Research article

Age-related increases in parathyroid hormone may be antecedent to both osteoporosis and dementia

Eric R Braverman^1,8 , Thomas JH Chen² , Amanda LC Chen³ , Vanessa Arcuri⁴ , Mallory M Kerner⁴ , Anish Bajaj⁴ , Javier Carbajal⁴ , Dasha Braverman⁴ , B William Downs⁵ and Kenneth Blum^4,5,6,7

¹Department of Neurological Surgery, Weill Cornell College of Medicine, New York, New York, USA

²Department of Health and Occupational Safetly, Chang Jung Christian University, Taiwan, Republic Of China

³Department of Engineering, Chang Jung Christian University, Taiwan, Republic Of China

⁴Department of Neurological Research, Path Research Foundation, New York, NY, USA

⁵Department of Molecular Nutrition & Nutrigenomics, LifeGen, Inc La Jolla, California, USA

⁶Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston -Salem, NC, USA

⁷Department of Psychiatry, School of Medicine, University of Florida, Gainesville, FL, USA

⁸Path Medical Research Foundation, 304 Park Ave South, 6th Floor, NY, NY 10010, USA

author email corresponding author email

BMC Endocrine Disorders 2009, 9:21doi:10.1186/1472-6823-9-21

Published:	13 October 2009

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 ≤ 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).

Conclusion

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.