Features of Bone Metabolism in Workers Exposed to Harmful Production Factors

Aim. To study the characteristics of bone metabolism in workers engaged in vibration-hazardous occupations. Design. Observational, comparative, and cross-sectional study. Materials and methods. A total of 152 miners exposed to constant or periodic occupational vibration exceeding the permissible exposure levels by 3–11 dB were examined. The first main group included 75 workers — excavator operators and heavy truck drivers — diagnosed with vibration disease (VD) caused by whole-body vibration. Among them, 47 (62.7%) individuals had VD stage I, and 28 (37.3%) had stage II. The mean age was 55.4 ± 0.46 years (range: 32–61), and the average work experience was 22.6 ± 6.7 years (range: 9–28). The second main group comprised 77 workers — including drift miners, drill rig operators, and borehole drillers — also diagnosed with VD, resulting from combined exposure to local and whole-body vibration. Stage I VD was detected in 47 (61%) workers, and stage II in 30 (39%). The mean age in this group was 56.4 ± 2.3 years (range: 33–60), with an average work experience of 20.8 ± 6.2 years (range: 5–25). The control group consisted of 24 men comparable in age (mean age 46.1 ± 5.7 years) to the main groups. These individuals had no occupational exposure to vibration and resided in the same region as the miners. Clinical and laboratory parameters, bone metabolism markers, and bone mineral density (BMD) were assessed using ultrasound densitometry. Results. In miners, a direct correlation was found between serum calcium levels and the T-score (r = 0.62, p < 0.05), indicating a negative calcium balance contributing to decreased BMD. There was a moderate inverse correlation between work experience and the concentration of bone-specific alkaline phosphatase (BALP) (r = –0.34; p = 0.042), as well as between work experience and osteocalcin (OC) levels (r = –0.41; p = 0.029). A moderate direct correlation was found between work experience and the serum levels of β-CrossLaps (r = 0.58; p = 0.012), and cathepsin K (r = 0.64; p = 0.002). As BMD decreased, BALP and OC concentrations also significantly decreased (p < 0.05), while cathepsin K and β-CrossLaps levels increased significantly (p < 0.001). Conclusion. Occupational vibration, especially when combined with physical overexertion, contributes to disturbances in calcium-phosphorus balance and bone metabolism, manifesting as a decrease in bone formation markers and an increase in bone resorption markers. The slowdown of osteogenesis and activation of bone resorption in miners increases the risk of metabolic osteopathies. Among workers exposed to both local and whole-body vibration, decreased levels of bone formation markers (BALP and OC) and elevated concentrations of bone resorption markers (β-CrossLaps and cathepsin K) were observed. Ultrasound densitometry revealed a high prevalence of osteopenic syndrome. A correlation was established between bone metabolism markers and work experience. These findings highlight the importance of early laboratory diagnosis and ongoing monitoring of osteopenic syndrome in miners, especially those with long-term exposure to occupational vibration and extensive work history. Keywords: miners, occupational vibration, reduced bone mineral density, bone metabolism, osteopenic syndrome.