Vitamin D Status and Its Association with Parathyroid Hormone Concentration in Brazilians
It is evident from several studies that not all patients with hypovitaminosis D develop secondary hyperparathyroidism. What this means for bone biochemistry and. Furthermore, square root transformations were performed on serum PTH, and natural log transformations were performed on vitamin D intake. relationship between 25(OH)D levels and concomitant parathyroid hormone levels. METHODS: Reference Intakes for vitamin D and calcium by the Institute.
This is how it all happens: PTH starts pulling calcium from your bones and into your blood. So you stop absorbing too much calcium and allows your body to lower its blood calcium. When you get enough vitamin D from good sun exposure and supplementation habits and enough calcium from your diet, this allows you to maintain a healthy calcium level in your blood and keep good amounts of calcium in your bones.
Healthy vitamin D and calcium habits also help keep your PTH levels in check. While getting too little vitamin D will cause PTH to be too high and lead to poor bone health, getting too much can also be bad for your health.
When your body gets too much vitamin D, it absorbs too much calcium and makes your calcium levels in the blood too high.
This is called hypercalcemia. Sometimes PTH can be too high or too low in certain conditions that affect the parathyroid, making getting the right amount of vitamin D really important. These conditions are called hyperparathyroidism and hypoparathyroidism. Hyperparathyroidism Hyperparathyroidism is excessive secretion of PTH, or over-activity of parathyroid glands.Calcium and Phosphate Metabolism
There are two main types of hyperparathyroidism: Because of the adenoma, the parathyroid can make too much PTH, which can cause calcium to be too high in the blood, and overtime, lead to poor bone health. If you have primary hyperparathyrodism, you need to work with your doctor to see if you can take vitamin D.
PTH & Vit D Physiology
Secondary hyperparathyroidism Secondary hyperparathyroidism is caused by either long term vitamin D deficiency or kidney failure. Introduction Vitamin D plays a key role in serum calcium homeostasis, acting as a hormone in autocrine and paracrine manners [ 1 ]. The main function of 1,25 OH 2D3, which is the active form of vitamin D, is to increase calcium absorption from the intestine, through interaction with vitamin D receptor VDRexpressed in the distal as well as in the proximal intestine [ 2 ].
While absorbing solar energies ultraviolet B7-dehydrocholesterol provitamin D3 converts to vitamin D3 cholecalciferol. Vitamin D can also be taken by diet, from fortified dairy products and fish oils [ 34 ]. Vitamin D3 enters the circulation and is transported to the liver, where it is converted to hydroxyvitamin D 25 OH Da form thought to be biologically inactive, but which is widely regarded as the best indicator of vitamin D status.
Studies over the last decade have shown that the effects of vitamin D are not limited to the maintenance of calcium homeostasis. Vitamin D deficiency can be caused by nutritional factors, decreased solar exposure, malabsorption resulting from intestinal inflammation, celiac disease or gastric surgery, prolonged use of anticonvulsants and corticoids, and others [ 6 ]. Low 25 OH D status leads to reduced efficiency in intestinal calcium absorption, and the body reacts by increasing the secretion of parathyroid hormone PTH [ 7 ].
Especially in elderly people, increased serum PTH concentration can cause bone turnover and bone loss, defects in mineralization, and increased risk of fractures [ 8 ]. Furthermore, vitamin D supplementation with calcidiol, in addition to improving serum 25OHD, also significantly lowers PTH levels, reducing secondary hyperparathyroidism [ 9 ].
Does vitamin D affect calcium levels and the parathyroid glands?
According to the existing literature, vitamin D deficiency not only affects bone metabolism and quality, but also seems to be related to autoimmune diseases, neurological diseases, and cancer [ 10 ].
Studies performed in different populations have shown that vitamin D deficiency is not restricted to northern countries where sunlight exposure is restricted, but could also be common in subtropical countries [ 11 ].
There is still no agreement on which levels of vitamin D should be considered normal or abnormal, and there are also differences in the methodologies used by laboratories to measure circulating vitamin D levels. However, there is an agreement that plasma levels of 25 OHO D are the best indicator for vitamin D evaluation [ 12 ]. Low concentrations of serum 25 OH D are suggested to be associated with high levels of parathyroid hormone PTH and a higher risk of mortality [ 15 ].
Materials and Methods The present study is a descriptive cross-sectional study of data obtained through a databank from a clinical laboratory in Belo Horizonte, MG, Brazil. A total of 25 OH D tests results were collected between and Tests results from PTH measurements were also collected and analyzed.
PTH & Vit D Physiology - Basic Science - Orthobullets
Samples were collected with a minimum eight hours fasting and vitamin D levels were obtained by quantitative determination of 25 OH D using automated competitive chemiluminescence immunoassay method Diasorin Liaison.
The reference values used in the present study were those determined by the clinical laboratory as follows: Data were expressed as mean, standard deviation, median, and percentiles. Statistical analysis was performed using Mann—Whitney and Spearman nonparametric test. Access to the clinical laboratory databank was previously authorized and the collected data were confidential. No personal information was obtained. The study was submitted and approved by the ethics committee from Universidade Fumec, protocol number Results A total of laboratory test results were analyzed for 25 OH D levels.
It was possible to observe that the amount of serum 25 OH D tests performed by the clinical analysis laboratory increased during the period of this study. In the first year, tests were performed, compared to in the last year of the study data not shown.
Data analysis also detected a value of The results were similar for each year analysis Table 1. Results for serum 25 OH D levels observed by analysis of a clinical laboratory databank.
Statistical analysis of 25 OH D values according to individuals age demonstrated that a negative correlation could be found between age and 25 OH D values. It was possible to note that The data suggest that vitamin D deficiency tends to increase with ageing. Percentage of vitamin D deficiency according to age group. Numbers in parenthesis show the exact percentage for each age group.
Parathyroid Glands: Vitamin D and calcium levels
A significant correlation was found between age and vitamin D deficiency. Analysis of 25 OH D measurements showed that Percentage of serum 25 OH D results according to reference values. These data suggest that individuals with vitamin D deficiency show high PTH values No significant differences were observed regarding the season when vitamin D was measured or the gender of the individuals.