December 2010
Drijgers RL, Dujardin K,
Reijnders JS, Defebvre L, Leentjens AF
Background: Apathy is a
common neuropsychiatric syndrome in Parkinson's Disease (PD) that
affects quality of life. Research into apathy has been hampered by a
lack of broadly accepted diagnostic criteria. Recently, diagnostic
criteria for apathy in neuropsychiatric disorders have been proposed,
which to date have not been validated in PD.
Aim: To validate the proposed diagnostic criteria for apathy in PD.
Design and methods: In
a cross-sectional study, outpatients with PD visiting a movement
disorders clinic underwent a protocolized assessment of motor function,
activities of daily living (ADL), cognition and mood. In addition, the
diagnostic criteria for apathy were administered as well as two apathy
rating instruments: the Lille Apathy Rating Scale (LARS) and the apathy
section of the Neuropsychiatric Inventory (NPI).
Results: Of
the included patients 17.2% were diagnosed with apathy according to the
criteria. Acceptability and internal consistency of the criteria was
good, as was the concurrent validity with the LARS and apathy section of
the NPI. Discriminant validity of the criteria with depression was
moderate to good. All domains of criterion B (behavior, cognition,
emotion) contributed to the diagnosis of apathy, of which reduced
goal-directed behavior was the most frequently observed symptom.
Conclusion: The
recently proposed diagnostic criteria for apathy are useful in clinical
practice and in research with PD patients with and without cognitive
impairment.
