Hyperparathyroidism is a disease that predominantly affects the female population. A new study conducted by a group of Italian researchers demonstrates the relationship between mild primary hyperparathyroidism and increased cardiovascular risk.
We discuss this with Dr. Stella Bernardi, a researcher in Endocrinology at the Department of Medical Sciences, University of Trieste (Italy), who coordinated the study with colleagues from Cattinara Hospital in Trieste and the University of Padua.
Dr. Bernardi, please explain what hyperparathyroidism is.
“Hyperparathyroidism is a pathology characterized by an abnormal secretion of a hormone called parathormone. This condition is generally related to an adenoma, which is a benign nodule on one of the four parathyroid glands that are located behind the thyroid gland.
The hyperparathyroidism has as its first targets the bones and kidneys, weakening the first through a process of demineralization, which increases the calcium in the blood circulation and in the urine with consequent risk of kidney stones. In severe forms of the disease, the calcium in the blood increases significantly, causing further disturbances to the osteomuscular system of the gastrointestinal tract to the neurological system. In these cases, the action required is the removal of the parathyroid.
There are various forms of hyperparathyroidism; our study focused on mild primary hyperparathyroidism, which affects up to 11% of the female population of menopausal age. This form is not associated with marked increases in calcium, so the patient has no major complaints, but there’s still an increased risk of both osteoporosis and kidney stones.”
What did you find with your study?
“The patients with mild primary hyperparathyroidism also have an increased cardiovascular risk, so it’s important to treat this disease.
The premise behind this study is that although it was known that parathormone had effects on both blood vessels and the heart, effects that are well demonstrated in severe forms of hyperparathyroidism, the relationship between mild primary hyperparathyroidism and cardiovascular risk was unclear. Therefore, we wondered whether mild primary hyperparathyroidism was also associated with alterations in the cardiovascular system.
To answer that question, we performed a meta-analysis study published in The Journal of Clinical Endocrinology & Metabolism and picked up by Physician’s Weekly.”
Please explain more about what a meta-analysis study is.
“A meta-analysis study is a statistical methodology that is used to solve a problem whose results are conflicting. Through meta-analysis you analyze all the existing data and allow a synthesis of it in order to reach a conclusion. In our specific case, through meta-analysis we’ve shown that parathormone, even in forms of mild primary hyperparathyroidism, leads to stiffening of the vessels which is a cardiovascular risk factor. In addition, we also found a significant correlation between parathyroid removal and reduced arterial stiffness (which underlies cardiovascular damage).
I’d like to point out that ours is the first study to use meta-analysis to make a connection between mild primary hyperparathyroidism and arterial stiffness. The important thing is that mild primary hyperparathyroidism is the most common form of hyperparathyroidism and therefore the cardiovascular consequences can affect a significant number of people, especially postmenopausal women (see here for more on cardiovascular disease in women).”
What future developments do you see for this research?
“It will be necessary to confirm this data on an expanded population with randomized trials, so that we can confirm our observations and statistical analysis. Above all, it will be necessary to establish thresholds, for example, to operate on a patient who shows an increase in urinary calcium, there’s a well-defined threshold to which we refer. Similarly, for bones we have a reference value of demineralization, beyond which the patient has the parathyroid removed. To date, there is no reference value of arterial stiffness to be able to determine when it’s necessary to operate on the patient with mild primary hyperparathyroidism.
Another important aspect to which we hope to contribute with further studies is to verify what impact mild primary hyperparathyroidism (and parathyroidectomy) may have on patients with increased cardiovascular risks, such as diabetics.
All of this I believe will lead to a change in guidelines that don’t currently include cardiovascular risk assessments in patients with mild primary hyperparathyroidism.”
One last question: is it fair to call this approach an example of personalized medicine?
“Exactly. Establishing the exact correlation between mild primary hyperparathyroidism and existing diseases, and also based on other characteristics such as gender, family history and age, will lead us to establish the best treatment for the individual patient.”
This post is also available in: Italiano