To the Editor: The article by Dr Ross and colleagues1 was widely reported to show that coffee is an independent
"protective factor" against the development of Parkinson disease (PD). Using
a prospective longitudinal epidemiological database, the authors did, in fact,
find an inverse association between higher caffeine intake and risk of developing
PD. However, association does not prove causation. They did not consider another
potential explanation of this association; namely, that incipient or preclinical
PD causes decreased novelty-seeking behaviors.2,3
Several studies have shown inverse associations between tobacco, alcohol,
and coffee intake and PD,1- 3
and it is more plausible that these various substances (including other caffeinated
beverages such as tea, cola, and chocolate) are underused by persons with
incipient PD, rather than that each agent independently protects against PD.
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Purchase Online Access to this article for 24 hours
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 2
Customize your page view by dragging & repositioning the boxes below.
More Listings atJAMACareerCenter.com >
and access these and other features:
Enter your username and email address. We'll send you a link to reset your password.
Enter your username and email address. We'll send instructions on how to reset your password to the email address we have on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.