Occurrence of depression and anxiety prior to Parkinson's disease

Objective To assess the relationship between depression and anxiety and Parkinson s disease (PD) Background Many people with PD suffer from depression and anxiety prior to the onset of motor symptoms Studies suggest these psychiatric conditions may be risk factors for PD or prodromal non-motor symptoms Methods Using a population-based approach in three California counties we recruited 371 incident PD cases 402 population and 115 sibling controls We recorded self-reports of lifetime depression/anxiety diagnoses and use of psychotropic medications We adjusted for age race sex pack-years of smoking and education and also conducted analyses after excluding (lagging) both diagnoses and medication use first occurring within 2 5 10 and 20 years of the index/diagnosis date Results Cases were more likely to have received a diagnosis of depression or anxiety at any time prior to Index date (OR 1 42 95% CI 1 01 2 00) but were not more likely to have been both diagnosed and treated (OR 111 95% CI 077 1 60) Male PD patients received diagnoses combined with treatment more often than population controls within 5 years of PD diagnosis (OR 2 21 95% CI 1 21 404 2 year lag OR 244 95% CI 1 29 461 5 year lag OR 1 67 95% CI 080 3 49) We did not see any differences for females Results for cases compared to sibling controls were similar to those for population controls Conclusion These results suggest that depression and anxiety may be early symptoms during the prodromal phase of PD (C) 2010 Elsevier Ltd All rights reserved