Introduction: Information about calcium-phosphorus metabolism (CPM) and bone turnover in patients with liver cirrhosis (LC), as well as clarifying their diagnostic value for assessing bone structure disorder, will help doctors to detect their lesions in timely manner and, based on the information received, to choose well-founded comprehensive treatment strategy.
Aim: To characterize the indicators of calcium-phosphorus metabolism and bone turnover in patients with liver cirrhosis, and to find out their diagnostic value for detecting bone structure disorder.
Materials and methods: In randomized manner 90 patients with LC (27 women and 63 men of age from 18 to 66), who were treated at the Lviv Regional Hepatological Center (Communal Non-Commercial Enterprise of Lviv Regional Council “Lviv Regional Clinical Hospital”) between 2016 and 2020, were included in the research. The research was carried out in two stages. The purpose of the first stage was to obtain information that would allow characterizing indicators of CPM (total calcium, ionized calcium, phosphorus, total vitamin D (25-hydroxyvitamin D), and parathyroid hormone) and bone turnover (osteocalcin, P1NP, alkaline phosphatase (bone formation markers), and β-Cross Laps (bone resorption marker)) in patients with LC, and the purpose of the second stage was to find out their diagnostic value for assessing bone structure disorder of them. To perform research, an experimental group (EG) (72 patients with impaired bone mineral density (BMD)), which was divided into EG A (46 patients with osteopenia) and EG B (26 patients with osteoporosis), and a comparison group (18 patients with normal BMD) were formed. The control group consisted of 20 relatively healthy people.
Results: At the first stage, it was established that the frequency of cases of increased alkaline phosphatase content was statistically significantly different in LC patients with osteopenia and osteoporosis (p = 0.002), as well as with osteoporosis and normal BMD (p = 0.049). Impaired BMD in general had significant direct stochastic relationship with vitamin D deficiency, decrease in osteocalcin content and increase in P1NP content in serum (Yule's Coefficient of Association (YCA)) >0.50); osteopenia – with decrease in phosphorus content, vitamin D deficiency and increase in P1NP content (YCA >0.50); and osteoporosis – with vitamin D deficiency, decrease in osteocalcin content, increase in P1NP content, and increase in alkaline phosphatase content in serum (YCA >0.50). Significant inverse stochastic relationship was recorded between vitamin D insufficiency and each of the impaired BMD manifestations (YCA <-0.50), which most likely indicates that it is characteristic of normal BMD. At the second stage, it was found that among indicators of CPM and bone turnover, only increase in alkaline phosphatase content in serum can be diagnostically valuable marker of osteoporosis in patients with LC (р <0.050; YCA >0.50; coefficient contingency = 0.32), which has medium sensitive (80.77 %) and positive predictive value (70.00 %) for it. Although other indicators of CPM and bone turover did not confirm their diagnostic value in our research, they may be useful for monitoring pathogenetic changes in bone structure disorder and evaluating the effectiveness of their treatment in patients with LC.
Conclusion: Indicators of calcium-phosphorus metabolism and bone turnover, which are characteristic of bone structure disorder and its absence in patients with liver cirrhosis, were revealed. Among them, an increase in alkaline phosphatase content in serum, which is a moderately sensitive marker of osteoporosis, is diagnostically valuable.