Depression in Parkinson's Disease: Real‐World Prescribing Patterns and Treatment Dynamics from a Nationwide Greek Cohort

BACKGROUND: Depression in Parkinson's disease (PD-DD) is common, but little is known for outcomes after antidepressants are started. OBJECTIVES: We examine prescribing patterns and treatment trajectories for depression in Parkinson's disease (PD) in a Greek nationwide cohort (IDYKA) of 28,370 PD-DD patients and 660,504 DD patients without PD. METHODS: Target trial emulation with propensity score weighting comparing SSRIs, non-SSRI antidepressants, atypical antipsychotics (AAPs), and benzodiazepines on discontinuation and switching/augmentation. RESULTS: The PD-DD association (pooled OR 8.37, 95% CI 5.02-13.98) is age-dependent in both sexes. Clinicians favored sedative agents, particularly mirtazapine (age- and gender-adjusted OR [aOR] 1.26, 95% CI 1.22-1.30), duloxetine (1.41, 1.36-1.48), and quetiapine (1.33, 1.28-1.38). AAP were less commonly discontinued compared to SSRIs (HR 0.838 [0.771, 0.911]). Non-SSRI ADs were associated with higher switch/augmentation rates (1.155 [1.058, 1.240]). CONCLUSIONS: In PD depression, AAP outlast SSRIs in real-world persistence and non-SSRIs are more commonly switched or augmented.