors (availability of the scanner on-site and waiting list for imaging, mean weight=1.6±1.4) were as important as patient-related factors (age, severity of cognitive impairment, and clinical suspicion of cerebrovascular disease, mean weight 1.7±1.4; p=0.84). Sixty-five percent of neurologists based their choices between CT and MR on patient-related and 35% on organizational factors, whereas the opposite proportion was found for geriatricians (29 vs 71%, p=0.04). Conclusions: The high weight of organizational factors on the prescription of diagnostic imaging is not consistent with an evidence-based diagnostic system.