Doctoral thesis: vascular calcification may increase mortality in patients with chronic kidney disease

Jana Uhlinova showed in her doctoral thesis, which she defended at the UT Faculty of Medicine, that in chronic kidney disease, vascular calcification occurs most frequently in obese patients and with reduced kidney function. It is also associated with lower bone mineral density. This knowledge helps better assess the risk of disease-related complications and mortality.

Chronic kidney disease is a progressive and lifethreatening condition, in which kidney function gradually declines. As kidney function deteriorates, metabolic disturbances may develop, leading to the accumulation of calcium and phosphate in blood vessel walls – a process known as vascular calcification. This makes the vessels rigid, accelerates their premature ageing and increases the risk of cardiovascular diseases.

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Due to metabolic disturbances, bone density also decreases, and the risk of fractures rises. However, the relationship between vascular calcification and bone tissue density has been insufficiently studied to date.

In her thesis, Uhlinova examined the impact of adiposity, or obesity, as a risk factor for chronic kidney disease, since previous studies have noted the so-called obesity paradox, which suggests that obese patients with chronic kidney disease may live longer. The reasons for this contradiction are not entirely clear.

The doctoral researcher’s aim was, therefore, to determine how body composition and vascular calcification are related and how they influence the course of the disease in patients with chronic kidney disease. According to Uhlinova, a better understanding of these associations would support earlier diagnosis and timely intervention for vascular complications, thereby improving treatment outcomes.

During the study, the doctoral researcher analysed 168 patients with chronic kidney disease, evaluating their vascular calcification, bone density and other health indicators. She also compared the results of obese and non-obese patients.

Vascular calcification was found to be most extensive in obese patients with reduced kidney function. At the same time, the study did not confirm the previously described “adiposity paradox”: obesity was not associated with a more favourable course of the disease.

In addition, an inverse relationship was found between vascular calcification and bone density: the more calcifications were deposited in the blood vessels, the lower the patients’ bone mineral density. This association was evident for both the abdominal aorta and the peripheral blood vessels. The study also showed that vascular calcification, particularly in the abdominal aorta, is an important prognostic marker, as it increases the risk of cardiovascular complications and worsens the course of chronic kidney disease.

According to Uhlinova, the strength of the study lies in the combined use of several safe, simple and easily accessible methods, which can be used in routine clinical practice. The results confirm that vascular calcification is a serious complication of chronic kidney disease and that changes in bones and the cardiovascular system are closely interconnected. Therefore, in the treatment of chronic kidney disease, these aspects must be addressed in an integrated manner, and each patient must be given an individualised approach.

Jana Uhlinova defended her doctoral thesis, “Vascular calcification and its associations with obesity and bone mineral density in chronic kidney disease”, at the University of Tartu Faculty of Medicine. Her supervisors were Mai Rosenberg, Professor in Nephrology, and Margus Lember, Professor of Propaedeutics of Internal Medicine.