title: Cognitive performance in nondemented nonpsychotic Parkinson disease patients with or without a history of depression prior to the onset of motor symptoms.
abstract: In Parkinson disease (PD), cognitive impairment is common, occurs mainly in the form of milder deficits (as opposed to dementia), and commonly coincides with depression. In this cross-sectional study, we evaluated whether depression that existed before the onset of typical motor symptoms (pre-PD depression) reflected on the actual cognitive performance. Nondemented nonpsychotic PD patients with (test, n = 27) and without (control, n = 112) a history of pre-PD depression, caliper-matched for age, education, and disease duration were assessed for motor and nonmotor disease characteristics and in a battery of cognitive tests. Test patients had higher actual depression/anxiety levels. Gradual multivariate and mediation analysis indicated unfavorable effects of pre-PD depression on cognition: a direct effect on mental set shifting/response inhibition (independent of actual depression/ anxiety or other factors); and indirect effects on other cognitive domains mediated through the increased depression/anxiety. Data suggest that pre-PD depression favors poorer cognitive abilities in nondemented patients at a given time after PD has been diagnosed.
authors.affiliation: Department of Neurology, University Hospital Centre Zagreb, Zagreb University School of Medicine, Zagreb, Croatia.
authors.forename: Natasa
authors.initials: N
authors.lastname: Klepac
authors.forename: Sanja
authors.initials: S
authors.lastname: Hajnsek
authors.forename: Vladimir
authors.initials: V
authors.lastname: Trkulja
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001007:Anxiety / Q000150:complications / Q000523:psychology; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology; D003430:Cross-Sectional Studies; D003704:Dementia / Q000523:psychology; D003863:Depression / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance; D012720:Severity of Illness Index; D013997:Time Factors