When cognitive evaluation does not disclose a neurologic disorder: experience of a university behavioral neurology clinic.

Objective: We examined clinical features, referral patterns, and diagnostic outcome of patients receiving cognitive evaluation in a behavioral neurology clinic who had no neurologic disorder.
Background: Cognitive complaints may indicate Alzheimer Disease (AD) or many other conditions. Accurate early evaluation of these complaints is critical, and appropriate subspecialty clinic referral has public health policy implications.
Method: This retrospective medical records review included 342 consecutive patients seen at the Neurobehavior Clinic of the University of Colorado Hospital from July 2006 through June 2008. All patients received an initial diagnosis by a clinic attending and subsequent consensus diagnosis by 3 subspecialists board certified in Behavioral Neurology & Neuropsychiatry.
Results: Among the 342 patients, 68% had a neurologic disorder, the most common of which was probable AD (17%). The remainder had nonneurologic diagnoses: 20% had a psychiatric diagnosis, 7% had no neuropsychiatric disorder, and 5% had a medical diagnosis. Of those with nonneurologic diagnoses, 65% were referred by primary care providers, and the most common symptom was memory loss (72%). In the psychiatric subgroup, depression was the most frequent diagnosis (56%). All normal individuals had concern about cognitive decline. In the medical subgroup, medication effect was the most frequent diagnosis (50%).
Conclusions: Probable AD was the most common neurologic diagnosis, but 32% of the referred patients had no neurologic disorder, and most of these individuals had a psychiatric cause for cognitive complaints. These results highlight the need for policies promoting more effective use of subspecialty clinics dedicated to neurologic disorders of cognition.