title: Serum parathyroid hormone predicts time to fall independent of vitamin D status in a frail elderly population.
abstract: Very frail older people constitute an increasing proportion of ageing populations and often have vitamin D deficiency. Falls are frequent in this population and have usually been associated with vitamin D deficiency. In this prospective study we measured serum 25-hydroxyvitamin D (25OHD), serum PTH, and falls in 637 ambulatory subjects living in institutional aged care facilities (intermediate-care hostels or nursing homes). The study sample comprised 121 men (mean age, 82.1 yr) and 516 women (mean age, 86.7 yr). Two hundred and seventy-four subjects fell one or more times over a mean duration of follow-up of 10.2 months. Vitamin D deficiency, defined as a serum 25OHD level below 39 nmol/liter was present in 73.6%. Baseline serum 25OHD and PTH were significantly associated with falls in univariate analyses. In multivariate analyses that also corrected for balance and health status, PTH remained a significant predictor of falls independent of 25OHD. Serum PTH is a predictor of time to first fall in the frail elderly independent of vitamin D status and measures of general health.
authors.affiliation: Institute of Bone and Joint Research, Department of Public Health, ANZAC Research Institute, University of Sydney, Prince of Wales Medical Research Institute, Sydney, New South Wales 2065, Australia. sambrook@med.usyd.edu.au
authors.forename: P N
authors.initials: PN
authors.lastname: Sambrook
authors.forename: J S
authors.initials: JS
authors.lastname: Chen
authors.forename: L M
authors.initials: LM
authors.lastname: March
authors.forename: I D
authors.initials: ID
authors.lastname: Cameron
authors.forename: R G
authors.initials: RG
authors.lastname: Cumming
authors.forename: S R
authors.initials: SR
authors.lastname: Lord
authors.forename: J
authors.initials: J
authors.lastname: Zochling
authors.forename: Y Y
authors.initials: YY
authors.lastname: Sitoh
authors.forename: T C
authors.initials: TC
authors.lastname: Lau
authors.forename: J
authors.initials: J
authors.lastname: Schwarz
authors.forename: M J
authors.initials: MJ
authors.lastname: Seibel
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D016330:Frail Elderly; D006801:Humans; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D013997:Time Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000150:complications
chemical_list: D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D