Inverse relationship between 25 hydroxy Vitamin D and parathormone: Are there two inflection points?
Indian Journal of Endocrinology and Medicine Page : 422-427, DOI: 10.4103/ijem.IJEM_322_19
- Overview Hyperparathyroidism and vitamin D
- Patent to treat secondary hyperparathyroidism with 30 ng Vitamin D – March 2018
- Hypothyroidism risk reduced 32 percent in those getting vitamin D levels above 50 ng – Oct 2017
- Parathyroid Hormone levels increase 63 percent with age (33,000 people) – Sept 2017
- Hypothesis Vitamin D receptor controls PTH without needing Vitamin D – Aug 2015
- Need 40 ng of vitamin D to have proper PTH levels – May 2011
- ICU death rate reduced 3X when a single dose of vitamin D changed the PTH – Nov 2015
Pradip Mukhopadhyay1, Sujoy Ghosh1, Kingshuk Bhattacharjee2, Subhankar Chowdhury1
1 Department of Endocrinology, Institute of Post Graduate Medical Education and Research, Kolkata, West Bengal, India
2 Health Care Management, Senior Medical Scientific Liaison, Metabolics, Biocon Limited, Bengaluru, Karnataka, India
Context: There is no consensus about the inflection point for 25 hydroxy vitamin D below which the intact PTH level increases.
Objective: Determine the relationship/inflection point between 25 hydroxy vitamin D and parathormone levels.
Materials and Methods: We performed a population-based analysis on a nonobese cohort (n = 405).
Results: Prevalence of vitamin D deficiency was 58.76% (n = 228). Vitamin D insufficiency was found in 34.56% (n = 140). An inverse relationship between 25 hydroxy vitamin D (25(OH)D) and intact PTH exist, but strength of such relationship is weak (r = −0.16, P = 0.018). With respect to the 25(OH)D cut-off of 16 ng/mL by IOM (EAR linked), proportion of persons with high intact PTH was higher in the group with lower 25(OH)D compared with higher 25(OH)D group (P = 0.005) and it was similar for RDA linked cut-off of 20 ng/mL also (P = 0.017). LOWESS method revealed two inflection points at which PTH levels change. A less conspicuous inflection point was found at 32 ng/mL (95% CI, 27–36), which reasonably corroborates with the current cutoff of definition of vitamin D sufficiency, and the second, steeper inflection point was found at 16.5 ng/ml (95% CI, 14.9–18.8) which corroborates with the IOM supported EAR linked value of 25(OH)D level in general population and possible definition of vitamin D deficiency.
Conclusions: There are possibly two inflection points at which PTH levels change in relation to 25(OH)D levels