BACKGROUND: Effect of fish oil supplementation in parkinsonian patients with depression measured by Montgomery-Asberg Rating Scale (MADRS), the Clinical Global Impressions Scale (CGI) and Beck Depression Inventory (BECK).

METHOD: Double-blind, placebo-controlled study analyzed depression in 31 patients with Parkinson's Disease and Major Depression (DSM-IV). The patients were double-blind separated in 2 groups that received fish oil (containing omega-3 fatty acids) or mineral oil capsules for 3 months; each group was separated in 2 new groups: one taking antidepressant medication
and another one not taking it.

RESULTS: 29 patients completed the 12-week trial, 58% were female and the mean age was 64.4 years old. Patients supplemented with fish oil showed a significant decrease in MADRS and CGI-Depression scores, and there was no difference among groups in BDI. 14 patients (42%) met criteria for >/=50% reduction in MADRS score, 7 patients (22%) met criteria for remission (final MADRS total score
CONCLUSION: These results reveal that
PD patients taking fish oil, with or without antidepressants, presented improvement in depressive symptoms and indicate that the intake of omega-3 can be used with an antidepressant effect or as adjuvant therapy with some other medication. This is a first pilot study with parkinsonian patients and omega-3 supplementation and requires replication in a larger sample.