title: Age-related increases in parathyroid hormone may be antecedent to both osteoporosis and dementia.
abstract: BACKGROUND
  Numerous studies have reported that age-induced increased parathyroid hormone plasma levels are associated with cognitive decline and dementia. Little is known about the correlation that may exist between neurological processing speed, cognition and bone density in cases of hyperparathyroidism. Thus, we decided to determine if parathyroid hormone levels correlate to processing speed and/or bone density.
  
  
  METHODS
  The recruited subjects that met the inclusion criteria (n = 92, age-matched, age 18-90 years, mean = 58.85, SD = 15.47) were evaluated for plasma parathyroid hormone levels and these levels were statistically correlated with event-related P300 potentials. Groups were compared for age, bone density and P300 latency. One-tailed tests were used to ascertain the statistical significance of the correlations. The study groups were categorized and analyzed for differences of parathyroid hormone levels: parathyroid hormone levels <30 (n = 30, mean = 22.7 +/- 5.6 SD) and PTH levels >30 (n = 62, mean = 62.4 +/- 28.3 SD, p <or= 02).
  
  
  RESULTS
  Patients with parathyroid hormone levels <30 showed statistically significantly less P300 latency (P300 = 332.7 +/- 4.8 SE) relative to those with parathyroid hormone levels >30, which demonstrated greater P300 latency (P300 = 345.7 +/- 3.6 SE, p = .02). Participants with parathyroid hormone values <30 (n = 26) were found to have statistically significantly higher bone density (M = -1.25 +/- .31 SE) than those with parathyroid hormone values >30 (n = 48, M = -1.85 +/- .19 SE, p = .04).
  
  
  CONCLUSIONS
  Our findings of a statistically lower bone density and prolonged P300 in patients with high parathyroid hormone levels may suggest that increased parathyroid hormone levels coupled with prolonged P300 latency may become putative biological markers of both dementia and osteoporosis and warrant intensive investigation.
authors.affiliation: Department of Neurological Research, Path Research Foundation, New York, NY, USA. pathmedical@aol.com
authors.forename: Eric R
authors.initials: ER
authors.lastname: Braverman
authors.forename: Thomas J H
authors.initials: TJ
authors.lastname: Chen
authors.forename: Amanda L C
authors.initials: AL
authors.lastname: Chen
authors.forename: Vanessa
authors.initials: V
authors.lastname: Arcuri
authors.forename: Mallory M
authors.initials: MM
authors.lastname: Kerner
authors.forename: Anish
authors.initials: A
authors.lastname: Bajaj
authors.forename: Javier
authors.initials: J
authors.lastname: Carbajal
authors.forename: Dasha
authors.initials: D
authors.lastname: Braverman
authors.forename: B William
authors.initials: BW
authors.lastname: Downs
authors.forename: Kenneth
authors.initials: K
authors.lastname: Blum