title: Apathy and depression in mild Alzheimer's disease: a cross-sectional study using diagnostic criteria.
abstract: Apathy and depression are the most frequent neuropsychiatric symptoms in Alzheimer's disease (AD). In a cross-sectional observational study of 734 subjects with probable mild AD, we evaluated the prevalence of apathy and depression. After the use of specific diagnostic criteria, we tested the interaction between the two syndromes and their relation with specific comorbidities, and different functional outcomes. Depression was diagnosed using the diagnostic criteria for depression in AD, and apathy with the diagnostic criteria for apathy in neuropsychiatric disorders. According to the specific diagnostic criteria, depression had a 47.9% prevalence, while apathy prevalence was 41.6%. Apathy and depression were associated in 32.4% of patients (n = 225). 9.4% (n = 65) had only apathy, 15.4% (n = 107) had only depression, and 42.9% had no apathy and no depression (n = 298). The three most frequent depressive symptoms were fatigue or loss of energy (59.4%), decreased positive affect or pleasure in response to social contacts and activities (46.2%), and psychomotor agitation or retardation (36.9%). Concerning apathy, loss of goal-directed cognition was the most frequently altered (63.6%), followed by loss of goal-directed action (60.6%) and loss of goal-directed emotion (43.8%). Patients with both apathy and depression more frequently required a resource allowance for dependency. Neurological comorbidities were more frequent in the "apathy and depression" and "depression alone" groups (p < 0.001). Apathy and depression overlap considerably, and this might be explained by the presence of some non-specific symptoms in both diagnostic criteria. The need for social support is higher when a patient fulfills the two diagnostic criteria.
authors.affiliation: Clinique de Psychiatrie et de Psychologie Médicale, Pole des Neurosciences Cliniques, CHU Nice, France. benoit.m@chu-nice.fr
authors.forename: Michel
authors.initials: M
authors.lastname: Benoit
authors.forename: Gilles
authors.initials: G
authors.lastname: Berrut
authors.forename: Johanna
authors.initials: J
authors.lastname: Doussaint
authors.forename: Serge
authors.initials: S
authors.lastname: Bakchine
authors.forename: Sylvie
authors.initials: S
authors.lastname: Bonin-Guillaume
authors.forename: Patrick
authors.initials: P
authors.lastname: Frémont
authors.forename: Thierry
authors.initials: T
authors.lastname: Gallarda
authors.forename: Pierre
authors.initials: P
authors.lastname: Krolak-Salmon
authors.forename: Thierry
authors.initials: T
authors.lastname: Marquet
authors.forename: Claude
authors.initials: C
authors.lastname: Mékiès
authors.forename: François
authors.initials: F
authors.lastname: Sellal
authors.forename: Stéphane
authors.initials: S
authors.lastname: Schuck
authors.forename: Renaud
authors.initials: R
authors.lastname: David
authors.forename: Philippe
authors.initials: P
authors.lastname: Robert
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D057565:Apathy; D010054:Brief Psychiatric Rating Scale; D003430:Cross-Sectional Studies; D003863:Depression / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D011897:Random Allocation; D012944:Social Support