title: Prospective study of phobic anxiety and risk of Parkinson's disease.
abstract: Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, Massachusetts 02115, USA. mweissko@hsph.harvard.edu
authors.forename: Marc G
authors.initials: MG
authors.lastname: Weisskopf
authors.forename: Honglei
authors.initials: H
authors.lastname: Chen
authors.forename: Michael A
authors.initials: MA
authors.lastname: Schwarzschild
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
authors.forename: Alberto
authors.initials: A
authors.lastname: Ascherio
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006282:Health Personnel / Q000706:statistics & numerical data; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000453:epidemiology* / Q000209:etiology*; D010698:Phobic Disorders / Q000150:complications*; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology