Methods
PD
Based on a stratified randomized cluster sampling, 1361 subjects ≥ 65 years in the community were recruited from Tainan City, Taiwan, from 2000 to 2001. PH was defined as a decrease in systolic/diastolic blood pressure of ≥ 20/10 mm Hg after 1 or 2 min of standing. PD was defined by a positive response to dizziness-like symptoms after standing up from a supine position. Functional status included the activities of daily living (ADLs) and instrumental activities of daily living (IADLs).