An online survey of exercise-related headaches among cyclists.

Background: Primary exertional headache (PEH) is a long-known phenomenon. Divergent prevalences of between 0.2 and 12.

The prevalence of sleep disorders in patients with Parkinson's disease. A self-reported, community-based survey.

Objective: Sleep disruption is common in patients with Parkinson's disease (PD). The goal of our survey was to gain insight into the causes of sleep disruption and into the prevalence of specific sleep disorders in PD.

Method: A sleep questionnaire was mailed to 400 unselected PD patients.