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Introduction Previous cohort studies have identified a relationship between depression and subsequent Parkinson’s disease (PD). 1 However, none to date have focused on whether specific psychopathology increases this risk. We hypothesised that in individuals with depression, presence of psychomotor retardation (identified through natural language processing (NLP)), would be associated with a greater risk of subsequent PD.Methods The South London and Maudsley Clinical Record Interactive Search (CRIS) system was used to identify patients retrospectively from electronic health care record data (02/01/2007 – 31/03/2023). Inclusion criteria were a primary or secondary diagnosis of unipolar depression at age >40. Participants were excluded if they had baseline PD.Descriptive data were extracted and primary analysis included Cox proportional hazards regression analysis, adjusting for sex, ethnicity, antipsychotic use, neurological comorbidities, and psychiatric comorbidities. Secondary analyses included a linear mixed effects model as per the approach described by Singh-Manoux et al.2 to investigate the trajectory of psychomotor retardation in relation to PD diagnosis. Statistical analyses were performed in R.Results Of all patients with depression, 2402 (1362 female, mean age at diagnosis = 56.92) had a positive hit on the NLP app for psychomotor retardation, and 3925 (2166 female, mean age at diagnosis = 57.88) had a negative hit for psychomotor retardation or a positive hit for psychomotor agitation. Cox proportional hazard ratio for development of PD was 1.43 (95% CI 1.01 – 2.01, p = 0.04). Sensitivity analyses (Lexis expansion for year-at-risk adjustment, excluding cases with a first psychomotor event within one year of censor date) supported the results of the primary analysis.When running the linear mixed effects model with a quadratic time interaction, it was observed that there was a significant negative interaction between time as a linear variable, and Parkinson’s status (p = 0.03).Discussion These findings indicate that in individuals with depression, presence of psychomotor retardation is associated with increased risk of subsequent PD diagnosis. Graphical modelling of the risk trajectory suggests that this risk dates back to at least 10 years prior to PD diagnosis.References Gustafsson H, Nordström A, Nordström P. Depression and subsequent risk of parkinson disease: a nationwide cohort study. Neurology 2015;84(24):2422-9.Singh-Manoux A, Dugravot A, Fournier A, Abell J, Ebmeier K, Kivimäki M, Sabia S. Trajectories of depressive symptoms before diagnosis of dementia: a 28-year follow-up study. JAMA Psychiatry 2017;74:712–8.San H, Lewington S. Lexis expansion-age-at-risk adjustment for survival analysis. Brussels: Statistics and Pharmacokinetics Pharmaceutical Users Software Exchange conference. 2013. SP09.